2 Forthcoming Events 3 FUTUROTEXTIEL 08 International Journal of Space Structures 4 Transparent inflatable globe and giant lightweight mirrors, Belgium Amphitheatre OLIMAR, Uruguay 5 Visiting the Bigo, Italy 6 Membrane structures in India 8 Designing, detailing and building with textiles. Projects realised with different fabric. 13 Rhino-Membrane 14 Integrated design of tensile structures 16 Open Learning Centre, Belgium Dalian Seals Show Hall, China 18 Canopies for Hospital, Canada 19 Muncipal Sport Pavilion, Spain 20 Techtextil 10 th Student Competition 2009 N EWSLETTER OF THE E UROPEAN BASED N ETWORK FOR THE D ESIGN AND R EALISATION OF T ENSILE S TRUCTURES www.tensinet.com N EWSLETTER N R . 15 - OCTOBER 2008 - PUBLISHED TWICE A YEAR Dear Tensinet members, We would like to kindly invite you to the next TensiNet Meetings on Monday the 10 th November 2008 in Stuttgart. The morning lectures will present research results and new projects. In the afternoon during the Annual General Meeting it will be possible to comment on the current activities of the TensiNet Association. The Partner Meeting will start at 3pm. During the Partner meeting a new Board will be elected. LOCATION University of Stuttgart, Pfaffenwaldring 27, Lesesaal EXTRA VISIT 1 During the TensiNet Meeting day you are kindly invited to visit Labor Blum. 2 Guided visit to New Architecture in Stuttgart Sunday the 9 th November 2008 or subsequently to the meetings like e.g. the new Mercedes- Museum, the new modern arts gallery and the new exposition halls. Interested? Send a mail to heidrun. [email protected]before 27 th October. Extra information will be sent. CONFIRMATION Confirmation of attendance for the morning lectures, the annual general meeting & partner meeting is obligatory. Send an e-mail before the 27 th October to [email protected]and a CC to [email protected]. PROGRAM 9:30 - 12:00 PRESENTATION 1 - Prof. Dr.-Ing. K.-U. Bletzinger New developments for the analysis of membrane structures. Stress singularities which are arising from the theoretically based cutting patterns will be analysed. 2 - Labor Blum New materials and their importance for the environmental performance by simulation and measurement will be presented. 3 - Dr.-Ing. D. Ballhause The failure of uni-axially and bi-axially stressed materials analysed on the basis of the Weibull assumptions of probability for the fracture of multi- filament yarns. Extracted results of his thesis will be shown. 4 - Schlaich-Bergermann and Partner Actual projects will be presented. 12:00 - 13:30 LUNCH BREAK 13:30 - 15:00 ANNUAL GENERAL MEETING & WORKING GROUPS 15:00 - 17:00 PARTNER MEETING Partner Meeting Annual General Meeting Monday 10 th November 2008 - STUTTGART TensiNet is becoming stronger: the ‘team’ supporting the Association is consolidating and the dissemination and networking activities are increasing. The whole group working in the field of tensile surface structures is growing. Since the beginning of August Evi Corne has been working part-time for the TensiNet Association. We were able to finalise this issue before the Annual General Meeting (10 th of November in Stuttgart) thanks to her help! We had a meeting with the graphic designers T.M.&C. (Talent, Marketing & Communication) and from 2009 we will change the ‘style’ to improve the readability of the newsletter and include larger photos. On the website www.tensinet.com, under Tensinet News, events and contract proposals are announced. TensiNet is supporting the Techtextil Student Competition 2009 and an invitation to participate has been sent to our ‘school’ members. TensiNet is present at the Futurotextiel08 Fair (from 9 October until 7 December, Kortrijk) with a continuous slide show displaying recent projects and in the exhibition with samples of the used materials. The Special Issue No. 4 of Vol. 23 (last of this year) of the International Journal of Space Structures will be entitled ‘Tensioned membrane construction’. Papers in this Special Edition were selected from those presented at the TensiNet Symposium ‘Ephemeral Architecture: Time and Textiles’ held at the Politecnico di Milano, in 16-18 April 2007. The Working Groups Website&Database, Analysis&Materials and Specifications have started up or continue their activities. We kindly invite all TensiNet members to participate in the next Annual General Meeting to be held on the 10 th of November, in Stuttgart. We hope to meet you in Stuttgart. Marijke Mollaert Heidrun Bögner-Balz EDITORIAL
Transcript
2
Forthcoming Events
3
FUTUROTEXTIEL 08
International Journal of Space
Structures
4
Transparent inflatable globe
and giant lightweight mirrors,
Belgium
Amphitheatre OLIMAR, Uruguay
5
Visiting the Bigo, Italy
6
Membrane structures in India
8
Designing, detailing and
building with textiles.
Projects realised
with different fabric.
13
Rhino-Membrane
14
Integrated design
of tensile structures
16
Open Learning Centre, Belgium
Dalian Seals Show Hall, China
18
Canopies for Hospital, Canada
19
Muncipal Sport Pavilion, Spain
20
Techtextil
10th Student Competition 2009
N E W S L E T T E R O F T H E E U R O P E A N B A S E D N E T W O R K F O R T H E D E S I G N A N D R E A L I S AT I O N O F T E N S I L E S T R U C T U R E S
w w w . t e n s i n e t . c o m N E W S L E T T E R N R . 1 5 - O C T O B E R 2 0 0 8 - P U B L I S H E D T W I C E A Y E A R
Dear Tensinet members,We would like to kindly invite you to the next TensiNetMeetings on Monday the 10th November 2008 inStuttgart. The morning lectures will present researchresults and new projects. In the afternoon during theAnnual General Meeting it will be possible to commenton the current activities of the TensiNet Association. The Partner Meeting will start at 3pm. During the Partnermeeting a new Board will be elected.
LOCATION University of Stuttgart, Pfaffenwaldring 27, Lesesaal
EXTRA VISIT1 During the TensiNet Meeting day you are kindly
invited to visit Labor Blum. 2 Guided visit to New Architecture in Stuttgart
Sunday the 9th November 2008 or subsequently to the meetings like e.g. the new Mercedes-Museum, the new modern arts gallery and thenew exposition halls.
Interested? Send a mail to heidrun. [email protected] 27th October. Extra information will be sent.
CONFIRMATIONConfirmation of attendance for the morninglectures, the annual general meeting & partnermeeting is obligatory. Send an e-mail before the 27th October to [email protected] and a CC to [email protected].
PROGRAM9:30 - 12:00 PRESENTATION
1 - Prof. Dr.-Ing. K.-U. BletzingerNew developments for the analysis of membranestructures. Stress singularities which are arising from thetheoretically based cutting patterns will be analysed.
2 - Labor BlumNew materials and their importance for theenvironmental performance by simulation andmeasurement will be presented.
3 - Dr.-Ing. D. BallhauseThe failure of uni-axially and bi-axiallystressed materials analysed on thebasis of the Weibull assumptions ofprobability for the fracture of multi-filament yarns. Extracted results of histhesis will be shown.
4 - Schlaich-Bergermann and PartnerActual projects will be presented.
12:00 - 13:30 LUNCH BREAK13:30 - 15:00 ANNUAL GENERAL MEETING
& WORKING GROUPS
15:00 - 17:00 PARTNER MEETING
Partner MeetingAnnual General Meeting
Monday 10th November 2008 - STUTTGART
TensiNet is becoming stronger: the ‘team’ supporting the Association is consolidating and the dissemination andnetworking activities are increasing. The whole group working in the field of tensile surface structures is growing.Since the beginning of August Evi Corne has been working part-time for the TensiNet Association. We were able to finalise this issue before the Annual General Meeting (10th of November in Stuttgart) thanks to her help!We had a meeting with the graphic designers T.M.&C. (Talent, Marketing & Communication) and from 2009 we will change the ‘style’ to improve the readability of the newsletter and include larger photos.
On the website www.tensinet.com, under Tensinet News, events and contract proposals are announced. TensiNet issupporting the Techtextil Student Competition 2009 and an invitation to participate has been sent to our ‘school’ members. TensiNet is present at the Futurotextiel08 Fair (from 9 October until 7 December, Kortrijk) with a continuous slide showdisplaying recent projects and in the exhibition with samples of the used materials. The Special Issue No. 4 of Vol. 23 (last of this year) of the International Journal of Space Structures will be entitled‘Tensioned membrane construction’. Papers in this Special Edition were selected from those presented at the TensiNetSymposium ‘Ephemeral Architecture: Time and Textiles’ held at the Politecnico di Milano, in 16-18 April 2007. The Working Groups Website&Database, Analysis&Materials and Specifications have started up or continue theiractivities.We kindly invite all TensiNet members to participate in the next Annual General Meeting to be held on the 10th ofNovember, in Stuttgart. We hope to meet you in Stuttgart.
Marijke MollaertHeidrun Bögner-Balz
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Editorial Board Mike Barnes, John Chilton, Evi Corne, Niels De Temmerman, Brian Forster, Peter Gosling, Marc Malinowsky, Marijke Mollaert, Peter Pätzold, Rudi Scheuermann, Javier Tejera.
Structural Membranes 2009 International ConferenceStuttgart, Germany
05 > 07/10/2009
www.congress.cimne.upc.es/membranes09
The “Simposio Latinoamericano de Tenso-Estructuras” (Latin American Symposium on Tensile Structures) was first celebrated at theSchool of Architecture and Urbanism of TheUniversity of Sao Paulo, Brazil in 2003, and it wassuccessfully received by professionals, students andcommon public. The second edition was celebratedat the Central University of Caracas, Venezuela in2005, and now, in its third edition, it will becelebrated simultaneously with the IASS 2008Symposium, Acapulco, Mexico (InternationalAssociation for Shell and Spatial Structures).This symposium is organized by the Red
Latinoamericana de Tensoestructuras (LatinAmerican Working Net of Tensile Structures),whose objective is to promote and stimulate thedevelopment, design and construction of tensilestructures, by means of creating a discussion forumon these topics for researchers, professionals,enterprises and students.
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editor: Professor R. Motro
published quarterly
ISSN 0266-3511
The aim of the journal is to provide aninternational forum for the interchange ofinformation on all aspects of analysis, design andconstruction of space structures.The scope of the journal encompasses structuressuch as single-, double- and multi-layer grids,barrel vaults, domes, towers, folded plates, radardishes, tensegrity structures, stressed skinassemblies, foldable structures, pneumaticsystems and cable arrangements. No limitationon the type of material is imposed and the scopeincludes structures constructed in steel,aluminium, timber, concrete, plastics,paperboard and fabric. The journal aims atstriking a balance between theory and practiceand creating a platform for exchange ofinformation between structural engineers,architects, civil engineering contractors, systemmanufacturers and research workers in academicand non-academic establishments.
The journal includes regular reviews of technicalpublications, books and trade literature. Alsoincluded is information on recently builtimportant space structures, recently heldconferences and forthcoming events of interest.The Journal also publishes Special editions.
One of the forthcoming Special editions will be“Tensioned membrane construction”. Papers inthis Special Edition were selected from over 40 presented at the TensiNet AssociationSymposium “Ephemeral Architecture: Time andTextiles” held at the Politecnico di Milano, in 16-18 April 2007. They cover a wide range oftopics, from Campioli, Mangiarotti and Zanelli’shistorical review of textile architecture in theItalian context, and Hennicke’s inspirationalaccount of relationships between lightweight and natural structures and tensile architecture, to the more mathematically analytical approachin Gosling and Bridgens’ presentation of a newconcept for materials testing of architecturalfabrics and Wagner’s paper describing simpleanalytical design/checking tools for single/double-curved membranes and inflated cushions.To complement these, Adriaenssens examinesthe feasibility of spliced-spine stressed medium-span membranes and, as a practical case study,Stimpfle describes the redesign and installationof the Velodrome roof in Abuja, Nigeria.
For more info see www.multi-science.co.uk/space.htm
INTERNATIONAL JOURNAL OF SPACE STRUCTURES (IJSS)
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‘Futurotextiel 08’, an association of science,technology, art and textiles, is inspired by thecraziest dreams and invents today our dreams oftomorrow. The exhibition co-organised bylille3000 and the town of Kortrijk is being heldfrom the 9th of October to the 7th of December2008. It shows the concrete visions of tomorrow’stextiles, which will change our relationship withthe world, our environment and ourselves. Thefirst ‘Futurotextiles’ exhibition was held in 2006at the Tri Postal in Lille. More than being anexhibition, it embodies the realisation ofessentially European research being developed inthe world of textiles. For the reader and visitor, itmeans the discovery of the world of textiles, ashe/she appreciates its incredible diversity, fromthe fibre or weaving and the stitch to thecomposites and non-woven materials.The origins of the fibres are sometimes strange: a crab’s carapace, a basalt stone or beetroot givebirth to a fibre, thread or tissue.The new fibres seem to have emerged directlyfrom science fiction. Interactive and intelligent,they are subjected to different techniques ofcoating, dressing and micro-encapsulation…Whether cosmetic or therapeutic, the‘biosensorial’ textiles alter their physicalproperties according to environmental conditions,becoming anti-bacterial, thermoregulatory,hydrophilic, therapeutic…In this discovery of the world of textiles, alsobuilding and architecture receive particularattention.
Buildtech – Textile ArchitectureSince the dawning of time, woven materials havebeen used for the construction of all sorts ofshelter: small ones (tipis), adaptable ones(canvas), transportable ones (circus marquees),large canvas covers (the Velum in the Colosseumof Rome), simple sunscreens (parasols) or even
thermally isolated buildings (yurts). Since themiddle of the 20th century, several architects (Frei Otto, Bodo Rasch....) and engineers (HorstBerger, Jörg Schlaich...) have granted technicaltextiles a real place as a fully-fledged buildingmaterial, just like the reference materials of stone,steel, concrete and glass. The main added valueprovided by technical textiles is their lowerweight. Textiles from natural fibres have a limited lifespanand solidity. The use of new synthetic fibres,coatings and surface coatings, enable thetechnical textile to respond to the specificdemands in the following areas: texture,appearance, colour, flexibility and transparency,differentiated reflection of radiation, self-cleaning,acoustic and thermal insulation, high strength,weld ability and finally, the integration ofphotovoltaic cells. In terms of lifespan, dependingon the material and environmental conditions, areliable period of 20 to 35 years is predicted,without the appearance of any kind of problems.The textile becomes a multi-functionalcomponent, which is adaptable or re-adjustableaccording to the application to which it isassigned. Ongoing exploration on the quality andperformance is triggered by collective research(www.contex-t.eu) and thematic networks(www.tensinet.com).Evidently, the textile remains a supple support. Inorder to be inserted into a building it is forced intodouble curvature. Tension is applied to the wholesurface (like in an open umbrella) or by means ofinternal pressure (like in a balloon). The forms are‘forms of equilibrium’, in the image of a spider’sweb or a soap bubble, capable of adhering to anysurface.
The pioneers of architectural textiles emphasiseexpressive curves and unusual constructionsThanks to an adapted curvature, it is possible totransfer the loading pressure efficiently to thesupport points. Nevertheless, the tendency istowards constructions that are barely curved.These are realisable, when the material issufficiently pre-tensed over shorter distances. In addition to progress in the world of technicalfibres and their coatings, an improvement hasequally been attained in calculation techniques aswell as software tools. Architects, engineers,manufacturers, builders and entrepreneurs allhave access to specialised computer programmesand systems for analysis and design. In order to obtain a satisfying result, it is essentialthat all the players in the project collaborate fromthe outset. Transport, assembly and anchoragefactors must equally be integrated.Tensioned textiles are used for diverseapplications in construction. While in the 1930s,architecture concentrated on ephemeralconstructions, ever more ‘permanent’ projects areinitiated in shopping centres, cultural buildings,stadiums, schools, etc. In the current tendency, tensioned textiles canfulfil the demand for more curved forms. Withtheir natural shapes, architectural textiles caneasily find their place beside the massive volumes,where, thanks to their lightness (both physicallyand figuratively), they are capable of creating acontrast beside more imposing structures. Textilescan also facilitate reconciliation between newercreations and what already exists.
Marijke Mollaert for futurotextiel08www.futurotextiel.com
FUTUROTEXTIEL 08
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Buitink Technology fabricates andinstalls transparent inflatable globeand giant lightweight mirrors in theatrium of the Justus Lipsius Buildingin Brussels (Belgium)
Since July 2008, France has thePresidency of the Council of theEuropean Union. For the design ofthe interior of the EU buildingJustus Lipsius in Brussels, the Frenchgovernment contracted the wellknown French architect agency‘’Dubuisson Architectes’’ inCourbevoie (France).
An important part of the design is ahuge transparent globe (15mdiameter) in the middle of theatrium that is printed with thedifferent flags of the members ofthe European Union. This globe ishanging in the middle of the atrium,with at both sides a giant mirrorwith a size of 12m x 10m.
The transparent exterior features28 coloured strips which reflect theflags of the Member States and theEuropean Union. These suspendedstrips, which twist in spirals around
the globe, have been printed intranslucent inks (except the whitewhich, for technical purposes, ismore opaque) to enhance theglobe's transparency and heightenthe overlay effects. They not onlyreflect the individuality of eachcountry, but also create an overallharmony through the combinationand juxtaposition of the colours inan upward movement.The reason for placing the two hugeinclining mirrors on either side ofthe globe becomes apparent at akey point at the very heart of thefoyer. Anyone crossing the foyerwho stands at this point under theglobe, can glance up and see thelogo of the French Presidency
reflected in the mirrors against thecoloured strips. From this focalpoint, the globe fills the wholespace of each mirror.
In the top of the globe, a ring withLED lighting is installed, that lightsthe different flags in differentcolours.
The globe is made from a strongand transparent ETFE film. Theglobe is kept under pressure by anautomatic air system.
The two mirrors of 10m x 12m aremade of aluminium frameworks,which are cladded with alightweight (80g/m2) mirror film.
Originally there was a metalamphitheatre that was destroyed in a storm wind. The idea was to rebuild it with a more functional roof for the scope.The new construction is amembrane tensioned over 2 longitudinal reticulate arches, with 28m span each one, stabilized by 3 structural linesanchored to the floor and givingstability to the entire roof. The membrane is attached to thestructure with ropes.
The objectives of the new roof arethe following:
1. The need for a special design that is more suitable for theamphitheatre, that works betteracoustically and that achieves best visual effects of the show,either day or night through thelighting of the shows;
2. Low building costs;
3. Rain protection;
4. Easy installation and the need fora demountable structure.
Finally was chosen for a prestressedPVC-membrane on the basis offollowing two reasons: 1. It strictly complies with all theobjectives;2. When compared to othertraditional systems such as metal orconcrete construction, thesetraditional systems do not meet allthe requirements, not offering theaesthetic and formal opportunitiesPVC membranes can offer.The roof has been designedrespecting the minimum height to
develop shows, and generating amembrane with double curvature toencourage the good diffusion of thesound for the spectators. The structure and the membranewere designed at the same time. The metal structure is made ofarches in round pipes 5" and 2" andthe anchorage in Platinum in 1". The membranes are made ofpolyester fabric (PES HT 1100dtex,5x5 threads per cm (12 threads perinch) with PVC coating, UVprotection on the outside, a weight
Figure 1. Inflatable globe
BUITINK TECHNOLOGY FABRICATES AND INSTALLS
TRANSPARENT INFLATABLE GLOBE AND GIANT LIGHTWEIGHT MIRRORSIN THE ATRIUM OF THE JUSTUS LIPSIUS BUILDING IN BRUSSELS (BELGIUM)
AMPHITHEATRE OLIMAR
Figure 3. Installation of the globe and mirrors
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In 1992, on the occasion ofan international expositioncommemorating the 500th
anniversary of thediscovery of the Americasby Columbus, the oldharbour of Genova and thehistorical city district(which had long beenseparated) were rejoinedthrough redevelopment. Old 16th century buildingswere restored and anaquarium and the Bigo(bigo is the old Genoveseword for a ship's crane)were newly reconstructed.After the exposition ended,the facilities were turnedinto a large waterfrontpark and have since beenadministered by the city.
The tent roof (60m long by 40m) covers a multi-functional space: after the exposition, it has served as a skating rink inwinter and a place where miniature soccer games for children or outdoorconcerts are held in summer. The Bigo consists of 2 independent sets ofcigar-shaped booms forming out from a small island located within thewater of the dock. One set of booms supports the membrane roof and theother carries a vertical cable-car passenger lift from the quayside. Both setsare anchored down with tie bars to foundations beneath the harbour water.
Radiating out from the tip of each of the booms supporting the canopy arefans of 16 cables which support slender arch ribs from which in turn themembrane canopy (made of PTFE-coated glass fibre) is suspended. The canopy consists of 5 discrete membrane panels each of which has ‘edgecables’. Glass lenses close off the gaps between the membranes while apantograph mechanism automatically synchronises the position of the glasswith that of the membrane roof under changing loads.The Bigo, built 16 years ago with a PTFE-coated glass fibre fabric, is still a nicely tensioned,clean white, impressive free span cover and one can feel that this preciselyengineered structure performs well. Roberto Canobbio would just preferthat the steel structure could be painted to ensure an extended life time ofthe whole structure.
of 800gr/m2 (230oz/sqyd) and a breaking load limit of 30daN/cm.(167lbs/inch). The prestressing of the membrane has being done manually with a rope tied to the structure.Everything was manufacturedin the workshop in 30 daysand the assembly took placein 10 days.
The objective sought after bythe roof was achieved toperfection, accomplishing anenjoyable space for holdingshows.
Name of the project: transparent inflatable globe and giant lightweight mirrors
Location address: EU building Justus Lipsius, Brussels, BelgiumClient: Secrétariat Général de la Présidence Française
de l’Union EuropéenneYear of construction: 2008Architects: Dubuisson Architectes (Sylvain Dubuisson),
Courbevoie, France (www.dubuisson.fr)Engineer for the globe: Tentech BV, Utrecht,
The Netherlands (www.tentech.nl)Manufacture and installation Buitink Technology, Duiven, globe and mirrors: The Netherlands (www.buitink-technology.com)LED Lighting: Preview Lighting, FranceMaterial inflatable globe: transparent ETFE film
(from Nowofol, Germany)Materials mirrors: Aluminium frameworks and tensioned mirror filmDimension of the globe: 15m diameterDimension of the mirror: 10m x 12m
Name of the project: Amphitheatre OlimarLocation address: Treinta y Tres, UruguayFunction of building: amphitheatreYear of construction: 2008Architect: Susana MartinezDesign & project roof: Roberto Santomauro & arch. Patricia PintoStructural engineers: Marella & PedojaTensile membrane contractor: Sobresaliente ltda.(www.sobresaliente.com)Material membrane: PVC-coated polyesterCovered surface: 355m²
Name of the project: BigoLocation address: Genova, ItalyFunction of building: covering multi-functional space
(skating rink, miniature soccer games, concerts, etc.)Year of construction: 1992Architects: Renzo Piano Building WorkshopEngineers: Ove Arup & Partners; form TL ingenieure für tragwerk
und leichtbau gmbhTensile membrane contractor: Canobbio S.P.A. (www.canobbio.com), ItalySupplier of the membrane material: Verseidag-Indutex gmbhMaterial membrane: PTFE-coated glass fibreCovered surface: 40m x 60m
VISITING THE BIGO
Figure 2. Reflection of the globe in lightweight mirror
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MEMBRANE STRUCTURES
IN INDIA
The following current trends in the construction industryin India can be observed: a need for contemporaryarchitecture, an interest in landmark projects forMultinational Industries and the ambition to buildprojects lined up for the future. A few recently completed projects are listed below.
IBM Food Court The food court building for IBM inBangalore is a unique combinationof glass, fabric and steel. Thebuilding houses various multi cuisinerestaurants, arranged on three levelsand connected by stairs. There arelarge continuous spaces and theconnectivity between these spacesenhances the feeling of height andopenness.Pre-fabricated components instructural steel were used toenhance the speed of construction.The roof cover is formed by pre-stressed PVC membrane panels -like the petals of a flower - that havebeen seamed together andstretched continuously between 2 ring beams. This roof provides anoptimized, two dimensional largesurface that is readily used for rainwater harvesting. Rainwater iscollected in the central open spaceand re-circulated. This offers aunique indoor-outdoorenvironment. The light translucencyof the roof provides for naturallighting during day time, therebyoptimizing the running costs of thebuilding. The façade does not have typicalwalls and windows but a PVC meshmembrane fabric that is tensioned
like the sails of a ship using cablesfrom the top level to the lower level.The mesh blocks the view from theoutside but lets the people insidehave a view to the outside. Thisfaçade in turn reduces the need forartificial ventilation and lighting. The structure displays excellentenergy efficiency and eco-sensitivity. The façade and the floor areintegrated by using thin roller decksteel floors that are supported bysleek steel columns and extremely
lightweight externalwalls. This structure can becompletely dismantled and erectedelsewhere!
This building received the INSDAG(Institute for Steel Development &Growth) award for the best steelbuilding in India.
Name of the project: IBM Food Court Location address: Bangalore, IndiaFunction of building: restaurantYear of construction: 2005Design and construction: Construction Catalysers, Pune, India,
[email protected], www.concat.inMaterial membrane: Valmex FR 1400 Mehatop F type IVCovered surface: 1780m², ø55mArea of building: 40000m²
The dam wall at Amby Valley doubles up for a two lane vehicular bridge. On one side of this dam are the serene backwaters of the Lonavala valley andthe other side is adorned by a Sail Sculpture. This unique Sail Sculpture is an array of 24 membrane modules. Each moduleis 14m high and 9m wide. The arch girders are made from steel plates with the provision for pedestrians to move besides them. With coordinated light projections at night, and a very proud stance throughthe day, the large sculpture stands witness to the serenity of the valley and
the human activityin the township. Thesculpture acts as anaestheticallyengineeredbackdrop to the10km longdevelopedwaterfront and thesculpted beauty ofthe igneousSahyadri mountainsin Lonavala.
Sahara Sails Sail Sculpture on a Dam Wall
Name of the project: Sahara SailsLocation address: Amby Valley, 70km east of Mumbai, IndiaSculpture: Sahara SailsYear of construction: 2003Design and construction: Construction Catalysers, Pune, India,
[email protected], www.concat.inMaterial membrane: Valmex FR 900 Mehatop F Type IISurface: 1500m²
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Tensile Rotunda at Unitech Rohini A unique tensile membrane structure is used as a sunshade for a roundsymmetric pedestrian staircase and a bridge. The membrane structure ismade of a mesh type fabric that renders a free shadow over the spacebeneath. The entire membrane is stretched at an offset height of 3m abovethe round bridge at 11 points. A principal hoop cable is provided at the innerside of the membranethat stretchescontinuously from the top of the clock towerspiraling down to theground towards thebasement. Due to thehigh edge forces on themain inner cable,secondary cables are used within the fabricedge seam that transmits the forces to the main cable at every 3m.
Sacred World A Truly Tensile RoofIn a hot tropical country like India tensile membranes are ideal forprotection against heat and rain. Membranes can control the transmissionand reflection of sun light. The Sacred World tensile roof has an ellipticalshape in plan. The entire membrane is suspended on two cables with an eyeshaped opening created by the crossing of two structural cables. This shape of the opening that evolved from the form finding process iscovered with glass panels giving direct light in the atrium below. This unique, eye shaped glass opening provides curvature in the continuouslarge fabric surface, thereby creating an aesthetic value to the eye, as ametaphor opening to the sky. All components of this roof structure are 100% in pure tension. Each and every member carries tension, thereby making it a truly tensile structure.
Membrane structures are particularly suitable to a developing country likeIndia because they can be applied to a variety of spaces like transportterminals, car parks, shopping malls etc. They are economic structureshaving an immense potential!
Name of the project: Sacred WorldLocation address: Pune, India Function of building: Mall/atriumYear of construction: 2005Design and construction: Construction Catalysers, Pune, India,
Name of the project: Tensile Rotunda Location address: Unitech Rohini, Dehli, IndiaFunction of building: Sun protection for staircase and bridgeYear of construction: 2004Design and construction: Construction Catalysers, Pune, India,
[email protected], www.concat.inMaterial membrane: Mesh fabric, Ferrari
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AbstractFast changes have occurred in the past few yearsas to the utilization of textiles both inconstruction and architecture. These materialsare employed to create special roofing meant toobtain great luminosity or for specific purposes.Textiles have become something to “make”architecture, something – being very adaptable –capable of satisfying various requests and ideasexpressed by the designers.As a result, the role of the manufacturer hasbecome more and more significant because, onone hand he is requested to keep in closecontact with the producers of the textiles whichare relentlessly evolving; on the other hand he isrequired to develop new construction proceduresin order to satisfy the various and sometimespeculiar requirements of the designers.
PreambleThe field of tensile structures is continuallyevolving and most technologically advanced inthe construction industry. In the last 15 years – inEurope – its revenues have increased a great deal.Since 2001, the work of TensiNet and its partnerswho have organized meetings and seminars turnsout to be very important when one considershow much and how fast the idea of constructionwith the use of textiles has evolved. FromUniversity students to the laymen the awarenessand knowledge of this type of construction isquite perceptible.In short, this “technology of lightness”, alwaysconsidered being highly sophisticated and almostimpossible to be utilized without specificacquaintances and proven experience isgradually becoming more popular. However, aconstant updating becomes imperative in orderto offer to all concerned information concerningnew materials and technicalities.
1. DESIGN AND CONSTRUCT A TEXTILE STRUCTUREIn this particular field of operations themanufacturer, because of his unambiguous role,is involved in the project from the beginning(design and detailing) to the end (manufacturingand setting up).
Design: The architect is required to set up ageneral layout, to establish the geometry and tochoose the materials to be utilized for theconstruction in order to answer to the requestsof the client. The first draft is followed by thedesign drawings. Often however, the finalstructure size must fit the layout and thecalculations of the structural engineer. The tensioned minimal shaped membraneexpresses beauty in the play of shade and lightand provides a sheltered space; it is water andwind proof and, at the same time, put up with all structural forces. If well shaped, thesemembrane structures can cover wide areas andlarge areas with a minimum effort in terms ofmaterials.
Detailing: The form of a tension equilibriumstructure follows the laws of Physics and finds itsminimal surface within defined boundaries. The art of ´designing´ membrane structures isthe art of controlling their boundary conditionsand controlling their support geometry, based onthe knowledge of the physical properties oftensioned equilibrium forms, and the search ofthe best shape to suite the scope. The architectexpresses his ideas and it is the structuralengineer together with the manufacturer whochooses the most suitable material.This choice is made bearing in mind how eachmaterial reacts and the correct compromisebetween aesthetics, safety, durability and costs.Luckily, nowadays we are in a position tocompare a wide range of materials as from thetable hereto:
All the other items required to complete amembrane structure such as masts, cables,arches, foundations, pillars, walls required tocomplete a membrane tent are made of steel,wood and concrete as in conventional buildings. To obtain a lightweight structure it is necessaryto apply high construction standards concerningmaterials and a very dedicated design process,especially when the lightweight structure isintegral part of conventional buildings.The main difficulty is produced by theprefabricated elements to be assembled on sitewhich must be well defined and must agree tothe 3D geometry and the forces to which all theitems are subjected to in order to grant stabilityto the structure.
Therefore, fabric and cables are to be madewithin reduced dimensions in comparison tothose finally intended so as to allow thedevelopment of appropriate strains during theassembling process.
Manufacturing: Having established thatthe people involved in the design process mustwell know the materials and their use, one cansay it is not the case of finding a manualdescribing how to make tensioned equilibriummembranes. The architects must compromisepractical, scientific and philosophical concepts.The manufacturer must conciliate with all theabove in addition to the requirements of theclient, the architects and the structuralengineers.
But what does a production process mean inpractical terms? Check if the selected material iseffectively suitable (according maybe to previousexperiences); determine which welding systemto adopt and the dimensions of the welding;define the cutting lines; flattening of the stripes;determine the de-compensation factors;dimensioning of the edge details in order toallow for an easy connection with othermaterials such as cables, section by section orprimary structure; cutting; check of thehomogeneous characteristics of the materialused; welding; insertion of details; check; folding;transport and installation.
The criteria used to check if the selected materialis effectively suitable are the following: tensilestrength; constructive typology; durability; fireresistance behaviour; warranty; flexibilityaccording to folding and installationrequirements and others…
At this point it is necessary to compare thecalculated stress values with the strength of theselected material. This is why the strength of thematerial is required according to this heading:strength of the membrane material, strength ofthe seams and tear strength.
DESIGNING, DETAILING AND BUILDING WITH TEXTILES. Projects realised with different fabric.Special Guest Lectureat Textile Roofs 2008
Type of welding HF HF with HF with Hot bar Hot bar Hot barabrasion with abrasion with FEP with tape with tape
Realisation cost Very low Low Low High Medium Very High
Mobile Architectural Architectural Permanent Permanent ArchitecturalRecommended use Industrial Temporary Temporary Important Structures Retractable
Structures Structures Structures Structures
✳ unsatisfactory ✳✳ fairly good ✳✳✳ good ✳✳✳✳ very good ✳✳✳✳✳ excellent
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Installation: During the erection procedure,details and connections must take into accountthe movements and rotations that will occurduring the lifetime of the structure and in manycases must also foresee the particular rotationalmovements which can happen during erectionespecially for mobile structures which arecontinuously erected and dismantled. If this isnot taken into account, the details will bedamaged or destroyed. So the erectionprocedure must be investigated carefully todiscover the needed rotational capacity of theconnections.
The tensioning part also plays a very importantrole. We must take into account if it is possibleto pretension the structure by means of thechosen detailing, or if there are temporaryadaptations required, and if there is enoughadjustment left for future purposes.It is not enough to realise a correct design, tomake a nice and precise structure, to use verygood materials; erection is a particular stage ofthe whole work: you need experience, knowledgeof the components, of the site, but above all youneed a trained and experienced erection team.Any detail is to be taken into account in order toinsure a perfect functionality to the newarchitectural structure.
Responsibility: Normally the fabricmanufacturer is responsible for the seam and itsstrength. On the other hand the seam strengthdepends to a great extent on the bonding
strength of the coating on the fabric, for whichthe coating firm is responsible. There is thus splitresponsibility here. The consequences of thismust then be explained as follows: the coatingfirm shows what can be achieved by optimizingits technology of bonding the coating onto thefabric. Besides all this it must be taken intoaccount the influence of the short term loads, of the temperature and of the permanent loads.
2. PROJECT OPPORTUNITIES AND RECENT EXAMPLES
After Renzo Piano had utilised tensile structuresin the 90ies – the Bigo in Genoa (see page 5), the Bari Stadium in Italy – which offered old andunrivalled utilization of textiles, it seemed tohave unjustifiably abandoned this type ofmaterials and technology despite theconsiderable know-how by the Italian companiesoperating in this field of manufacturing andalmost completely ignored by our architects andengineers.
At last, thanks to the various encounters andexchange of information within Europe regardingthe development of technology of themembrane tensile structure – TensiNet Network– we can happily say that the architects andstructural engineers experiences in this themehave now produced a significant progress in linewith the progress of the technology itself andthus are in a position to be the fore front fordesign and novelty.
In fact, in 2006 and 2007 we have witnessed arecovery in Italy as well and from two points ofview.
In some cases, described in detail below, Italianarchitects and engineers have opted for textilematerials rather than more traditional ones forroofing and/or wrapping. As an example, thegrand tensile structure made of steel coils andpolyester/pvc membranes at the new Rome Fair,built in 2007, by architect Tommaso Valle andengineer Massimo Majowiecki. And again, to themost recent multifunctional covering ofChianciano Terme, a novelty aerated roof madeof tensile structure membrane designed byarchitect Paolo Bodega.
In other cases, Italian architects have designedmembrane structures for works erected abroadthe fame of which rebounded in Italy as well. Forexample the temporary Finmeccanica Standmeant for international exhibitions, designed byStudio Gris of Padova and the 12 000m2 of theorange textile with which architect MassimilianoFuksas has wrapped the largest auditorium inEurope: Strasburg Zenith, recently inaugurated.Provided that the various projects entail differentdifficulties, it is noteworthy to point out that theknow-how as well, can encounter chances fornovelty and improvements through various andsometime improbable routes. It is the case ofprojects apparently simple or almost routinelywhich entail the use of textiles most commonlyutilized and well known as we shall try toillustrate better through the issues that follow.
The cutting shape of the individual stripesis determined geometrically from thesurface area and the warp and weftorientation. The warp and weft orientation mustbe defined taking into account the static analysis.We can divide the patterning generators in twomethods i.e. the radial or parallel distribution. Fabrication patterning has to be accounted forexplicitly within numerical models for bothform-finding and analysis of prestressedmembranes. Their doubly curved surfaces aremanufactured from flat unstressed panels ofcoated fabric with seams usually made by highfrequency welding or hot bars. For reasons ofmaterial economy and accuracy, and to avoidwrinkling in the surface form, the centrelines(and seams) of panels should follow geodesicpaths over the surface. These geodesics are thetrajectories which a flat tape of material couldfollow without shearing: The directions of thefabric weave, with warp along the panel and wefttransverse, are dictated by the patterning andyet the prestresses specified in these weavedirections govern the surface shape. Thus theintended weave directions for patterning mustbe taken into account during form-finding. Thesame clearly applies to modelling the stress /strain relations of the weave during load analysis.From this the cutting patterns are calculated. It isalways important to consider that themembrane is under prestress which causes itselongation. It is therefore necessary to correctthe cutting pattern by this elongation and thisstep is called compensation. We have now come
to another necessary production step:compensation in the cutting pattern. For this weneed either the relaxation (under fixed boundaryconditions) or creep behaviour (under boundaryload conditions) of the membrane material. It istherefore necessary in effect to anticipate thedeformation which is likely to occur over the lifecycle. For this purpose defined stress histories areestablished and after working through these thecompensation data can be read off. At presentthere are still no fixed rules for compensationtrials. To determine those compensation factorsit is necessary to undertake some biaxial testsfrom which we can find out the compensationrequired. We also have to take into account byusing those reductions in percentage of thematerial the edge details or the fixing of stifferelements. In this case the compensation factorswill be reduced to a minimal value to allow thejoining of different elements. All this is done with appropriate software whichgenerates command files to an automaticcutting table. During the unrolling of the fabricthe material has to be checked by means of alight table in order to avoid aesthetical andmechanical defects which have to be avoided byeliminating the defected material. Once the material is laid on the cutting table andthe nesting has been fulfilled to avoid waste ofmaterial, the automatic cutting starts to cut theboundary lines and to introduce marks necessary
to locate the single stripes and thedefinition of some details and intermediate marks in order to verify
during assembling the maximum precision. For the assembling phase we can use differentkind of welding machines. It is thereforeimportant to make a few preliminary tests forthe seam resistance in order to obtain the samewelding efficiency. Those tests are executed byinternal labs at 23°C and 70°C. The weldingconfiguration parameters are established by anautomatic system which is in the machine itself.During the production phase we make few teststo verify the homogeneity of the resistancevalues of the seams. During welding together it is also important to take account of the factthat the membrane material shrinks duringwelding. This can be compensated by eitherallowing for this welding shrinkage during thecutting out process, or by carrying out thewelding under stress and then hold this stresslong enough for the material to cool. These two methods are possible by using fixed machines or mobile machines. After the assembling process has beencompleted and the length of the boundaryborders are verified we proceed with theinsertion of the membrane details, double layersof membrane, reinforcements, holes and so on in order to complete the manufacturing process. All those insertions must be executed taking into account that the lengths of the edges aredifferent with respect to the lengths of themembrane during its manufacturing.
From stripes to 3D tensioned surfaces
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Open buildingsRight from the beginning, the light weightproperty of textiles and membranes, havesuggested their use in the case of wide spanareas (such as the case of Trade Fairs andExhibitions) for which roofing and not thermal oracoustic isolation entails priority.Some recent works stand todemonstrate that thisphilosophy is still paramount toother ideas, yet at last, tensileand pressure structures havefound new openings, almost anew age, as they are beingutilized in non conventionalsituations, side by side or inplace of, or as an essential partof other and more traditionalmaterials and buildings.
Figure 1. Garage Park, Montreux
The most important example is the covering ofthe Garage Park in Montreux (Figure 1) whichproposes a new skyline for a textile roofing andturns into a gleaming landmark in the nightnoticeable from distance.
Closed buildingsNowadays a vast range of utilization of themembranes is opening up for architecturalprojects. It is no longer the case of roofing only,but the application of an integrated system i.e.vertical (walls) and horizontal (roofs) in line withthe modern “language” adopted by thedesigners. This trend, meant to value free formsof expression, is made easy on one side by theuse of CAD systems which enables exchange ofinformation among those involved in therealization of intricate works and, on the otherside by CAM producing process of industrialapparatus thanks to which different items interms of dimensions and morphology can beattained. Within these wider technical prospects,the designer seems to enjoy great freedom inmatching materials and building items and assuch can attempt on new materials, new devicesand their interconnections.
A nice example of the utilization of the Tenara®fabric is that concerning internal works: an aspect of construction yet seldom employed,but suitable of interesting future developments.More and more often, public buildings are multi-purpose constructions. The need to create smaller spaces within theirstructures becomes therefore necessary: spaces intended for specific purposes. In this instance tensile structures can become asuitable solution. It is the case of the workscarried out by architects Giancarlo De Carlo andMonica Mazzolani inside Pesaro Palazzo diGiustizia (Figure 3) in 2004.
Figure 3. Palazzo di Giustizia, Pesaro
A single layer of PTFE transpiring fabric wasemployed as the main purpose of the job was to create an enclosure, lighted by the sun rays passing through a roof window. It is thanks to the properties of the membranethat the light – excellent for readers – can passthrough and yet shields them (the readers) from external activities and possibledisturbances.Additional advantages granted by the use of this specific construction choice must beunderlined: the tensile structure membrane isapt for the creation of a continuous surface, a peculiarity of the flexibility and easy handling of the textile, allows for a fast andsimple installation of the internal metal structure and, due to its light weight, thecalculation for the structural stress becomesludicrous.
A dismountable closed building: the new Tea House MAK, Frankfurt am Main, 2007
The new Tea House (Figure 2) designed by architect Kengo Kuma is innovative in term of form,but above all in term of materials utilized and solutions adopted. It is the outstanding exampleof how a project evolves in the hands of the various operators involved during the design processas Arch. Gerd Schmidt from Form TL describes it: “The inflatable Tea Pavilion of the “Museum fürangewandte Kunst (MAK)” was as a kind of joint between sculpture and temporary room forceremonies.It is a gift by Japanese companies to the city of Frankfurt and especially to the MAK which hasvery tight connections to Japan because of its far eastern collection.It is unusual that from the beginning Kengo Kuma has chosen modern material. While wood andsliding walls were left out, a hint of diminutive bamboo is found at the base of the pavilion.Tatamis, although made of easy-to-clean synthetic material, the low ceilings and the even lowerdoors as well as the zoning and the counter-sunk fire-place have been kept by Kengo Kumaduring the whole design process.Even on his first drawings he showed a smoothly shaped double-bowl structure which wemodified and specified during monthly meetings. At the end the organic shaped structure withmembrane cover became a self-carrying double-wall pneu with minimized assembly anddismantling times – and it fits into the budget of Japanese sponsors and the museum. Because of its shape the Teahouse got the working title “Peanut”: a cover of 80 m² encloses witha distance of 40-100 cm an about 60 m² cover. At the footprint the two covers are air-tightlywelded together and 3-4 times per m² joined together with thin synthetic ropes between whichthe air is blown in, similar to a dinghy or water wings.But instead of membrane stripes like they are used for inflatable mattresses the two covers areonly point wisely joined which leads to a golf ball shape and defines the texture of the inner andouter surface. The stability of this flexible bowl is formed by the size of the footprint, the internalpressure and the number of joints. From 1.0 kPa internal pressure the “Peanut” stands up andwith 1.5 kPa the flexible bowl is stable enough to face a storm. The blower is dimensioned for 2.2kPa so that there is enough capacity for the air. We had to take into account that after severaltimes of assembly and dismantling the leakage of the cover will raise therefore the blower got avariable regulation so that the leaked supporting air can always be added. Another bigadvantage is the soft blower noise which allows a use inside the entrance hall. Although the Modern Teahouse seems to be thin-skinned and sensitive, it is not because of theTeflon fabric which is inured to kink. It survived the run of thousands of visitors at the day of the
inauguration and as well several times ofassembly and dismantling.”
Architects: Kengo Kuma, Giappone Engineering: Form TL, Germany Manufacture Canobbio, and installation: Italy. Material: Tenara®
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A temporary building: Finmeccanica Pavilion Farnborough, 2006
If Tenara® is a fairly new material, polyester/pvc is a more traditional and widespread item. Its utilizationhowever, constitutes an experiment as is the case of the covering of Finmeccanica’s temporary stand(Figure 4). For the “Finmeccanica Pavilion Farnborough” cushions were made of a transparent PVC foil on theoutside and a white PVC-coated polyester fabric on the inside to grant a reflecting effect of sky andclouds during the daytime and light during the night-time. The futuristic architectural design has strikingfeatures that communicate in unusual ways. The oval-shaped structure measures 1000 m2 with another300 on the upper level. The shape of the pavilion follows curved lines in plan and section creating aunified and flexible image, smooth and rounded everywhere, intensified by the air-filled internal andexternal cladding. The smoothly sculptured shape creates a continuously changing appearance whichcatches your eye every time you look at it. (see also TensiNews 11)
Client/ Building owner: Finmeccanica ItalyMembrane design: form TL ingenieure für tragwerk und leichtbau GmbH, GermanyMembrane manufacturer: Canobbio S.p.A., ItalyMembrane and façade: roof: 1250 m2, roof cushion: PES/PVC Type 1,
Façade cushion outside: transparent PVC-foil, Façade cushion inside: PES/PVC Type 1 Farnborough Air Show 2006: 17-23 July 2006
An impressive façade: Strasbourg Zenith, 2007 The most recent example of how architectsintend to promote new employment of textilesis that of Strasbourg Zenith (Figure 5), designedby Arch. Massimiliano Fuksas and completed inDecember 2007 described from “Arketipo”magazine by A. Zanelli: “The new Zenith inStrasbourg was opened last January and it hasset the record with its 10 000 seats of thelargest concert hall in Europe. The musical hall isdesigned as a dark core protected by a hardshell that is moulded on the lines of differentcurves’ radii that have been studied to optimisethe ratio between maximum capacity and bestview; this core has been built in reinforcedconcrete to better control the acousticperformances.The envelope is instead quite light, coloured,translucent and textile: with this design decisionFuksas seems to rekindle a connection with thematerialism of the first two Zenith projectscompleted in by the architects Chaix and Morel.The first Zenith was completed in Paris in 1984and the second one in Montpellier in 1986; theyare both composed by a metallic frame with amembrane-like cladding. This thin skin is of an orange colour, it issensitive to day light and it can lit up in thenocturnal landscape and through its use Fuksashas re-created in Strasburg the magicalatmosphere of the travelling shows and theirtransient sensation that can be felt under theircharacteristic tents; however at the same timethe architect has opted for the internal hall for amore permanent construction in reinforcedconcrete to be able to achieve the best acoustic
and visual qualities. The new auditorium Zenithhowever doesn’t show the compromisebetween two technical solutions that are sodifferent with regards to their constructionmethods as well as their weight and lighttransmission properties: a continuous in-situreinforced concrete shell completed in 18months and a tensile structure assembled offsite and erected in 10 weeks. The project has thecharacteristics of a happy union and of a trueand proper technical and constructiveinnovative design. The plastic and static shapeof the concrete shell is wrapped by five steelelliptical rings that are vertically spread withdifferent eccentricities. The orange fabric isconnected like a tape to the steel rings as wellas to thinner tensile cables and shrouds thelarge hall getting closer and further from theconcrete shell creating an intermediate spacethat is full of dynamism. This whirling fabricentanglement is ruled by 22 steel masts thatgive the perception of being pushed outwardsthe concrete shell by the hollow steel tubes thatare anchored to the shell itself and that presentdifferent lengths; in the same way theinclination of the masts varies with regards tothe external perimeter of the tensile structure.The novelty of this architecture consists inhaving overcome the typical skyline where allthe tensile structures seems to be condemnedfrom their initial static concept of “form-resistant”: there is no trace here of thecounterpoint between the tall columns (themasts) or of the low fixing point (valley cables)or of the ridges and valley fabric profile.
For this project the inclined masts represent theoriginal connection between the concrete andthe fabric and they dictate the rules for thedefinition of an architectural space thatwelcomes the audience at the entrance andsurprises them for full-height views withmultiple depths. The fabric assumes a double curvedstrengthened shape created by the overlappingof elliptical steel cables that act as valley cablesand by the stiff ellipses of hollow steel tubeseffectively replacing the ridge rings. The sinusoidal profiles needed to satisfy thestatic constraints of the membrane tensilestructure have been completely re-interpreted:they present themselves as sudden changes inthe direction of the fabric that externally isperceived as a single orange surface chiselled by recesses and projections that are curved onthe horizontal surface but sharp on the verticalone. The Zenith is Strasburg is a clever synthesis of architectural research carried out at multiple levels and supported by equallydiversified competencies. The choices made by the architectsMassimiliano and Doriana Fuksas have beenaddressed and turned into a built environmentby the contribution of a number of specialistsfocussing on: the study of the reinforcedconcrete shell, the design of the steel elementsof the tensile structure, the dimensioning andinstallation of the fabric panels and the acousticengineering.”
This area can also offer some possibilities ofdevelopment. The transformation of a building iseconomical if executed within a very short periodof time. A recent example is that of the coveringof Tenerife Astronomic Observatory (Figure 6),designed by Eng. Pedretti of Airlight,experimentally installed at Castelnuovo Scrivia –
CAMECfactory – and recentlyerected atTenerife.Sometime it isthe welldefinedpurpose of abuilding whichcan suggestthat nomodificationcan take place
and nothing new can be tried; on the contrary, itis because of the simplicity of the theme – in thiscase an astronomical observatory – that couldadvocate that the time to acquire newacquaintances, in this case the opening andclosing of a structure which is made possible bythe power of pressurization, has come. Two greatsteel arches lift and rotate around a central axispulling a polyester/pvc fabric which at the sametime inflates and pulls up the other smaller archesuntil it reaches the shape of a big pneumatic shell.The gigantic shell measuring 15m in diameterinflates in 7 minutes and more slowly deflates –pressed by the steel casing – thus causing thereturn of the two arches to their original position.At the end of the operation, the presence on theground of a building is hardly noticeable whereasthe telescopic equipment is free to turn for 360 degrees and from horizon level to the zenith.
Figure 6. Tenerife Astronomic Observatory
ConclusionThe projects described above were chosen toshow that the roads from the original idea to thebuilt project can be many and of different type,but all with a common need: that of the deepknowledge of that specific product of which themembrane architecture is made of: a textile, lightand transparent material. The designer could hold the knowledge or,sometimes the manufacturers can contribute tomake it known, but, whatever the case, it must bepresent and profound. The textile industryembraces a potential innovative power that canmake today’s achievements obsolete tomorrow.
Designers, producers, manufacturers andcontractors are all looking forward to ensuringthat new materials would enable textileconstructions overcome some limitations whichstill exist at present. For example, it is difficult tosurmount some climatic problems which areeasily solved by traditional constructions.
The utilization of a double layer membranesandwiching air or isolating materials is a possibleoption, but due to the 3D shape of themembrane, the negative effect on themanufacturing costs is rather high. This is why various European Communities backed working groups – such as Contex-T –
with a view to improve building performances bytrying to discover protection systems, films andchemical coatings in order to overcome today’s restrictions. Once found, these articles shall definitely help in maintaining themembrane structure characteristics (lightness)unaltered thus granting a wider scope ofutilization in the future.
Terme di Chianciano, Parco Fucoli, Chianciano, 2007
The modification should not be exclusively intendedin connection with the opening and closingoperations, but also regarding the suitability of thebuilding (or part of it) to season changes. This is thecase of the multi-purpose building designed by Arch.Paolo Bodega and erected at Parco Fucoli. Themanagement of Terme di Chianciano (Figure 7) haveapplied for a multi-purpose space: a wide cover togrant shade and breeze in summertime allowing theun-obstructive view of the surrounding park, yet aclosed building acoustically isolated to be utilized forconcerts and/or sport events. A double layer membrane tensile structure wasutilized so as to grant aeration as it is the case of atraditionally ventilated roof built with conservativematerials. By utilizing a two layer polyester/pvctextile, with dissimilar mechanical specifications andtransparency degree, the project minimizes fuelconsumption to produce heat in wintertime (closedbuilding + closed air inner space), takes care of theproblem to keep the building cool in summertime(open space and removal or folding of the closingperimeter cushions) and reduces solar overheating(the air is funnelled through grates fitted at the baseof the building and polycarbonate windows placed ontop of the Flying masts). The final result is that of a light structure whichthough fitted with a double layer cover, does notprevent clearness and in fact emphasizes it thanks toluminous spots placed at the foot of the flying masts.It is dry assembled thanks to the wise associationamong the various materials: wood and steel for theprimary structures, textile membranes for the cover,pressurized textile cushions for vertical walls,transparent polycarbonate for the roof windows.
Figure 7. Terme di Chianciano, Parco Fucoli, Chianciano,
Engineering of Studio Associatothe structure: Arti e Tecnologie,
ItalyEngineering membrane: Form TL,
GermanyProject management, Canobbio,manufacture and Italyinstallation membrane: Material: Double layer Polyester/PVC
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Rhino Membrane is one of the most powerfultools for form finding of tensile structures and yetmost simple to understand and use. An engineering team integrating research,professional software development and expertisein the field of tensile structure design, hasproduced a high-tech component with very fewlimitations. This Rhinoceros plug-in combines theefficiency of a modern finite element approachfor shape finding with the comfortable and easy-to-use graphical user interface provided by Rhino.The implemented features amongst othersinclude form finding of membranes with isotropicand anisotropic pre-stress, cable elements forcable nets or edge cables, pressure option forform finding of pneumatic structures and stressplots for evaluating the final stress distribution.Using a direct sparse matrix kernel, hugeproblems are solved in a fast and reliable way,plotting the intermediate non-linear steps onvideo makes it possible to choose anintermediate result for a future run.
TheoryThe theoretical background of Rhino Membraneis provided by the Updated Reference Strategy(URS) for form finding of membrane structuresdeveloped by Prof. Kai-Uwe Bletzinger of the TUMünchen (Germany) [1]. For a given topology of amembrane structure and a given stress state inthe structural elements (pre-tension in themembrane and cables), the correspondingequilibrium shape has to be determined. Withnumerical methods this shape finding problemcannot be determined directly, as an infinitenumber of valid geometrical discretizations withthe same mesh topology can be found for thesame equilibrium surface. There is no uniquesolution: metaphorically speaking, the FE nodescan “float” on the surface while still representingthe same equilibrium shape. Figure 1 illustratesthese floating meshes for a simple four pointmembrane with fixed edges. In order to stabilize the originally badly-posedproblem, the Updated Reference Strategy aims
for solving a series of related well-posed problemsand thereby gradually converging to the originalsolution. In the context of membranes this statesthat instead of prescribing the pre-stress on theto-be-found final geometry (Cauchy stress σ onthe current configuration x), a stress measurerelated to a certain given starting geometry forthe computation is prescribed (2nd Piola-Kirchhoffstress S on the reference configuration X). For thismodified problem, a unique solution can beobtained. Yet, as generally a deformation occurswhen the equilibrium shape is computed thestresses on the deformed shape will differ fromthe initially prescribed ones. This necessitates aniteration loop, which consists of a referenceupdate (the solution surface of step i will be the
reference surface of stepi+1) and a following formfinding step. For anadmissible given stressfield (a stress field with apossible physical solution),the displacements withineach iteration step areconverging to zero veryfast and stable, whilesimultaneously the arisingstresses converge to thedesired solution.
The URS represents ageneralization of the well-known force densitymethod[2]. Due to itscontinuum-mechanicalbasis, the method isapplicable to both cableand membrane elementswithout any restrictions:e.g. an arbitrary stress
state can be specified for the membrane, whichcan be isotropic in order to generate real minimalsurfaces or orthogonally anisotropic, which isvery helpful for form finding of textile structureswith warp and weft direction. It is even possibleto consistently include pressure forces, which areacting always normal to the surface at everystate of the procedure, in the form findingprocess of pneumatic structures such as air-inflated cushions, etc.
Implementation in Rhino 4.0Rhino Membrane is a fully integrated plug-in forRhino 4.0. The graphical capacities of Rhino 4.0are used as pre- and post-processor in order togenerate the initial geometry and later to displaythe results. Instead of working directly on nurbssurfaces, Rhino Membrane uses the mesh andpolyline objects as geometrical description for theform finding, since “meshes can represent muchmore complex shapes than nurbs surfaces” [3]. In a typical design process, the user models theinitial geometry using a nurbs representation. Inthe next step, the nurbs objects are converted toa polygon meshes (triangles and quadrilateralsare allowed) and input data is assigned to themesh using the interactive menus. When finished,the form finding procedure can be started. Duringthe iterative solution, the intermediate results aredisplayed allowing for checking the convergence.Afterwards, a new mesh object containing thefinal geometry is created. It is even possible tovisualize the resulting stress state.
ExamplesAs Rhino Membrane can work directly withmembrane elements instead of approximatingthose with cable nets, the generation of “real”minimal surfaces is easily possible. >>>pag 14
Modern state of the art application for tensile structure form finding
R H I N O - M E M B R A N E
Figure 1: “Floating meshes” for a hypar-like membrane structure
Figure 2: Iterative form finding of Schek’s minimal surface
Figure 3: Costa’s minimal surface and a cube converged to a sphere
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The shape of the membranes is defined by theinternal equilibrium of the tension stresses anda possibility for reducing the span of themembranes is to introduce beams and arches. In some applications, the membrane is able tostabilize these curved beams or arches.
State of the artIn the past, different applications for stabilizingcompression members by tensioned cables ormembranes have been developed and havebeen used in actual structures. Three differentprinciples can be found in literature: stiffenedarches, the Tensairity system and umbrellastructures. Until now, umbrella structures havenot been used as a permanent structure.
The principle of stiffening arches by means ofbracing cables is approximately 100 years old and was invented by the Russian engineer V.G.Suchov [1]. His basic idea was to reduce thebending stiffness of the arch by preventingdeformation under loads which are not affineto the geometry of the arch (figure 1a & 1b). The reducing of the bending stiffness is equal of the reduction of mass and material andleads to extremely light structures. This structural efficiency was reinvented in the1980’s by Jörg Schlaich [2], adapting the
stabilization of the bicycle wheel for applicationin buildings (figure 2a &2b).
An application of these structural systems in the field of tensile surface structures is theentrance canopy of the “Flower Island” Mainau,Lake Bodensee, constructed in 2002/2003. Thearches have a span of max. 40m and arestabilized by the membrane and bracing cables(figure 3). The diameter of the steel tubes is about 30cm.
Umbrellas can be very efficient: they aredeployable, self anchored, lightweight andintegrated systems. No stay cables oradditional masts are required for tensioning themembrane, only the curved beams. In mostcases, the struts are directly connected to themembrane. This serves a double purpose: onthe one hand the membrane becomestensioned, while on the other hand themembrane stabilizes the struts againstbuckling. Typical for umbrellas is that theycannot be used when snow or high wind speeds
Figure 2a: Principle of bicycle wheelFigure 2b: Museum für Hamburgische Geschichte, 1989 [2]
Figure 3a&b: Entrance Canopy Flower Island Mainau, IF-Partnerschaft Tritthardt und Dr. Ayrle, Reichenau
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>>>pag 13 A very sophisticated example isCosta’s minimal surface, as displayed on the lefthand side of figure 3. A sphere can be generatedout of a cube, by using the cube as startinggeometry for form finding process with isotropicprestress and internal pressure, as shown on theright hand side of figure 3.However, the main application of Rhino Membrane is the design of large-span tensilestructures: as an example, the form finding result of a tensile structure with semi-conical shape isshown in figure 4. For both cones, a linear varyingprestress in meridian direction (right line) isprescribed. In order to guaranty equilibrium, the stresses close to the fixed upper hoops haveto be bigger than the stresses close to the edgecables at the lower part of the structure. The hoop stress is assumed to be constant forthe whole structure.
ConclusionRhino-Membrane is an easy-to-use, yet veryaccurate design tool for form finding of a hugevariety of membrane structures ranging fromsoap film with minimal surface content topneumatic and anisotropically pre-stressedtextile structures. We believe that a modern toollike Rhino-Membrane will help architects andengineers understand the principles behindtensile structure design since there are nobarriers between the user input and the finalresult, like clay in the hands of a sculptor, just afew mouse clicks and the ideas get shaped.
[1] K. U. Bletzinger, E. Ramm, A general finite elementapproach to the form finding of tensile structures bythe updated reference strategy, Int. Journal of spacestructures, 14 (1999) 131-146.[2] H. J. Schek, The force density method for formfinding and computation of general networks,Computer Methods in Applied Mechanics andEngineering, 3 (1974) 115-134.[3] D. Rutten, http://www.reconstructivism.net/
Figure 4: Tensile structure with semi-conical shape
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are expected. It is a well-known fact thatumbrellas can invert under the influence of highwind pressure.
In Tensairity structures, compression and tensionare physically separated. In case of a beam, lowpressure compressed air is used for pretensioningthe tension element and for stabilizing thecompression element against buckling. It can beshown that no buckling problem arises, whichallows the material to be used to its yield limit fortension and compression. As a result, Tensairitygirders can be many times lighter thanconventional beams. This technology is ideallysuited for wide span structures and for deployableapplications such as temporary bridges,scaffoldings or large tents. Prototypes, finiteelement analysis as well as experimental studies have proven the feasibility of the concept(figure 4a & 4b).
New DevelopmentThe Tensairity principle has been applied tomechanical tensioned structures, which has led tothe development of two applications: alightweight column and a wall system for fairstands.
Proposal I: a new lightweight columnBeing lightweight is mostly an attribute of themembranes, while the required compressionelements are often heavy, simple steel tubes. Fordesigning lightweight masts two possibilities areoften used: truss structures or Vierendeel girders,which reduce weight but increase labour hours.Another possibility is to use high strengthcomposite materials in which case themembranes and cables need to be appropriatelyconnected to the mast, and the mast, in turn, tothe foundation.
In this project the first proposal is a mast made ofmassive bars with a rectangular or round crosssection. The bars are connected to a plate at thebottom and the top. In the centre of the plate is acable which can be tensioned. By tensioning the central cable, the bars becomecurved and are protected against buckling by amembrane which covers the whole system. In the first design the bars are guided in pocketsconnected to the membrane. The advantage isthat the mast can be brought to the site in itsrespective parts, be assembled and becometensioned on site (figure 5).
The problems which have to be solved are:defining the buckling load of the mast in relationto the number of bars, the cross section of bars,the length of the mast, the tensioned geometry,the tension force, the stiffness of the fabric andthe orientation of the yarns.
Proposal II: New wall and roof structureThe second proposal uses the same principle, butreversed. Starting with a cylindrical membraneand a space truss, the free edges of the truss arepulled outside, thus tensioning the membrane andstabilizing the bars (figure 6).
In case these structures would be used for a fairstand, further investigations need to be carriedout, especially regarding the definition of an
opening for the entrancewithout destroying thestructural integrity. Theflexibility or stiffness of thebended bars has to beexamined in terms ofexternal load bearingbehaviour and thecapability of bendingwithout too much increaseof bending moments. The results of the simulation return the elasticstiffness and ultimate stress for the bars. Thetension stress in the membrane has to becalculated in relation to the bending stiffness andstability of the bars. For the roof - built in themanner of umbrellas - the same tasks have tosolved, such as defining the bending stiffness ofthe bars in relation to the tension stresses,external load, buckling behaviour and stabilityoffered by the membrane.
1990, figure 1b see page 42, Abb.65[2] Schlaich, Bergermann und Partner, Transparente Netztragwerke, Stahl und Form, Stahl-Informations-Zentrum
Düsseldorf, 1992, figure 2b see page 13[3] M. Pedretti, Tensairity, ECCOMAS 04, Jyvaskyla, Finnland, figure 4a see figure 1, figure 4b see page 5
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The Dalian seals show hall is located near to the estuary of the Dragon Riverin Lushun port of Dalian, China. You could enjoy the beautiful view of the river and the ocean at the same time. The client engaged us to make the design being a new landmark, being a good building to let the spectatorsfeel comfortable to enjoy the show. In addition the structure must befinished in the spring of 2009, which means we have to finish all thebuildings in short time.
So we put forward the following three points to be achieved. The 1st point isthe magnificent sight; the 2nd is to have the good architectural functioningfor a seals show, such as good internal environment, pure natural sun lightand energy saving. The last point is to try to finish the roof in a very shorttimeframe. All this is a challenge to the design team; fortunately weproposed a wonderful membrane structure. After more than 10 conceptualdesign adjustments, the client’s architect approved the concept (figure 1).
The building is the 1st specialized space for a sea dog’s show in Dalian. Theroof system is a hybrid structure consisting of long span truss beams,
suspension cables, edge cables and membrane. The grandstands arereinforced concrete frames. They have a total area of 3000m² and can hold 1000 spectators.
The roof system is a complicated space system which consists of a 76m spanmain truss, 10 secondary truss beams and 2 arched trusses at the entries. The cover materials are PVC-polyester membrane and glazing. Most of thesteel structure components are placed on the top of the concrete columnsexcept the two arched truss es, which are positioned on the ground. Thetotal steel structure has a width of 70m, a span of 76m, and the height is25.8m.
The membrane is tensioned between adjacent secondary truss beams;creating anti-clastic curved surfaces. A water-proof membrane will cover the connection area. A PVDF coated fabric type 3 FR 1000 made by Mehler in Germany is used.
We use the Chinese program 3D3S to do the form-finding, nonlinearanalysis, Chinese standard of steel & membrane structure checking and
Context of the design When the Hogeschool Gent wrotedown the task for the constructionof an Open Learning Centre, thedesign team stated from thebeginning that this had to be morethen a new solitary building blockon the campus Schoonmeersen. Inthe tradition of the seventies thiscampus was composed by severaldetached buildings that had beenbuilt around a football field and aparking. By the implantation, theconcept of the Open LearningCentre and its program (a library of2500m² with study rooms forprofessors and students, an
auditorium with 330 places and anew student restaurant) it was forthe first time that the architectssearched for a link between thedetached buildings.
The idea of the Open LearningCentre is in fact to be “open” for allstudents of the campus and morewidely for the complete Hoge schoolGent! To support and reinforce theexisting structural elements of thecampus the building was located onthe most important pedestriancirculation axes to fully fulfill itscentral function. The “final touch” of this intervention is theconstruction of a covered street.
Place of the steel elementsThe Open Learning Centre iscomposed by two main buildingblocks which are linked by 3 circulation volumes. Between both buildings an outsidespace, which acts as informalmeeting place for the students, issituated. This outside space iscovered with a canopy, made from
PVC-coated polyester fabric on aslender steel structure.
The canopy fulfills at the same timeseveral requirements: it offersprotection against rain, issufficiently light-transmitting sodaylight can penetrate into thebuilding and acts as a sunprotection for the entirely glazedlibrary.
OPEN LEARNING
CENTRE GENT, BELGIUM
THE DESIGN OF DALIAN SEALS SHOW HALL
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Figure 1. General presentation of the building
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patterning. The form-finding is done with anonlinear finite elementmethod. After the form-finding, the membranesare initial equilibriumand minimal surfaces.We put the entirestructure together toperform the non-linearanalysis. The beam elements, the cable elements and the membrane surfaceelements are in one computer model, so it is easier to get a more accurateanalysis report.
The load cases: 1. Pre-stress (PL): 2.0 x 2.0kN/m for membrane; 20kN & 40kN for edge cables;2. Dead load (DL):0.1 kN/m2;3. Snow Load (SL): 0.4 kN/m2;4. Wind Load (WL): 0.65 kN/m2;5. Seismic Load: Chinese Standard, the first vibration mode is 0.24433s;6. Temperature Load: ±30ºC.
The whole design including thepreliminary design, analysis andmaking the shop drawings took usabout two months. Now, the steelstructure is installed on site. Parts ofthe membranes are being mounted(Figure 2).
Name of the project: Dalian Seals Show HallLocation address: Lushun port of Dalian, ChinaClient: Dalian YiHai Travel CorporationYear of Construction: 2008General engineering, detailing and shop drawing: Beijing Space frame
Consulting Engineers Co., Ltd. (SFC, China)Engineer for the steel structure: Zhao Yu, Xiang YangEngineer for the membrane: Zhao YuSteel & Membrane manufacturing: YF Space Membrane Technology
Engineering Co. Ltd (China)Installation: YF Space Membrane Technology Engineering Co. Ltd (China)Material: PVDF-coated fabric, type 3 FR 1000 by Mehler, GermanyCovered surface: 3000m2
Construction and concept of the coveringThe canopy is a mixed steel/membrane construction whichwas designed strictly modular. It contains 28 fields (4.80m wideand approximately 14m long)supported by 29 main arches placedbetween the building blocks. Eachmembrane field is tensionedbetween 2 parallel arches and twoboundary cables. On the mainarches transverse secondary archesare placed with a height of 0.75mfor a span length of 4.80m. Thecoated fabric is stretched over thesecondary arches in the appropriatesaddle form. The initial prestressamounts 3kN/m.
The main arches have been tiltedand the secondary arches followthis inclination to be able totransfer the pretension to the mainhead arches in an optimal way.
The pretension is mainly taken inthe steel construction itself: themain arches and the secondaryarches form a rigid framework. The weight of the membraneconstruction is transferred by steelcolumns to the concrete structureof the building.
The choice of using steel and fabricfor the covering was madeconsciously taking into accounttechnical as well as aestheticconsiderations. The combination ofthe specific characteristics of bothsteel and fabric made it possible toobtain a light, aerial and financiallyfeasible solution.
Calculation basesTo assure sufficient stability against horizontal deformations, theconnections of the long steel columns to the foundationwere considered as bending stiff, whereas the short columnswere considered as partially bendingstiff. The connection between the
columns and the main arches areconsidered as pin connections. Toobtain sufficient stiffness in the roofconstruction, the necessary windbracing and ties were added. Themost important loads for thisproject are the wind loads.
Name of the project: Open Learning Center Location address: Gent, BelgiumClient: Hogeschool GentFunction of building: Library, study rooms, auditorium
and student restaurantYear of construction: 2008Architects: baro cv, Sum Project Engineers: Fraeye Herman Ingenieursbureau NVConsulting engineer for the membrane: Marijke Mollaert
Vrije Universiteit BrusselContractor for the steel construction: Staalconstructies RietveldSupplier of the membrane material: Mehler Tex.nologiesManufacture and installation of the tensile membrane: Axel Troch bvbaMaterial: PVC-coated polyester, Valmex FR 1000 MEHATOP F - type IIICovered surface (roofed area): 1880m2
Figure 2: Installation of the membrane
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The Brampton Civic Hospital wasopened in 2007, providing healthcareservice to over 400.000 residencesin Brampton and the surroundingareas. The new hospital, part of theWilliam Osler Health Centre, is apublic-private partnership involving ajoint venture between Ellis DonCorporation and Carillion CanadaInc.
The new hospital required a series ofprotective canopies to define andenhance the main access points.Soper’s provided a total of sevenengineered tensile membranecanopies, all manufactured of PTFESheerfill V fabric as well asarchitectural grade columns andstainless steel cables and fittings.Columns are all painted with 2-partepoxy paint for tough, UV-resistantdurability.
Main Entrance Canopy: The mainentrance canopy wraps around thefront entrance of the hospital,boasting a signature showpiece tothe outside world. Altogether, the 3-sided canopy measures over 60min length. (Figure 1)
Radial Drop-off Canopy: Thisangulated radial-shaped canopyprotects patients and visitors at thedrop-off area beside the mainentrance. This canopy, 90m inlength, attaches to the mainentrance canopy to provide aseamless transition along the front of the hospital. (Figure 2)
In-Patient Entrance Canopies: Twocanopies, each measuring 6m x 12m,were installed at the in-patient
entrances on the north side of the building. (Figure 3)
Pond Lookout: A hypar-shapedcanopy was installed in a reflectiverest area overlooking a pond. Its“natural” shape adds to thetherapeutic nature of this rest area.(Figure 4)
Rooftop Canopy: A small canopywas installed on the rooftop abovethe parking garage to provide addedshelter to employees of the hospital.
Bus Shelter Canopy: Anothercanopy, measuring 6m x 12m, wasinstalled at the bus shelter toprovide additional protection to staffand visitors coming to the hospitalvia public transit.
The biggest challenge wasovercoming the intricacies of
interfacing and staging the tensioncanopies with the new buildingconstruction schedule. Soper’s wasable to deliver its product whileworking within specific timeframesand constraints.The canopies, designed to have a 30-year life expectancy, have beenwell received by all those involvedand also the people (patients, staff,and visitors) who frequent thehospital. Soper’s is proud to havebeen a player in a local project ofsuch scope and hopes to replicate itssuccess at other hospitals andmedical centres across NorthAmerica.
Name of the project: Canopies for the Brampton Civic HospitalLocation address: Brampton, Ontario, CanadaClient: William Osler Health CentreFunction of building: Series of protective canopies Year of construction: 2007Architects: Adamson Associates ArchitectsEngineers: MMM GroupMain contractor: Ellis Don Corporation & Carillion Canada IncDesign, engineering and manufacture membrane: Soper’s Engineering
Fabric Solutions Material of the membrane: glass-PTFE Sheerfill V fabric
Canopies for the Brampton Civic Hospital WILLIAM OSLER HEALTH CENTRE, BRAMPTON, ONTARIO
Figure 1. Main entrance Canopy
Figure 2a. Drop-off Canopy
Figure 2b Drop-off Canopy
Figure 3. In-Patient Entrance Canopy
Figure 4. Pond Lookout
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IntroductionTextile roofs need periodical inspection and maintenance that often implyre-tensioning, cleaning or replacing. Accessibility for maintenance and repairis therefore a way to get these tasks done.
In Rubí (32 km2, 70.000 inhabitants, 20 km from Barcelona), the City Councilwanted to roof their 40m × 20m open air sport ground transforming it intoa pavilion. Easiness of maintenance and accessibility were emphasized asmain requirements, provided that they had to be in charge of a non-specialized municipal crew.
Steel structureIn order to consider these requirements, a textile roof supported by a tubularsteel structure was designed. The structure is based on a series of four selfsupported frames, placed every 10m and composed by 4 arches leaning on 8 pillars.
Every arch is designed as a catwalk by means of 6 CHS Ø 50.3 braced withlattice girders Ø 30.2mm. The cross section is U shaped forming a 60cmwide catwalk protected by two railings. It results on a double triangularsection stable without bracing and accessible for installation andmaintenance.
The 8 columns are also latticed and made ofCHS, 60cm × 80cm in plan. Their dimensionsin plan allow for stability. The result is adiaphanous space, not interrupted bydiagonals or ties. Fewer impediments procureclearness and flexibility. The columns are lined with perforated curvedplates for safety and to proportion volume in the aim of delimiting the space of theenclosure in a discontinuous non obstructive way.
Purlins between frames are not needed because the fabric is structural.(Purlins may account up to 40-50% of the total cost of the steel in a singlestorey frame building).
A ridge-beam on top and edge-beams at each side complete the structure toreceive end stretch the membrane. The edge beams are cantilevered 5m atthe ends to reach the 40m of total length.
MembraneThe roof is PVC-coated polyester fabric resting on the ridge-beam andstretched against the arches and edge-beams by means of elastic rope. Itprovides translucency, natural diffused light and structural lightness.
Double curvature is obtained by the arches, (the lower chord is a 14m radiusarch) and the 1m downwards sag in the longitudinal direction, (roughly a10% of the distance between arches). Proper drainage is improvedpreventing flatness on top with a horizontal ridge-beam. The edge latticedbeams at each side receive the membrane avoiding the diminishmentscaused by curved edges and allowing for vertical enclosures.
InstallationThe installation of the membrane wasconsiderably facilitated by the arches used asfootbridges. The figures illustrate the wholeprocess.
Name of the project: Municipal sport pavilion in Rubí Location address: Rubi, Barcelona, SpainClient: Rubí City CouncilYear of construction: 1987Architects: Llorens & SoldevilaManufacture and installation: Arquitectura Textil
(www.arquitecturatextil.com), Montmeló, SpainMaterial membrane: PVC-coated polyesterCovered surface: 40m x 25m
Figure 1. General view
“MUNICIPAL SPORT PAVILION, RUBÍ, SPAIN”DESIGNING FOR EASY MAINTENANCE
Figure 6. Latticed edge-beam and
catwalk
Figure 7. The arch is designed
as a catwalk
Figure 8. The columns are lined withperforated curved plates
Figure 9. Rectilinear edge beams avoiddiminishments caused by curved edges
Figure 10. Latticed edge-beams arecantilevered 5m
Figure 2. Plan. A ridge-beam on top prevents flatness
Figure 3. Lateral elevation.
Cross bracing is avoided
Figure 4. Frame elevation
Figure 5. The frames are self supporting
Figure 11. Installation process
TECHTEXTIL 10TH STUDENT COMPETITION 2009TEXTILE STRUCTURES FOR NEW BUILDING30 JANUARY 2009 CLOSING DATE FOR RECEIPT OF ENTRIES
The international association TensiNet and Techtextil – InternationalTrade Fair for Technical Textiles and Nonwovens are holding the 10th
Student Competition on 'Textile Structures for New Building.'We cordially invite all students of architecture and building engineering,product design, or any other relevant subjects, to apply. We also herebyinvite all new entrants to their professions who are practising thesesubjects, providing they took their degree after 1 January 2008. Forpurposes of identification please enclose a copy of your student identitycard or degree certificate respectively with your registration documents.
This competition is designed toidentify innovative thinking andinnovative solutions to problems,featuring construction projectscapable of concrete realisationwhich use textiles or textile-reinforced materials. A further aimis to encourage students and newentrants to the professions. Thecompetition is further intended to
strengthen contacts between the younger generation, the universities,the technical-textiles industry and broad sections of the buildingindustry.The competition will be run under the professional and technicalsupervision of Werner Sobek, Professor of Engineering at the Institute ofLight Construction Design and Building (ILEK), University of Stuttgart.
Scope of competition
The competition covers all areas of textile building:• Earth-moving, road building, landscaping, environmental protection• Civil and industrial engineering• Structural engineering – from construction using textile-reinforced
concrete or plastics to construction using membranes for permanentand temporary, adaptable and mobile buildings
• Interior construction – including such developments as the use ofpolymer fibre-optic cables for light transmission, textile air-channelsystems for draught-free air conditioning in rooms, movable soundinsulation walls in production facilities, etc.
• Product design for architecture.An additional focal theme has also been included: 'Suitability for re-use and recycling'.The subject of the project submitted is a free choice. Work will be accepted, which has been produced either under asupervisor or without a supervisor.
Jury
The international jury judging the 'Textile Structures for New Building'competition will include well known representatives from the universities,eminent architects (textile building) and engineers. A representative ofTensiNet will serve on the jury on behalf of the organizers. The chairmanof the jury will be Professor Werner Sobek. The jury’s decision will be finaland incontrovertible. Individual reasons for refusal of a proposedsubmission cannot be given, for organizational reasons.
Prizes and categories
TensiNet will be providing thecompetition prize money of € 8 000.00
The jury will award prizes in thefollowing categories:• Macro-architecture• Micro-architecture• Environment and ecology• Composites and hybrid structures
The prize money will be divided asfollows:First Prize: € 1 250.00 per categorySecond Prize: € 500.00 per categoryThird Prize: € 250.00 per category
Prizes will be awarded at Techtextil inFrankfurt am Main on 15 June 2009.The award of a prize will beconfirmed by a certificate. Prize-winning projects will also beexhibited in a special show duringTechtextil from 16 - 18 June 2009.The organizers reserve the right toexhibit projects at other Techtextilevents. The organizers will furtherinform both the professional world and the public about all prize-winning projects.
More information on www.tensinet.com/content/view/73/54/
Special Mention in the Micro ArchitectureCategory, Jesús Flores Hernández, 2007
TENSILE STRUCTURES Arq. Roberto Santomauro
T E N S O E S T R U C T U R A SDESDE/FROM URUGUAY
Author: Arq. Roberto Santomauro Language: Spanish and English
Size: 25x25cm, 128 pages full colourEditor: Arq. Eduardo Folle Chavannes
Grafic design and Digital imaging: Rodolfo Fuentes Baez Prefaces: Nicholas Goldsmith, FAIA, New York, USA.
Juan Monjo Carrió, Madrid, SPAIN. Bruce Wright, USA.
This book is available since the end of September and will be presented on the next 3th Latin AmericanSymposium on Tensile Structures in October 2008 (Acapulco, Mexico).
