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AKELLER insight // 2017

insightBuilding on our strengths

2017

2KELLER insight // 2017 KELLER insight // 20171

In this issue

Projects

S36 – section Unzmarkt .................................................................................. PAGE 3

U3A University library Graz ............................................................................. PAGE 5

Baufreund Schladming .................................................................................... PAGE 6

A11 Karawanken tunnel ................................................................................... PAGE 7

Rüdengasse Vienna ......................................................................................... PAGE 9

Hörbigergründe Vienna ................................................................................... PAGE 11

Altgasse Bregenz .............................................................................................. PAGE 12

Power plant GKI – Ovella ................................................................................. PAGE 13

Waldhof Großarl................................................................................................. PAGE 15

Power plant Gries .............................................................................................. PAGE 17

Grandhotel Titlis, Engelberg CH .................................................................... PAGE 19

Flood protection Rhône, CH .......................................................................... PAGE 21

Visionary Prague, CZ ....................................................................................... PAGE 23

Južne Mesto, Bratislava SK ............................................................................. PAGE 25

Machine construction company Volgger, South Tyrol IT ........................ PAGE 26

Metro Palermo, IT ............................................................................................. PAGE 27

Follo Line, Oslo NO ........................................................................................... PAGE 29

INNNES warehouse, Reykjavik ISL ................................................................ PAGE 31

Company news

20 years Keller Fondazioni in Italy .................................................................. PAGE 33

Keller Geotehnica – 10 years on the Romanian market.......................... PAGE 35

Research project Unteres Hausfeld, Vienna .............................................. PAGE 37

New logistics hub in Söding ............................................................................ PAGE 39

Kindergarten Hausmannstätten visits Keller ............................................. PAGE 40

BIM – Keller is ready .......................................................................................... PAGE 41

‘ANYONE WHO STOPS IMPROVING, HAS STOPPED BEING GOOD.’

I like this quote from Robert Bosch very much, as it says exactly what I’m convinced of in a few words – you can only exist by continous improvement. Improvement also takes change, and you have to be open to that.

In the last few years we have gone through many changes, we have ofered new products, have entered new markets, some oices have changed their location and our corporate design has been refreshed. In this spirit, we also wanted to redesign and improve our magazine. What stayed are the great project reports to provide you Insight into our daily work – what changed is the look and the name. Another change you are holding in your hands, the irst English issue. So I kindly ask you to take some time to have a look into our world, get to know our projects and the people behind them because every inished project includes a part of our employees and every site is very special to us. We are proud to build the future together with you.

Best wishesAndreas Körbler

EDIT

ORIAL

CONTENTS EDITORIAL

Masthead:Keller Insight is a magazine by Keller Grundbau Ges.mbH and ailiated companies.

Owned and published by:Keller Grundbau Ges.mbH, Guglgasse 15 / BT 4a / 3.OG, 1110 ViennaE-Mail: [email protected]: Amela Müllner-AvdicProof-reading: Rob MadillDesign, layout and print: G.A. Service GmbH, Siezenheimer Strafle 39, 5020 SalzburgPlease send ideas and suggestions to the publisher. All rights and modiications reserved.

3 4KELLER insight // 2017 KELLER insight // 2017

PROJECTSPROJECTS

S36

S36

S36

B317

B96

ST.GEORGEN

OB JUDENBURG

Judenburg

Edling

Mur

Mur

junctions

St. Georgen

tunnel

St.Georgen

(approx. 610m)

anchor wall SM 3

+ 3a + 3b

anchor wall SM 4

anchor wall SM 8

bridge M 54

Gstattbauer

anchor wall SM 11 + SM 12

junction

Unzmarkt

anchor wall SM 26

bridge M62+63

tunnel Unzmarkt

(approx. 950m)

UNZMARKT

retaining wall SM 14a

rerouting of the Mur river

tunnel

Scheilinger Ofen

Murau

SCHEIFLING

Friesach

I n the 2014 issue of this magazine we reported about Phase 2, where we supported the bypass route for St. Georgen ob Judenburg with bored piles. Following our good performance then, the client awarded

us the foundation and support works for the Unzmarkt tunnel, which is approximately 950m long and represents the centrepiece of the section. The foundation for two bridges and the tunnel itself was accomplished by

using bored piles of 90cm diameter. The support works for eight slopes consist of anchored shotcrete retaining walls.

FOUNDATION WORKSThe installation of bored piles for the foundation of the bridge M62, M63, which crosses the existing railway route, started in March 2017. Due to the geological and hydrogeological conditions, the 90cm piles were bored with water load, to prevent a lifting of the foundation base. The works for the 950m long tunnel continued at the end of May, after an interruption caused by the construction worklow. Here, three spaced pile rows with lengths between 9.6 and 22.6m were installed with the Kelly method in a gravel dominated subsoil which shows rock layers in some areas. Two rotary drilling units (a BG 28 and a BG 30) have been used to install the 1,806 piles, with a total length of about 28,300m, on schedule.

Special attention has to be paid to the co-ordination of the two rigs. Due to construction worklows and phases (mainly the repeated rerouting of the busy main road), a relocation of the drilling rigs from one section to another has to be planned diligently.

The completion of the foundation works for the tunnel is scheduled for spring 2018. Subsequent to those main works, the foundations for the wildlife overpass Gstattbauer and the retaining wall SM14 A have to be completed as well.

SUPPORT WORKS The support works started at the end of March with the construction of the anchor wall SM 12. That retaining wall is approximately 216m long and at its peak is around 9.3m high. The wall consists of approximately 1,600m² shotcrete with 196 permanent anchors. According to the geotechnical speciications, in a irst step the wet shotcrete was installed and nailed. Afterwards, the permanent strand anchors were drilled. For the geotechnical monitoring, 19 load cells and two inclinometers were installed as well as reference marks made to enable the detection of deformations.

The biggest challenge during the anchor installation was the extremely high water inlux in some areas, which was reduced signiicantly by the installation of packers. Despite the diicult geological conditions with partly very abrasive rock, the retaining wall was inished as planned. Once it was completed, we started the execution of the retaining wall SM 11, located directly underneath, with a shotcrete surface of approximately 2,000m² and 254 permanent anchors.

Thanks to detailed worklow planning and comprehensive co-ordination with the other trades on site, the works are running on schedule.

CONTINUATION OF A SUCCESS STORY

Next phase of the S36 Murtal expressway

The S36 Murtal expressway is currently undergoing a reconstruction due to inish by autumn 2020. Some parts are new and in some areas the existing main road is being upgraded into an expressway. Phase 2 spans a length of approximately 5.6km between St. Georgen ob Judenburg and Scheiling through the idyllic Murtal (valley of the river Mur). Once this section is inished, the traic in the severely afected municipalities of St. Georgen and Unzmarkt will be signiicantly reduced.

PROJECT INFORMATION

Investor: ASFINAG Bau Management GmbHCustomer: Massivbau Ges.m.b.H.Geotechnical consultant: GDP Zt GmbHQuantities:

» 32,000m piles » 15,500m permanent anchors » 5,700m² shotcrete

Execution period: March 2017 - November 2018

Dominik Binder Keller Grundbau

Söding

AUSTRIAUnzmarkt

under construction

junction

adaption of existing routes

in planning phase

Scope of our works


PROJECTSPROJECTS

T he history of Graz University library goes back to the 16th century. When the Jesuit college, next to Graz Cathedral (today known as the Old University ), was conirmed as the Jesuit university in

1585, their library got the status of a university library. During its history, the library stock increased so much, that in 1891 a new building was erected at today’s location and was inaugurated in 1895. The most prominent additions were the extensions in 1950 and 1970, as well as the annex in 1995 by architect Günther Domenig, part of the new construction of the RESOWI centre.

As the more than 10,000m² building does not meet the up-to-date requirements for a library, a restructuring, extension and modernisation programme was planned. A competition was held to design a modern library centre surrounding the listed reading hall, while accentuating the former historic façade. The winning design, by Atelier Thomas Pucher ZT, features a two-storey glass cuboid which hovers above the reading hall. The 1970 extension will be demolished to reveal the façade of 1895. This, in turn, reveals a big forecourt which is “roofed” by the glass cuboid. The southern extension of 1950 will accommodate a lecture hall for more than 400 students, the book archive as well as the administrative oices. The Domenig annex will stay. A light-looded atrium connects the library with the main university and serves as access to the lecture hall.

The technical centre is located below the atrium. Therefore, it was necessary to underpin the existing building. Taking the historic building structure into account (the listed reading hall is located in the library) Soilcrete® jet grouting was chosen for the works, as it is known to be a very gentle method.

Largely, the subsoil consists of three layers. An approximately 4m thick top layer of ine-sandy silts is followed by sandy gravel with changing silt proportion up to a depth of 8m below surface. That gravel layer is also the foundation level of the historic buildings. Natural ground water is found around 5m below surface and is therefore located more or less on the same level of the general excavation for the new building, but can, at the most, rise only to the foundation of the existing structure. The ground engineering design took the highest ground water level into account. The

works did not include the construction of a sealed pit, but a possible open residual dewatering should be enabled besides the static requirements.

Some parts of the technical centre are up to 7m below surface and so they are located below ground water level. In these parts, the Soilcrete® elements were executed to the Neogene, the natural aquifuge, which led to a signiicant reduction of the residual dewatering. Local bracings completed the pit support.

The works were carried out from the beginning of May until mid-June and met the time schedule of the investor. As the Austrian site personnel were busy elsewhere, our Finnish colleagues completed the site to the full satisfaction of the customer. Having international backing enables us to meet our customers’ needs with the usual quality, in spite of capacity constraints in our own Business Unit.

NEW CHAPTER FOR STYRIA’S BIGGEST

LIBRARY Modernisation of the U3A university library in Graz

One of the biggest infrastructure projects at Graz University is currently being carried out on the Karl-Franzens campus. The university library, the biggest in Styria with up to 4 million pieces of information, is undergoing a major refurbishment.

PROJECT INFORMATION:

Investor: BIG Bundesimmobiliengesellschaft mbHCustomer: Strabag AG – Direktion AC Hoch- und Verkehrswegebau Knt/StmkQuantities:

» 1.400m³ Soilcrete® elementsExecution period: May – June 2017

I In the course of extending the Baufreund hardware store in Schladming, a new warehouse was built. The new building is located north of the existing store and south of the main road B320. The construction site

itself is on a slope and the new building was embedded into the ground on the northern side.

Keller was awarded the slope stabilisation works, which consisted of a 20cm strong shotcrete lining and anchoring with injection bolts in a grid of 1.5 x 1.5m (length from 10 to 12m).

The soil in the construction area consisted of quaternary meadow sediments poured by the river Enns, which are underlain by unconsolidated debris. The washed out meadow sand and gravel are permeable and widely stable. The soil conditions together with the relatively tight time schedule of four weeks and, particularly the temperatures during the execution period from mid-November to mid-December, challenged the project team. To be able to inish the project in time, the wet grouting shotcrete method with a shotcrete manipulator was chosen. Therefore, we were able to execute a daily output of 80 to 100m² shotcrete lining including the related anchoring of approximately 400m injection bolts. In contrast to the dry-mix shotcrete method (dry mix incl. accelerator, compressed air and silo) which we used to apply, for the wet method the shotcrete was delivered to site with truck mixers, put into a concrete pump and then pumped to the shotcrete manipulator. On the nozzle, the accelerator is then added and grouted to the wall by using compressed air. Due to the low temperatures, the inished areas had to be covered and heated beneath daily to avoid any inluence on the shotcrete setting behaviour.

The 80m long and ca. 16m high L-shaped shotcrete wall was split into two parts. The irst one was the upper part which served as permanent stabilisation above the new warehouse. As the main road B320 was pretty close, the used shotcrete needed to be resistant to anti-frost-salt. Furthermore, all bolt heads were grouted with the shotcrete as future corrosion protection. The second part didn’t require any special shotcrete quality as it was covered again after the construction of the new building.

Thanks to excellent collaboration between all those involved, the works were inished on time to the full satisfaction of the customer.

Roman WeidacherKeller Grundbau

Söding

SHOTCRETE BRAVES ICY TEMPERATURES Slope stabilisation for a hardware store

Irrgeher ClausKeller Grundbau

Söding

AUSTRIAGraz

AUSTRIASchladming

PROJECT INFORMATION

Investor: Landesgenossenschaft Ennstal Customer: Landesgenossenschaft Ennstal Consultant: INSITU Geotechnik ZT GmbHQuantities:

» ca. 1,230m² shotcrete, d = 20cm, reinforced in one layer » ca. 550 injection bolts, 10-12m

Execution period: November – December 2016 (4 weeks)


PROJECTSPROJECTS

K eller Grundbau was awarded the ground engineering works in the portal entrance area. These consist mainly of the foundations for a 300m long two-lane motorway bridge, the construction of a

500m long and 12m high retaining wall anchored in several strata which is necessary for the expansion of the road and the re-anchoring of several existing retaining walls.

MOTORWAY BRIDGE KA15.3

The foundation of the pillars was originally designed by caissons or 33m deep bored piles. In the course of the caisson execution, the soil conditions showed to be diferent than stated in the soil report. During drilling, in particular, it became clear that continuous chiselling was necessary and at the same time the groundwater encroached intensively, so that the investor stopped the execution at the irst pile. Therefore, we were asked to design an alternative foundation.

Our solution consisted of drilled micropiles and was agreed with the designer and the structural engineer. The required pile lengths were the

same at 33m, but instead of nine bored piles per pillar, 20 micropiles were now necessary. We used piles SAS 670/800 with a nominal diameter of 63.5mm and double corrosion protection. They were installed in ten shifts as scheduled.

RETAINING WALL KA15.4

This retaining wall had to be constructed to widen the existing motorway, which is located in a steep slope, by two further lanes. The wall had to be executed bottom-up and not top-down as usual.As a irst step, the slope was cut and 15 elliptic wells with depths to 21m were drilled. The foundations of the retaining wall was put onto those wells and afterwards was anchored with permanent strand anchors. Then, the bottom of the wall was concreted and backilled up to an exactly deined level. That concreted part was again anchored with a stratum of strand anchors. The starting points for drilling, therefore, were located more than 3m above the working platform in some areas. Once the anchors were tensioned, this section was allowed to be backilled up to the level of the preliminary concrete top edge.

As a raising of the working platform on the outside of the retaining wall was not possible due to the steep slope, the working sequence had to be adapted. On the hillside of the already concreted wall, the working platform was raised to the level of the fourth and upmost anchor horizon. The 9-strands permanent anchors were then drilled with casing to a depth of 60m. The tension elements were installed and the annulus between borehole wall and ribbed sheathing was grouted with suspension, whereas the inside of the sheathing was not grouted at that time. Immediately after pulling out the casing, the anchor strands were pulled out from the ribbed sheathing to the required length (10 to 12m) up to the later outer edge of the retaining wall and were coiled. Only afterwards were the permanent anchors illed inside and post grouted.After completion of the upmost anchor stratum, the drilling platform was lowered to the designed third anchor horizon and the anchors installed analogously to the fourth anchor stratum. Then the retaining wall was concreted up to the designed top edge, but not backilled.The procedure of backilling the retaining wall above the second anchor horizon starting from the bottom had to happen in the following steps in order to guarantee a balance between earth pressure and pre-stressing force:

GET ALONG SAFELY, BUT IN A SHORTER TIME

Preparatory works in the portal area of the Karawanken tunnel

(motorway A11)

The tunnel through the Karawanken Mountains on the border between Austria and Slovenia is 7.9km long and is being expanded by the end of 2023. The irst step is the construction of a second tunnel tube which will avoid oncoming traic and therefore will increase safety signiicantly. Furthermore, the extension will relieve the bottleneck on the way to the South and back, what will consign the repeated traic jams to history.

PROJECT INFORMATION

Investor: Asinag Bau Management GmbHCustomer: Massiv Bau GmbHDesign: GDP ZT GmbH and ZT Lorenz Quantities:

» 1,300m micropiles (load capacity 2,500kN), lengths up to 33m

» 7,000m permanent strand anchors (load capacity 2,100kN), lengths up to 60m

Execution period: September 2016 – May 2017

Herbert SieglKeller Grundbau

Söding

KELLER insight // 2017 KELLER insight // 2017

AUSTRIAKarawankentunnel

17

9

432

6

8

5

16

13

14

17

121110

1. Backill up to the level of the duct for the third anchor stratum and compaction.

2. Excavation of a trench in anchor axis to the retaining wall.3. Putting the anchor strands into the trench and thread them through the

intended recesses. 4. Producing the double corrosion protection in that open section.5. Assembling the anchor head and pre-stressing to 100kN.6. Filling the trench with lean concrete to protect the anchor.7. Further backill the retaining wall to a statically given level.8. Stressing the anchors in the third horizon to inal force.9. Backill and compaction up to the duct level of the fourth anchor stratum.10. Excavation of a trench in the anchor axis to the retaining wall.11. Putting the anchor strands into the trench and threading them through

the recesses in the retaining wall. 12. Producing the double corrosion protection in that open section.13. Assembling the anchor head and pre-stressing to 100 kN.14. Filling the trench with lean concrete to protect the anchor.15. Backill and compaction to a new statically given level.16. Stressing the anchors in the fourth horizon to inal force.17. Backill and compaction up to the designed level of the future road.RENOVATION OF THE EXISTING RETAINING WALLS

In the course of structural safety inspections on the existing retaining walls, it was established that the existing construction did not show the required stability and it can’t be proven respectively. New permanent strand anchors with lengths up to 40m and load capacities of 2,100kN were installed as strengthening measures. The existing now non-functional strand anchors were left in the soil as reserve after the renovation.


PROJECTSPROJECTS

COMPLETE SOLUTION FROM ONE SOURCE

Pit support in the heart of Vienna

In Rüdengasse in Vienna’s third district, on an area of 2,700 m² a new housing complex is being built. The two-loor basement design required a pit support. Keller Grundbau acted as main contractor and designed and built a technically and economically sophisticated solution.

KELLER insight // 2017 KELLER insight // 2017

Jakob Pelzl Keller Grundbau

Vienna

AUSTRIAVienna

T he construction area was surrounded by three streets and a six-loor building. In order to respect the property limits, Keller Grundbau designed and installed the pit support with Front-of-

Wall (FoW) piles. By using the FoW method, the piles could be bored along the existing neighbouring building and provide a space-saving and eicient pit support. By using this cased technology, the existing brickwork of the former building could also be cut without diiculties. The piles, which were 52cm in diameter, could also take the vertical loads of the new construction and thus will form an essential part of the inished building.

To meet the high requirements of position accuracy of the piles, they were staked out prior to drilling by using ixed points and a total station, so that the deviations were less than the allowed standard tolerances. The piles were anchored in up to two diferent strata under public land and below the existing buildings. To avoid issues with anchoring into adjacent owners’ land, we used removable anchors, which means that the steel strands can be pulled out once they are not needed.

The pit needed to be excavated up to 8.7m below pavement level. Taking into consideration that the groundwater was approximately 4m higher than the inal level of excavation, the gaps between the piles were sealed with Soilcrete® jet grouting. The Soilcrete® columns embed into a silty-clayey layer, which itself sealed the slab naturally.

Once the pit was sealed from all sides, the lowering of the groundwater could start. For dewatering, four wells with a ilter pipe diameter of 20 cm were drilled all over the construction site and each equipped with a submersible pump. The upcoming water was led through a specially manufactured desanding plant and then fed into the public sewer. The water level outside of the pit was measured by using a control gauge and was compared with the assumptions from the static calculation. After the groundwater

inside the pit was lowered, the excavation up to the contractually agreed depth took place and, inally, the inished pit was handed over to the JV for structural engineering by Dywidag and Swietelsky.All works, consisting not only of the execution of the pit support, earthworks and dewatering, but also the necessary oicial administration work and iling of submissions, were inished to the full satisfaction of the customer.

KELLER insight // 2017

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PROJECT INFORMATION

Investor / customer: Aliqua Immobilienverwertungs GmbH, ViennaGeneral design: ÖRAG (Österreichische Realitäten AG)Pit design: Keller Grundbau GmbH Consultant: 3P GeotechnikQuantities:

» 1,125m FoW piles ø 52 cm » 900m Soilcrete® jet grouting lamellae » 720m temporary strand anchors » 600m² shotcrete » 15,500m³ excavation » 5 months dewatering

Execution period: August 2016 – May 2017


PROJECTSPROJECTS

C ore drillings showed ine sandy silts starting from a depth of 13m. That’s why the loads of the building could only be transferred by a deep foundation. Using big equipment for the pit support and

the deep foundation was not possible due to the limited space available. Instead of securing the pit as originally designed by a Berlin sheeting, a pile wall with Soilcrete® jet grouting spacing was installed. For the foundation, MESI steel tube piles were installed from the bottom of the pit, instead of the designed partial displacement piles.

As a irst step, starting from an advance excavation, CFA piles with 55cm diameter were drilled with a specially adapted anchor rig. For sealing the spacings between the CFA piles, Soilcrete® lamellae were jet grouted. The pit support was necessary from three sides, on the fourth side the pit was already secured by an existing sheet pile which was needed for the construction of the underground garage and was left in the soil. The three sides of the bored pile wall were connected with head steel bars and the long side braced against the sheet pile.

Once the excavation was complete, a mobile crane lifted the 17-tonne rig into the pit to install the MESI piles with depths of 35m. Additionally, energy probes were put into the piles for the use of geothermal energy.

The limited space, the hustle and bustle of the neighbouring streets during the Christmas period, together with the bad soil conditions, made this small project a real challenge. Thanks to the high lexibility of our in-house equipment pool, rigs were provided which were specially adapted to the small size of the construction site and so the diferent products for pit support and foundation could be carried out.

PROJECT DATA

Customer: Haberl Baugesellschaft mbH, LustenauGeotechnical consulting and support: Geotechnik Dönz GmbH, SchrunsQuantities:

» 20 CFA piles, total 140m » 20 Soilcrete® jet grouting lamellae and connection columns » 29 MESI piles, total 939m

Execution period: December 2016 – January 2017 (11 days in total)

Gerhard Meyer Keller Grundbau

Dornbirn

AUSTRIABregenz

A SMALL PIT TAKES CENTRE

STAGEPit support in limited space conditions

O riginally a pile foundation was planned in the northern part of the construction area to transfer the loads of the 9- to 14-storey buildings safely into the ground and at the same time minimize

the occurring settlements.

The main contractor, Rudolf Gerstl KG, was awarded the contract for the foundations of the continuous basement and of one of the residential buildings. Due to the tight construction schedule and the small budget, we were asked to design an economical and fast alternative. So we came up with bottom-feed vibro concrete columnsOn the whole construction area, 2,130 columns were installed. The weak soils were displaced with the depth vibrator without generating spoil and all the columns were installed into a competent stratum.

By monitoring the display of the working parameter in the vibrocats, e.g. power consumption of the depth vibrator in the individual stages, we were able to install every column to the required depth, although the depth to

the competent soils varied across the site. The installation material, a con-crete compactible with the depth vibrator using an appropriately graded aggregate, was mixed on site.

Additionally, we installed a part of the designed pit support as a contiguous bored pile wall. In the course of the pit support, further piles were installed as support for the tower cranes.

We were able to inish the works with two rigs within two weeks to the full satisfaction of the customer.

PROJECT DATA

Investor: Wohnbau gemeinnützige Wohn- und Siedlungsgenossenschaft GmbHCustomer: Bauunternehmung Rudolf Gerstl KGDesign: Dorr, Schober und Partner ZT GmbHConsultant: Dr. WürgerQuantities:

» 2,130 vibro concrete columns » 46 FoW piles

Execution period: February – April 2017

Vincent Winter Keller Grundbau

Vienna

NEW HOUSING SPACE ON SOLID GROUND

On the former premises of the Hoerbiger valve plants in the Braunhuberviertel in Vienna’s 11th district, a new residential complex with seven buildings and 506 apartments is being constructed. Keller Grundbau designed and installed an alternative foundation solution by using bottom-feed vibro concrete columns.

AUSTRIAVienna

Next to Bregenz city centre, in the Altgasse, a ive-storey residential and oice building is being built between a house, an underground garage and a street leading to the pedestrian area. Lake Constance is only 215m away from the construction area and, as expected, the soil conditions were bad. The ill in the basement area (consisting of brick and wood residues), the sands and also the narrow spaces in the inner city meant a pit support was required.


PROJECTSPROJECTS

T he investor Gemeinschaftskraftwerk Inn GmbH (a JV consisting of TIWAG-Tiroler Wasserkraft AG, Engadinger Kraftwerke AG and Verbund AG) awarded the JV GKI WOB (consisting of Porr Bau

GmbH and Teerag Asdag AG) the contract for the construction of the weir Ovella. The JV itself assigned the construction of all ground engineering works to another JV - ST GKI Ovella (consisting of Keller Grundbau and Porr Bau – ground engineering department).

In addition to the works, the JV ST GKI Ovella was also employed to design the excavation pit for the weir. The design was developed in cooperation with ZSZ Ingenieure ZT from Innsbruck taking into account speciications and framework conditions stated by the investor and the consultants in-volved.

Several small works were executed in 2014 and 2015. In February 2016, the ground engineering works for the pit support of the Ovella weir started. Due to some delays resulting from the preparation works in the area, the works were carried out in day and night shifts as ordered by the investor.

The support for the 16m deep weir pit was designed as a spaced bored pile wall and the spacings were then sealed with jet grouting columns. To retain the wall and to minimise damage in case the neighbouring river Inn looded, it was anchored in several strata with up to 50m long strand anchors. The piles and the Soilcrete® jet grouting columns were both drilled to a depth of 45m to take advantage of the water-impermeable rock layer with regard to dewatering.

At the start of the piling works, the complexity of the pit support in the al-pine soil became clear. The underground consists of very hard rock, den-se layered sediment and gravel strata. In some parts, boulders of several meters diameter were found. Those led to a huge wear of drilling equip-ment and rigs. Not only the geological conditions, but also the execution of the deep piles and Soilcrete® columns held up the works, meaning the anchoring was carried out mainly in the winter months. The extreme wintry conditions in the Swiss border region complicated the works signiicantly. The 50m long 12-strand anchors were installed below the water table of the river Inn partly with high water encroachment from the drilling holes

and required immediate sealing measures between anchor and bored pile to keep the water inlow to the pit as low as possible.In January 2017, in the course of the anchoring works and the ongoing excavation, the dewatering started. Immediately the technical success of the pit support became clear, as the residual water stayed far below the li-mits which were set by the client and the consultants.

In spite of the geologic, climatic and topographic challenges, the pit was handed over to the client in April 2017. After the weir is completed and the river Inn rerouted by the client, the second phase of the ground engineering works in Ovella is scheduled to start in mid-2018. For the second phase, again bored pile walls with jet grouting spacing will be used. Also, diverse grout curtains using Soilcrete® jet grouting and foundation piles for dife-rent parts of the plant are planned.

AUSTRIA AND SWITZERLAND INVEST

IN CLEAN POWERGround engineering works for the GKI power plant

In 2014, the construction works for the joint venture power plant Inn started. The power plant is meant to provide 400GWh hydropower after a construction period of six years. The plant sprawls from the Martina reservoir in the Swiss municipality of Valsot via the Ovella weir on the border between Austria and Switzerland up to the powerhouse in Prutz.

PROJECT DATA

Investor: Gemeinschaftskraftwerk Inn GmbHCustomer: JV GKI WOBVeriication consultant: DI Dr. Jörg HenzingerDesign: ZSZ Ingenieure ZT GmbH Quantities:

» ca. 5,750m bored piles » ca. 5,900m Soilcrete® jet grouting » ca. 3,600m anchors » ca. 1,300m soil nails

Execution period: February 2016 – April 2017

Devid Wolfsgruber Keller Grundbau

Innsbruck

AUSTRIAOvella


PROJECTSPROJECTS

T he works had to be executed in relatively limited space next to and behind the existing building. The slope, with a depth of a maximum 17m, reached more than 3m into the upcoming ground

water, meaning the pit support had to be impermeable. With a very tight time schedule, the uphill and the lateral slope as well as the existing building itself were secured temporarily for the safe excavation of the pit by using anchored Soilcrete® jet grouting elements. To avoid any horizontal movement, 15m-long pre-stressed strand anchors were installed. Additionally, massive sheet pile constructions and existing reinforced concrete walls had to be restrained with grouted tension piles.

Besides simple convergence measurements, an inclinometer was installed as an additional monitoring tool on the uphill Soilcrete® wall, on which regular control measurements were taken. Until completion of the excavation pit and for some additional time afterwards, almost no horizontal movements were recorded and therefore the chosen ground engineering calculation model proved to be the right one.

A BROAD PRODUCT RANGE PAYS OFF

Keller Grundbau, as a universal provider of ground engineering services, was entrusted with the support measures for the excavation pit. Our wide experience, diverse techniques and quick execution were the key to success for this project. All boundary conditions given by the customer could be taken into account, starting from additional soil investigation, to supplementary shotcrete works on the slope, to foundation piles for a crane which had to be set up in exposed position. Permanent and close co-

operation with all involved parties and a high level of lexibility were crucial, to avoid any interference between the demolition works, earthworks and ground engineering.

SPOT-ON LANDING! After seven weeks of accident-free working during snowfall and sunshine, our job was handed over to the customer exactly on the day stated in the construction schedule and therefore the pit could be released for the inal excavation.

SPECTACULAR PIT SUPPORT IN SALZBURG’S

GROSSARL VALLEYExtension of the Waldhof children’s hotel

The 4* Waldhof children’s hotel, owned by the Prommegger family in Großarl, has a long tradition. In 2017, a big extension was built, which required comprehensive ground engineering works.

Marko Schmölzer Keller Grundbau

Salzburg

AUSTRIAGroßarl

PROJECT DATA

Investor: Family Prommegger, GroßarlProject management: Prommegger Baumanagement GmbH, GroßarlCustomer: RHZ Bau GmbH, SalzburgConsultant / Geotechnical design: geo² ZT-GmbH, HalleinStructural design: Hettegger ZT GmbH, GroßarlQuantities:

» 2,150m3 Soilcrete® jet grouting » 4,000m pre-stressed strand anchors

and grouted tension pilesExecution period: March – May 2017

Our oice in the city of Salzburg has been a consistent part of the Austrian Keller branches for more than 25 years. Through the decades, the local market has featured an increasing number of ground engineering projects in the southern parts of the Salzburg region, especially Pongau and Pinzgau. That is why we moved our oices from the city to a more central location - Eben im Pongau.

Next to the A10 highway, at the Eben exit, we found ideal oices including a small yard. So, from now on you will ind us at the following address:Keller Grundbau Ges.mbH

Gewerbegebiet Gasthof Süd 173

5531 Eben im Pongau

The team is looking forward to your visit!

From the city to the countryside –

new location for the Salzburg oiceBy the way,

our contact details stay the same. You can still reach us by phoning

+43 662 628 202 or by emailing Oice.Salzburg@

KellerGrundbau.at.

f.l.t.r: Dominik Struber, Marko Schmölzer, Kevin Fauland, Gudrun Fitzga


PROJECTSPROJECTS

T he renowned Austrian construction company Steiner Bau are the main contractor. In September 2016, they contracted Keller Grundbau to carry out all of the geotechnical works, which is split

into three blocks – retaining structure, the excavation pits for the main building and the tailwater.

RETAINING STRUCTURETo seal the retaining structure, we installed a cut-of wall on both sides of the river. The wall extends up to 20m into the subsoil.

EXCAVATION PITS FOR THE MAIN BUILDING The construction of the main building is split into two phases. In the irst,

the so-called right pit and its structure were built. After completion of that structure, the river Salzach was rerouted over that part and we started with the works for the “left pit”.

Keller Grundbau designed an alternative solution for the pit support. The solution involved the installation of a spaced bored pile wall and gap sealing with jet grouting. For retention, we installed ground anchors with lengths up to 33m in three strata. Additionally, a jet grouting slab braces the walls.

TAILWATERAt the tailwater, existing sheet piles needed to be supported. Therefore, we will use approximately 220 ground anchors. Also, we installed foundation blocks by jet grouting for the future bridge “Grieser Brücke”.

We started the piling works for the “right pit” in October 2016. Two rigs had to bore piles to a depth of 25m. Subsequently, we carried out the jet grou-ting and the anchoring.

The lowest level of the anchors is about 8m below ground water level, which led to signiicant encroachment during drilling. Together with extremely low temperatures in January and February this year, that presented a big chal-lenge to our people on site and the project team.

In spite of the challenging conditions, we were able to hand over the “right pit in March 2017 as scheduled. The works on the left pit started in Oc-tober (after rerouting the Salzach) and is planned to be handed over next January. The installation of the cut-of wall started in August and was inished in October.. Depending on the water condition of the Salzach, the permanent anchors will be drilled during the winter season 2017/2018.

MORE CLEAN HYDRO POWER

Construction of the power plant at Gries in Pinzgau area

In Bruck an der Großglocknerstraße, along the river Salzach, a new hydro power plant is being built. With a performance of 885 MW, the Gries plant will generate 42 million kWh of clean power per year and will supply electricity for more than 10,000 households. Two companies, Salzburg AG and Verbund, provided the investment of approximately 50 million Euros.

Johannes ZaunerKeller Grundbau

Linz

AUSTRIAGries

PROJECT INFORMATION

Investor: Salzburg AG und VerbundCustomer: Steiner Bau GmbHGeotechnical consultant: GDP ZT GmbHDesign: Kratzer ZT GmbHQuantities:

» 2,800m bored piles DN 880 mm » 5,100m strand anchors » 6,300m³ jet grouting » 27,000m² cut-of wall

Execution period: October 2016 - April 2018 (scheduled)


PROJECTSPROJECTS

K eller-MTS AG, the Swiss branch of the Keller Group, was awarded the Soilcrete® jet grouting works for the hotel in December 2016 by the main contractor Eberli Generalunternehmung AG.

The jet grouting works performed diferent functions. In the interior of the existing complex, foundations and walls were underpinned and the foundations reinforced. In several other places, dense excavation pits were constructed for the lifts. And to ensure a suicient level of earthquake resistance for the existing structure, some columns were reinforced with central steel bars.

Outside of the existing building, the underpinned columns for the historic entertainment hall performed a sealing function at the same time. Other sealing works were executed in the area of sheet pile junctions and the extensions of the sheet piles. Thanks to eicient time management, the contract was extended to include two other jobs. In one, the deepest bracing levels of the sheet pile walls were replaced by strutting Soilcrete® cross walls. And in the other, we were required to complete a further pit support with a sealing function.

The subsoil in the construction area consisted of clayey silt with difering proportions of sand and of silty gravel with sand. Locally, rocks and blocks were found. As a result of the heterogeneous soil conditions, the density of the respective layers varied signiicantly. Ground water was held on a level slightly below the working platform by dewatering - a big challenge. Keller-MTS installed approximately 480 Soilcrete® columns with diameters from 120 to 240cm and depths up to 18.5m. In total, 4,400m of drillings were bored and 3,000m of Soilcrete® jet grouted. Using the ACI® method enabled us to successfully realise diverse project outcomes. All Soilcrete® works were inished by the end of June 2017 within a construction time of approximately 20 weeks and to the satisfaction of all stakeholders.

A technically sophisticated and innovative in-house design and excellent organisation on site, together with fast interaction between client, designer and executing companies made this project a special one. Thanks to all parties involved.

A 5* METHOD FOR A LUXURY HOTEL IN SWITZERLANDHotel Titlis Palace, Engelberg

The hotel, Europäischer Hof, built in 1904, is currently undergoing renovation. Investor Yunfeng Gao is planning a new luxury establishment which will be unique in the Swiss town of Engelberg. Breaking ground on 4 April 2016 also heralded a new era for tourism in the region. The renovation of the existing building is one part of the project. Additionally, a completely new annex will be built and the historic entertainment hall will be integrated into the complex. By the time it opens at the end of 2019, around 100 billion Swiss Francs will have been invested in the 5* hotel.

PROJECT INFORMATION

Investor: Han‘s Europe AG, Engelberg, chairman: Yunfeng GaoClient: Eberli Generalunternehmung AG, SarnenDesign: CES Bauingenieur AG, SarnenPit design: Keller-MTS AG / Keller Grundbau Ges.mbH / CES Bauingenieur AGConsultant: Keller+Lorenz AG, LuzernQuantities:

» 3,000 m Soilcrete® columns Execution period: January – June 2017

Markus Rupnig alle Keller-MTS AG

Ennetbaden

SWITZERLANDEngelberg

KB 1-2 working in the interior of the existing hotel

Execution of the strutting Soilcrete® cross walls for the bracing outside of the building

Thomas KimpritisTimo Ackermann

Underpinning of the historic entertainment hall, exposed Soilcrete® elements


PROJECTSPROJECTS

T o meet the requirements for the designed cut-of wall with a thickness of 35cm, Keller-MTS proposed the DSM method. With the triple paddles, the execution of 50cm thick cut-of walls is

easily possible. Based on the experience of the Keller group and on various tests, we were able to develop an extraordinarily strong mixing tool, which worked well on this job, where blocks of 35cm in diameter had to be pierced in partly very compact and abrasive soils, and partly in loosely bedded sandy gravels.

Given the fact, that the road along the shore was regularly used by lorries, it was necessary to implement a ield trial in advance. The trial proved the stability of the cut-of wall, its thickness and its consistency, so that we could start with the installation.

The project was split into three parts, to minimize the impacts on the local residents and the companies in the area, as for approximately 75% of our works one lane of the road had to be closed and the traic had to be restricted accordingly. Before starting work, the road surface had to be cut by a width of approximately one meter to enable the soil penetration with the mixing tool. Then, a trench for canalisation of the backlow was cut. The backlow was brought to the disposal site once it was slightly hardened.The execution of the DSM columns was monitored precisely and the execution parameter were recorded. In addition to that, quality tests were done to check the permeability and stifness of the cut-of wall.Special attention had to be paid to environmental protection, as existing trees along the dam and rare plants next to the river had to be preserved.

Discharge of waste water was also subject to strict controls. Also in some parts, the cement suspension pumps could be installed only at a distance of a kilometre from the rig.

We completed the job to the full satisfaction of the customer within only four months.

FLOOD PROTECTION ALONG THE RIVER RHÔNE

DSM cut-of wall in the French part of Switzerland

In the third phase of the Rhône correction, Keller-MTS was awarded with the works for a cut-of wall between the towns of Riddes and Aproz. This aimed to improve the existing dam in Aproz to a length of more than 1,600 m and to protect the town from looding.

PROJECT INFORMATION

Investor: Canton of Valais – Department for mobility, regional development and environment Customer: JV Rhône 3 – Aproz (Dénériaz, Evéquoz, JPF)Consultant: Géoval SADesign: SD Ingénierie SAQuantities:

» 16.000m² DSM cut-of wallExecution period: March – June 2017

Thierry Oechsel Keller-MTS SA

Vétroz

SWITZERLANDAproz

You can reach the team in Vétroz via the following contact details:

Keller-MTS SA

Route du Rhône 6

Case postale 50

1963 Vétrozphone: +41 27 722 65 85

fax: +41 27 722 37 90

[email protected]

Vétroz – our new location in the

canton of Valais

Since the spring, our oice in the French part of Switzerland is no longer in Martigny. To meet the increased requirements caused by a higher number of sites, we found a new location in Vétroz, where the oice is located next to a modern yard and a small workshop.

f.l.t.r.: Thierry Oechsel, Balbine Miserez, Mathieu Burgun, José Lopes, Alessandre Dussourd, Milica Aleksic


PROJECTSPROJECTS

V isionary is a very modern oice project, which is located close to the metro station Nádraží Holešovice and therefore it provides access to four public means of transport - train, metro, tramway

and bus.

The building will provide a good number of services, not only for the tenants, but also for the surrounding residents. In the publicly available yard behind the building, a multifunctional playground and an open-air cinema will be installed and a restaurant and a café will open.The tenants will enjoy a great view of the botanical garden and a sunroof will include a jogging track. After completion, the project will be certiied according to the LEED Platinum requirements. The oice building will include three loors below ground - with 214 parking spaces - and seven loors above ground. It will be equipped with six high-speed elevators.The subsoil consists of a manmade ill in the upper part, characterised by ash and unburned carbon from steam locomotives. Up from 5.5m depth, there is silty sand gravel and gravel with stones of up to 25cm in diameter. This is underlaid by weathered and partly weathered shale up from 8.5m. Ground water is found at the upper edge of the shale layer, so the deepest excavation level of the pit is approximately at 3.5m below ground water level.

Taking into account the geological conditions, it was necessary to design and execute the pit support as a technically waterproof sheeting construction. Therefore, we developed and analysed diferent technical and economical alternatives during the tendering phase. Based on that

data, the client chose the pit support by the means of a temporary overlapped bored pile wall.

The pile wall was executed with piles of 90cm in diameter, which were bored in a centre distance of 70cm between the primary (unreinforced) and the secondary (reinforced in the full length) piles. The wall embeds into the waterproof rock at least 2.5 m below the deepest excavation level. The surface of the pile wall was meant to serve as a so-called lost formwork for the reinforced concrete walls of the ground loors, which were executed as white tank. In order to guarantee the impermeability of the pit, the piles had to be bored with a casing to a depth of at least 1.5m below the deepest excavation. To stabilize the sheeting construction, temporary anchors with four to six strands were drilled in one stratum. In some areas, the primary piles were anchored directly on steel plates, in others steel walings were installed on the pile wall before anchoring. Removing the anchors after their use was not necessary.

The piles were executed on a level of 1.5 to 3.6m below the ground surface into concreted guidance walls. The advance excavation to the working platform was sloped and partly had to be secured by a Berlin sheeting.

To meet the very tight time schedule set by the customer, four drilling rigs were active on site. A Soilmec SR45 did the shorter drillings for the Berlin sheeting, for the drilling of the bored piles a BG20, an SR60 and an SR75 were used.

The surface of the pile wall was levelled with a timber construction during excavation. The timber construction consisted of 10x10cm proiles, which

were ixed to the pile wall in distances of 50cm and two layers of 15mm OSB boards which were put in between. The proiles were ixed on the pile wall top-down during excavation and the OSB boards were then installed after excavation from the deepest level. Before installing the OSB boards, the distance of the outer edge of the reinforced concrete wall to the pile wall was measured geodetically and so it was possible to compensate diferences. As the pit support was built as a technically waterproof construction, water could intrude only through cracks in the bedrock or through eventual discontinuities in the pile wall. During excavation, the static ground water proportion and rainwater had to be pumped. In case that small water intrusion was detected in the pile wall, the respective areas were sealed immediately by the means of low pressure grouting. The emerging water was pumped only from local cavities and a dewatering system was not necessary. Beforehand, two iniltration wells were drilled outside of the pit. At the end, the residual water in the pit was that little, that those wells

were not used at all. That fact illustrated, that the technical solution for pit support chosen during the tender phase, was the ideal one for the project.

The qualitative high-class execution of all involved companies enabled the construction of a deep excavation pit with a cubage of 48,000m³ in a very short time. An important factor to reach that performance was the ability to transport the excavation material directly by train from the nearby station to the disposal site.

The completion of the works in time and to the required quality was a ine achievement for all involved. Also, our international company beneitted the project by enabling us to use the know-how of worldwide working specialists. Work safety and environmental protection were given the highest priority during the whole execution to meet the strict guidelines of the international companies Skanska and Keller. That was visible on site and provided our employees with the framework to inish this demanding project without any accidents.

A VISIONARY PROJECT IS BEING BUILT IN PRAGUE

Deep excavation pit next to the Vltava River

Visionary is an oice building currently being built in Prague’s Holešovice quarter next to the Vltava River. To build it on a plot surrounded by three streets, a 4,200m² excavation pit had to be installed to a depth of 11m.

PROJECT DATA

Investor: Skanska Property, a.s.Customer: Skanska, a.s.Consultant: Mgr. Martina BaborováGeotechnical Designer: Dipl.-Ing. Jaroslav PlívaQuantities:

» 418 bored piles ø 90cm, 4,071m » 128 temporary strand anchors, 1,730m » 125m² temporary Berlin sheeting » 2,133m² pile wall surface » 293m pit perimeter » 48,000m³ excavation

Execution period: July – October 2016

Jan KubešKELLER - speciální zakládání, Prague

CZECH REPUBLICPrague


PROJECTSPROJECTS

Peter Jurik Keller špeciálne

zakladanie, Bratislava

SLOVAKIABratislava

T he development area is split into two zones – “Viladomy” which consists mainly of low-rise residential buildings, urban villas and family houses, and Mesto which is adapted for people who

want urban housing in combination with being close to nature. Started in 2010, the completion of the project is planned for 2030, whereas the irst residents moved in already in 2013.

The subsoil in the respective area is composed of quaternary soils; mainly loose till, middle dense gravel with a top layer of clay and sandy silt.

Depending on the respective subsoil, an adequate foundation is necessary. Partly, the soil was improved using the vibro compaction method up to a depth of 5m. In other parts, 5m deep vibro mortar columns were installed.

As reliable partner, Keller has worked on ten phases of the project so far and we are looking forward to a great collaboration on future parts of the project.

SUNFLOWERS GROW IN THE SOUTH OF

BRATISLAVAUrban development project “Slnečnice“ in Petržalka

The urban development project “Slnečnice” (Slovak for sunlowers) comprises the construction of several residential buildings in an area of 50 hectares. The investor, Cresco Group, has developed a new quarter which combines proximity to the city centre with living in a peaceful environment.

PROJECT INFORMATION

Investor and customer: Maschinenbau Volgger GmbHConsultant: Geo3 - Bürogemeinschaft für angewandte GeologieDesign: Dr. Ing. Piero BernabèQuantities:

» 7,200m ductile piles 118/7,5, grouting diameter 270 mm

Execution period: September – October 2017

Devid Wolfsgruber Keller Fondazioni

Brixen

PROJECT INFORMATION

Investor: Cresco Group, a.s.Customer: diverse Consultant: RNDr. LesickyQuantities:

» ca. 19,000 m vibro compaction » ca. 15,000 m vibro mortar columns

Execution period: July 2011 - ongoing

MORE SPACE FOR MACHINE

CONSTRUCTION… but on solid ground

The machine construction company Volgger in Freienfeld / Sterzing (South Tyrol, Italy) is expanding its facilities. In September 2017, we started the deep foundation works for the new production hall, using ductile driven piles.

T he existing, adjacent building, constructed in 2008, is founded on driven piles. Therefore, the geological conditions in the area were already well known. The upper layer of 3 to 4m, consisting of

extremely dense bedded ill, is followed by silty and partly also peaty soils to depths of 18m, which would mean considerable settlements for the 2,300 m² hall and the high-bay racking inside. This is why a deep foundation by means of piling was necessary to transfer the loads into the sand-gravel layer at 18m depth.

The skin friction values obtained during driving conirmed the designed pile length of 25m. As the new building is located next to the old one already founded on driven piles, the ductile piles had to be driven 50cm in front of the existing neighbouring wall in some areas.

In the area of the high-bay racking, the piles were driven in a smaller grid due to the higher loads and requirements for settlement limitation. During execution, static load tests were done to prove the bearing capacity and the settlement behaviour of the piles.

The pile driving was completed after only four weeks according to the schedule, so that the construction of the building could start as planned.

ITALYSterzing


PROJECTSPROJECTS

T he existing railway is currently operating as a single track, as will the 1,650m extension. It includes three new stations: Porto (which is in the harbour area), Politeama (next to the same named theatre) and

Malaspina (underneath the street of the same name).

Tecnis SpA was awarded the tunneling works for the underground tubes. They contracted two companies for the ground engineering works – Mar-chese Group is executing the retaining walls by means of double rowed CSP and CAP piles and Keller Fondazioni is sealing the slab by the means of So-ilcrete® jet grouting.

The average width of the excavation area is about 7.0m, whereas the maxi-mum height of the excavation from ground level is around 12.0m (thus the maximum empty drill). The maximum thickness of the sealing slab is 8.5m (average 6.0m). Thus, the maximum drilling depth is about 20.5m, which can be done with the KB 7 rig which is being used for the works.Most of the contract is located within Palermo harbour, but the works for the last section need to be carried out in one of the most important and populated streets of the city centre. The working area features diferent types of soil, ranging from sand or silty sand, especially in the harbour area, to layers of cemented sand and weathered sandstone when moving away from the harbour and going towards the city centre. The water level is loca-ted at about 1.5 m below the working platform.

Before starting the works, a trial test was arranged to check whether the designed diameter of 150 cm could be improved and, consequently, the grid too. Some tests were carried out using the ACI® method, as well as some core drilling to check the permeability, and the chance to increase the diameter was veriied and conirmed.Due to the diferent types of soil to be tackled in the various sections, it was decided that the ACI® tests should be repeated every time that some signiicant diferences arose in the soil conditions.

The works started in November 2016. A one-shift work schedule has been applied and, so far, about 45% of the sealing slab has been completed, due to the many delays caused by preparation works not inishing on schedule. It seems quite likely that the contractual deadline (originally set for Decem-ber 2017) will therefore have to be postponed.

SOILCRETE® SEALS THE SLAB IN PALERMO

Metro network’s extension in Sicily‘s famous city

The metro in Palermo was built in 1990 and is used daily by thousands of people. To close the ring around the city, it is undergoing an extension connecting the underground track on the section between Notarbartolo and Giachery stations and adding a new station at Politeama. The total investment is 104 m€ and completion is planned for July 2018.

PROJECT INFORMATION

Investor: RFI – Rete Ferroviaria Italiana S.p.A.Customer: Tecnis S.p.AQuantities:

» 68,000m³ Soilcrete® for sealing » 108,700m empty drill

Execution period: November 2016 – April 2018 (scheduled)

Emanuele Nanni Keller Fondazioni

Verona

ITALYPalermo

Partly existing track, partly in planning stage

Scope of works - Keller Fondazioni


PROJECTSPROJECTS

O slo is the fastest growing city in Scandinavia and this project will provide additional space for growth in the coming decades. It will also reduce the travelling time between Oslo Central Station

and the transport hub in Ski by 50%. A twin tube tunnel, mostly embedded in solid granite, will allow trains to run at 250 km/h. The budget of Euro 1.53 billion combined with ive EPC contracts (including 4 TBMs) will mean that the irst trains will run by December 2021 – 6.5 years after the start of the project.

The main construction works started in 2015 and will be completed by 2020, so that the railway and signaling works can start ahead of passenger services beginning. Mainly, the trains will run in a twin tube tunnel, before entering Oslo in a section which will be created by Cut and Cover and Top Down methods. In Ski, there will be an open section, protected by retaining walls on both sides, before entering a new station.

The sections of the project where the tunnel is entering from clay and quick clay into solid granite are the geotechnical challenges, due to the sensitivity of handling such soil during construction. Keller is carrying out the main foundation and retaining works in Oslo and Ski using various geotechnical methods to ind the best solution for the heterogeneous soil conditions. Keller, as a worldwide geotechnical contractor, started the project in May 2016, supported by three business units to carry out the diferent techniques. An international team, representing nine nationalities from all over Europe from Greece to Finland, are working together on the project.After a period of 17 months, carrying out various techniques, the team has completed around 90% of the main works of the original contract. As Keller was able to ofer diferent geotechnical techniques for a safe excavation of the tunnel close to Oslo Central station, the team was able to increase the contract value to more than Euro 20M. As the project is located in the former harbour of Oslo, all works need to be planned in close co-operation with archeologists, as parts of a Viking ship were found at site, as well as a graveyard. Due to the present soil conditions

and the ongoing design, many last minute changes were necessary which required enormous lexibility from the team at site but also from the equipment department to complete the works in time. The contribution of all Keller workers from the diferent business units and Keller’s large equipment pool are the reasons that the works were handed over in time, even with the short notice for changes in the design.

The teams from the South East Europe business unit are travelling more than 1000km to Norway each week, leaving their homes and families to support the project with their knowledge and expertise. These people are the key to success for Keller.

Therefore, the team spirit at site is very important and needs to be looked after carefully. We were lucky when we got the chance to rent a whole house directly beside one of the main working areas, where one of the Austrian workers is usually cooking lunch and dinner for the whole team. Everybody working far away from home appreciates traditional food from home like “Goulash” as well as “Cordon Bleu”, and steaks and sausages from the barbeque. For the daily accommodation, apartments in the famous Bar Code complex in the centre of Oslo have been provided.

Being far away from home, travelling week by week for more than 17 months, the simple things, like food and housing make life a bit easier for everybody, even when the weather conditions and the project are diicult. A good atmosphere at site is essential for the success of the project and necessary for our Keller slogan: Think Safe, Work Safe, Go Home Safe.

The project in Oslo will run until June 2018 with all kind of geotechnical works carried out by specialists from South East Europe. This major project is the perfect opportunity to present Keller and our various geotechnical techniques to the Norwegian construction market.

The Project Management team would like to say THANKS to the whole team working on all diferent contracts of the Follo Line Project for their daily commitment to make this project a success for Keller.

THE FOLLO LINE PROJECT IN OSLO

IS ON TRACK……and Keller joins the ride

The Follo Line Project is the largest infrastructure project in Norway. It will include the country´s longest railway tunnel, which will be more than 20 km long. Named after the Follo Mountain, which the twin tube tunnel is passing through, this is the most important infrastructure project for the future of Oslo and its suburb of Ski.

PROJECT INFORMATION

Investor: Bane Nor – Norwegian railwaysMain Contractor: Condotte d´aqua S.p.A in Oslo / Obrascón Harte Lain S.A. in SkiIndependent Veriicator for geotechnical worksNGI- Norwegian Geotechnical Institute for Oslo / Multiconsult for SkiQuantities:

» 500,000m Deep Soil Mixing (i.e. 37,000 columns with 80 cm diameter with up to 3 rigs)

» 30,000m Soilcrete® jet grouting, diameter of 80cm and 120cm (with up to 2 rigs)

» 47,000m micropiles (i.e. 1,500 steel core piles 273mm casing /150mm steel core with up to 5 rigs)

» 20,000m permanent and temporary anchors with 6-14 strands (up to 3 rigs)

» 3,000m rock grouting prior to tunnel excavation (1 grouting unit)

» 500m core drilling (100mm cores for soil and rock investigation – 1 rig)

» Monitoring: inclinometer, piezometer, load cells, extensometer

Execution period: May 2016 – June 2018

Dominik Gächter Keller Grundbau

NORWAYOslo / Ski

Fig. 1. Folloline Project Map – Oslo S to Ski (BaneNor 2015)

Oslo S

As

SkiKolbotn

Langhus


PROJECTSPROJECTS

I NNNES is a leading importer and wholesaler in Iceland, focusing on high quality food products, including market-leading brands from across the world. Due to expansion it needs a new distribution and logistics centre.

The new warehouse is located directly in the harbour area, very close to the shore of Reykjavik with direct connection to the harbour and the docks. The building is divided in sub areas such as frozen high bay racking, dry high bay racking, distribution and oice area. Due to the location and the climate in Iceland, compression and tension piles (due to the strong breeze) have to be installed to ensure the stability of the building. In addition, the settlements are an important factor, as the automatic warehouse system is very sensitive to diferential settlements. The client asked for a pile foundation and therefore got in contact with Keller, as no Icelandic contractor is able to execute these works. The geo-

technical investigation indicated that the bedrock is at a depth of 10 to 35m, which is an additional challenge for the designers due to the strict re-quirements for diferential settlements of the automatic warehouse. Our solution consists of a combination of ductile piles, which are installed as compression piles, and double corrosion protected bar anchors, which will serve as tension piles. The KDP – Keller Ductile Pile was chosen for the execution of the compression piles because of the high production rate compared to other piling products.

The execution time was a key factor for the owner and one of the reasons why Keller was contracted. For the foundation of the whole building in total approximately 32,000m ductile piles and 3,300m bar anchors will be installed.

As there is very limited information on ground conditions available, Keller carried out a ield trial to improve their knowledge of the soil. With the exe-

cution of the trial, the bearing capacity as well as the load-settlement be-haviour was checked before starting the inal design of the pile foundation. Paul Pandrea and Cecilia Bohn, both part of the Corporate Service Depart-ment in Ofenbach, Germany, were involved from the beginning to advise the external designers using Keller´s experience from piling and design works.

The piles and anchors for the trial were installed in the middle of August and successfully tested during September to prove their performance. After the inal test evaluation the contract was signed at the beginning of Oc-tober. The execution of the main works started in the middle of November and will take about four to ive months.This project is very challenging as there is no great experience of piling in Iceland. In general the bedrock, in form of volcanic material, is close to the surface so no piles are required for the buildings.

Given the fact, that the transport of the prefabricated ductile piles as well as all drilling equipment from Austria by ship takes time, highly diligent pro-ject management is necessary to avoid any interruptions and deliver the requested performance.

We are keeping our ingers crossed that the team on site will handle the rough Icelandic climate during the winter well, especially the wind and rain in combination with the decreased daylight. Main foundation works will be commissioned in March 2018 so that the concrete and steel structure works can start in spring 2018.

Keller was able to win this project because of intensive cooperation with the owner, the designers and the great teamwork of Klaus Breit, Manager Special Projects, Dominik Gächter, Project Manager, the Corporate Service Department and Muhamed Mešić, our legal counsel.We would like to say THANKS to the owner and all partners in Iceland for the excellent cooperation and look forward to a successful execution of the project.

INNNES IS BUILDING THEIR FUTURE

on piles from Keller Grundbau

In Reykjavik, Iceland, INNNES is building a new 16,700m² distribution and logistics centre. Due to the geological situation of the site, a pile foundation is necessary to transfer the loads into the bedrock and avoid a large amount of settlement which can cause problems with the automatic warehouse system.

PROJECT INFORMATION

Investor: Dalsnes, Island & INNNES, IslandProject Management: Ferill, IslandGeotechnical Investigation: Verkis, IslandSlab Designer: Twintec, DeutschlandThird Party: 3P Geotechnik, AUSTRIAQuantities:

» 32,000m ductile piles 170/9,0mm » 3,300m bar anchors 63,5mm DCP » 8,750m geotechnical drillings 250mm » 35,300m grouting and compaction grouting

Execution period: » August – September 2017 (trial)) » November 2017 – March 2018 (main works)

Dominik Gächter Keller Grundbau

ICELANDReykjavik


COMPANY NEWSCOMPANY NEWS

IT ALL STARTED IN 1997…

Keller has been in the Italian market since 1997 and on June 25 the event was celebrated at the Hotel Pacher, at Varna, in the Trentino Alto Adige region. Apart from hosting our regional oices, Varna is also the place where our latest worksite is located, i.e. the “Isarco underpass” for the Brenner Base Tunnel.

OUR ENDURING GOAL: TEAMWORK

The event also provided the opportunity to enhance the team spirit among Keller employees. Family members were also involved and we all had a chance to strengthen and consolidate existing relationships. Team spirit has been the secret of our success, besides being the driving force that has allowed us to achieve such an important milestone, especially within a market that has become increasingly diicult, particularly over the last few years.

The invitation to celebrate was extended to all the Regional Managers of SEE, to the Division Managers, and to our Vienna-based colleagues headed by our BU Manager Andreas Körbler.We were delighted to see that also some of our customers’, suppliers’ and consultants’ representatives accepted our dinner invitation and took the time to celebrate with us.

THE IMPORTANCE OF LEADERSHIP

Emanuele Nanni, who’s been leading Keller Fondazioni since 2006, reviewed the 20 years of our corporate history by recalling our most successful sites, both in terms of technical performance and inal results. His very personal speech was enriched by some humorous and pleasant remarks, about challenging tasks and their solutions, about former colleagues and also about the daily business in the oice.It wasn’t easy to go through 20 years of history, since each site is part of us and of our corporate heritage. We recalled the most signiicant ones and the projects that have been most technologically innovative for the whole group, starting from the “Scianina Tunnel”, continuing with “Rome Metro B1 , the Oglio and Serio Viaducts , up to the last one, the Isarco Underpass”. Many other projects were also mentioned, as they’ve all been very important challenges in our history.

STARTING AGAIN, STRONGER THAN BEFORE

After a lovely dinner, the party went on and at the end of the evening we all felt ready for another amazing journey. We all wish to be together again to celebrate Keller Fondazioni’s many more anniversaries in future.

KELLER FONDAZIONI:

20 YEARS OF PASSION

AND INNOVATION

Keller Fondazioni is 20 years old - and such an important milestone needs to be celebrated. So we did by treating our employees to a weekend in Trentino Alto Adige.

Keller Fondazioni‘s irst site in 1997 - Campione d‘Italia



T he action plan is to increase our local strengths, which means on the one hand, developing our existing design and acquisitions team as 90% of our contracts are based on Keller solutions, and

on the other, building up a competitive site team and reducing costs, for example, equipment transport.

Consequently, new colleagues have joined the Keller oice, the number of the operators doubled from two to four in recent years, and a small work-shop has been set up near Bucharest.

Keller Romania has only one oice in Bucharest and considering the latest development in the market, especially in the residential building sector, our plan is to increase in other regions like Cluj-Napoca and Iasi, which are quickly developing as regional inancial centres.

Currently, the Bucharest oice is structured in three main parts:DESIGN AND ACQUISITION

» Laurentiu Floroiu – Team Lead » Bogdan Tanasoiu – Design Engineer » Bianca Cinzaca – Design Engineer

SITE MANAGEMENT » George Gomoescu – Site Manager » Vlad Petrila – Site Manager

ADMINISTRATIVE » Radu Dumitriu - Regional Manager & Acquisition » Diana Manu – Assistant

STAR RESIDENCE, CLUJ-NAPOCAAdapting a pile foundation solution to extremely variable soil conditions

This residential project on the outskirts of Cluj-Napoca includes two buildings with 10 storeys above ground, a total surface area of 1,500m2 at foundation level. The geotechnical study showed poor foundation ground down to depths of 27m from foundation level, followed by a granular layer. The top level of the latter was expected to have an 8% slope from one end of the site to the other. The design consisted of a raft foundation and 86 piles, drilled with temporary 900mm casing, and embedded 10m in the non-cohesive layer. The expected maximum design compression load at the top of one pile was computed to be 4,800kN. All piles were reinforced on the top 10.5m only, to account for the earthquake-generated horizontal loads (peak ground acceleration of 0.1g).

Local variations of soil layering led to an increase of total quantities to 100 piles and a maximum pile length of 43m. These variations peaked when the top level of the granular layer, recorded during drilling of two adjacent piles, dropped 8m over a horizontal distance of 4m. One explanation for such a variation is the presence, and later on dissolving, of deep salt deposits. This would also explain the high concentration of salt (NaCl) found in the ground water. In addition to that, inding the right concrete mixture formula was complicated by the consistent sulphate concentration that originated in the organic soil resting on the granular layer.

Drilling, concreting and partially reinforcing piles of 43m length posed a series of challenges, from technological to logistical ones, which further increased the complexity of the project.

Also, the contract included the design and execution of temporary retaining structures made of contiguous piles (620mm nominal diameter) and a granular distribution layer for lightweight adjacent structures. All necessary earthworks were also included in the scope of the contract.

PARK LAKE 2, CLUJ-NAPOCAFull displacement piles as settlement reducers

The Eastern part of Cluj-Napoca is perhaps the busiest this year in terms of residential projects. One of them, Park Lake 2, consists of two buildings with 10 storeys above ground and a third for parking purposes. The site is located right next to Lake Gheorghieni and represents the second phase of a larger residential complex.

The foundation soil consists of a top cohesive layer (stif) followed by a coarse granular layer that rests on cemented clay (very stif to hard). The raft foundations of the two tall buildings, having average widths of 15m, are able to safely transfer all loads to the unimproved soil. While the bearing capacity was not an issue, the computed settlements were exceeding the recommended limits.

Hence, within the framework of ASIRI’s Domain 2, the foundation soil was improved with the sole purpose of limiting the settlements. Full displacement piles (410mm nominal diameter) were placed right below the raft foundation, at a spacing that varied between 1.3 and 3.5m, and were embedded in the granular layer. The length of the piles varied as well, between 6.3 and 7.8m, a result of the soil proile variation. All piles were reinforced on the top 4m only, to account for the earthquake-generated horizontal loads (peak ground acceleration of 0.1g).

The foundation soil for the adjacent parking building was improved with a 50cm granular transfer layer, aimed at ofering a homogeneous support for the two underground loors structure. The contract included the design and execution of this layer as well, together with all other necessary earthworks.

KELLER GEOTEHNICAStaying strong in a challenging market

The current construction market in Romania is showing a dramatic decrease in volume, especially in public investments. Private investments, like wind parks, which were booming a few years ago have now stopped. Apart from this, the residential building and retail sectors have seen a constant and consistent increase during recent years. Subsequently, Keller Romania has adapted its strategy to these conditions.

PROJECT INFORMATION

Customer: Amistar Euroconsult S.R.L.Structural designer: GP Proiect S.R.L.Design of geotechnical works: Keller Geotehnica S.R.LConsultant: Prof. Augustin PopaQuantities:

» 1,900m FDP (410 mm) » 3,000m3 compacted granular ill

Execution period: June 2017PROJECT INFORMATION

Investor: CS Invest Consulting S.R.L.Customer: BT Development Soporului S.R.L.Geotechnical study: Geodesign S.R.L.Consultant: Prof. Augustin PopaQuantities:

» 3,662m piles (900mm only)Execution period: April to September 2017v.l.n.r.: Vlad Petrila, Bianca Cinzacă, Diana Manu, Laurentiu Floroiu, George Gomoescu, Bogdan Tanasoiu, Radu Dumitriu



Vincent Winter Keller Grundbau

Vienna

T herefore, the municipality of Vienna provided a property in the 22 district in the so-called Unteres Hausfeld . The geological conditions in the biggest urban expansion area (21 and 22 district)

are very homogenous, so the research indings can be used for many construction projects in the future.

In the course of the project, diferent ground engineering elements were carried out and tested, such as piles (cased bored piles and CFA piles), jet grouting columns, micropiles and anchors. The testing results of the efec-tive ground resistance in correlation to the respective ground engineering product will be then compared with the design values used so far, which ori-ginate from experiences or from literature.

The JV FPUH, a partnership formed by Porr and Keller Grundbau, were awarded the contract to carry out the testing and started the works in Ja-nuary 2017. Piling and anchoring works as well as the large-scale load tests and ancillary works were executed by Porr. Keller Grundbau was responsible for the jet grouting and micropiling.

This research project, with all the diferent products, is very special com-pared to the works carried out on a usual site. For example, every pile is in-stalled as a prototype with special constructions to eliminate the surface friction, in particular soil layers. Furthermore, they are equipped with diverse

sensors which measure strains and forces within the piles during the load tests. These special constructions guarantee that the surface friction and peak pressure of each pile are transferred and recorded only in the respec-tive soil layers which have to be investigated.

Currently, all testing piles and columns have been installed and the load tests are ongoing.

All involved parties have a common goal and are executing the research project fairly to receive valid scientiic results. In the course of the work some unexpected problems occurred. Those problems provide high en-gineering development opportunities like no other current ground en-gineering project in the Austrian market. It’s this fact which makes the par-ticipation in this project such a fascinating challenge for the engineers of Porr and Keller Grundbau.

GROUND ENGINEERING ON THE TEST BENCH

The municipality of Vienna carries out large-scale tests

Due to changing standards, the municipality of Vienna has had to carry out a ground engineering research project, especially in the most common types of soil in Vienna, the Danube gravel and the Miocene. The aim is to determine the limit load capacities of diferent ground engineering products in typical Viennese soils.

PROJECT INFORMATION

Investor / Customer: MA29 – Brücken- und Grundbau (magistrale departement for bridge construction and ground engineering)Design: Mayer ZT GmbHLoad test design and monitoring: TU ViennaSoil report: MA29 – Fachbereich GrundbauExecution period: January 2017 to spring 2018

Pre-fabrication of micropiles

Execution of large-scale load tests and jet grouting

AUSTRIAVienna



A nd now, after almost two years of planning and construction, the time has come – the new yard shines bright and is perfectly prepared to service our many sites. “Everything started with

requirement planning which involved a logistics expert and was dealt with together with our TPM (Total Productive Maintenance) project. The worklows and routes were analysed and the best possible structure was designed, said Equipment Manager Paul Rott. A gantry crane has been installed, which is crucial to manoeuvring the containers and rigs. “Now we can avoid the regular use of mobile cranes, which were rented when necessary. That constantly led to a lack of space, as the mobile cranes didn’t have any ixed loading area, Paul added. In addition to the gantry crane, the whole area was asphalted and the yard was cleaned out. At the same time, the yard and workshop were rearranged according to the 5S principle. The target of 5S is to organise the workplaces in a manner that the work can be done without disturbances. “Searching

for tools and long transportation and waiting times have been minimized. And the workshop looks much cleaner now,” said Workshop Foreman Ewald Ruprechter.

In Söding, around forty employees service a smooth operation that ensures our sites are equipped with the right items at the right time. “We carry out repairs and maintenance works for more than 70 large rigs and several pieces of smaller equipment. If necessary, our mechanics and electricians are also mobile and go directly to site if there is something urgent to be done. Additionally, all tool boxes are checked and maintained on a regular basis,” said Paul proudly. “We are happy to support our people on site and sometimes we also do the impossible.”

With the refurbishment, the foundation for further successful work has been laid.

REFURBISHMENT FOR OUR LOGISTICS HUB IN

SÖDING Our company is growing steadily and year by year we have more sites. This development also afects our team in the workshop and at the yard in Söding. Also, as the logistics hub for Southeast Europe, it dispatches several trailers daily and sites have to be prepared and provided with equipment in time. To meet the increased requirements, a modernisation of the yard was crucial.

DADDY, WHAT DO YOU DO AT WORK EVERY

DAY?

W hich father (and, of course, mother) doesn’t know this question. It’s the same with our Equipment Manager Paul Rott. He regularly got to hear it from his daughter Anna and after she

said at kindergarten that her daddy worked at Keller with construction rigs an idea was born – why not show the children what we do?

So, in June, we got a visit from 46 children from the kindergarten Hausmannstätten together with care people and some parents to see our workshop and the yard. After a short and child-oriented presentation of our company and products, all the kids were equipped with safety vests and helmets labelled with their names. They loved that they could take them home with them.

Two abreast, we visited the workshop and the yard, where our employees explained the equipment and tools. After a break where the children were served frankfurter with buns and drinks, we went over to the practical part, where the children were allowed to try some equipment on their own. So,

there was a station where the kids intensively tested the loading crane and the drill drive of our new Sonic rig. On the second station, the kids got a lift on a wheel loader. For this, the renovation of the yard was the ideal playground, where we removed earth from one position and brought it to another. Our new forklift was used for the transport of the kids from station to station. In the cabin, of course.

Paul was delighted that many colleagues came to work to take care of the children and their safety although they were due to be of that day. The works in the workshop had to be stopped as everyone wanted to take part in the practical exercises.

The children thanked us for the visit with a great song Danke, merci Firma Keller”. We also want to say ‘Thank you for the visit’ and we look forward to eventually meeting one or other of them in the future, maybe as part of the Keller family.


and a happy and prosperous New Year 2018. We look forward

to a successful working relationship in the future!

WISHING YOU AND YOUR FAMILY AND FRIENDS A VERY MERRY CHRISTMAS

We look forward to meeting you on stand n° 15


BIM – KELLER IS READY

I n the last few years, Building Information Modelling has become a central part of conferences in the construction sector. Additionally, there are special conventions which exclusively deal with all aspects related to BIM.

It’s not only the technical work and software packages, but also questions related to legal impacts, necessary changes in project management, communication, responsibilities and many more issues to deal with.

BIM is a method to digitally model and manage a building in all its phases, starting from project development, through the construction phase, to its use. The BIM model does not only include the geometric information (BIM 3D), but, most of the time, also information concerning the construction process (BIM 4D) and the costs (BIM 5D). There are almost no limits to the information content (6D, 7D, etc).The BIM method has its roots in the late 80s, when architects started to connect their geometric building planning with alphanumeric information. Some decades and several software generations later, even complex construction projects like hospitals and industrial buildings can be modelled digitally. Also, big infrastructure projects for road and railway construction are increasingly handled as BIM projects, especially in Scandinavia and England, which has played a pioneering role in BIM. The solutions and products of ground engineering, especially temporary works like excavation pit walls or elements which are less relevant for the future use like foundation elements, are only rarely part of the big BIM models. Nevertheless, Keller Grundbau did its homework to participate in BIM projects as a competent partner. BIM planning is the continuation of our eforts to use new technologies to optimise our own procedures.

Example of application: Visual quality control of pile and jet grouting columns positions

During execution, the real position of all piles and jet grouting columns were measured exactly with GPS and inclinometers. That was documented as a 3D as-built model. After excavation, the surface of the exposed piles and columns was recorded with a 3D scanner. By overlapping the 3D model with the 3D scan you can explicitly evaluate the position accuracy of all elements. The detail shows the overlapped view, where the recorded actual position of the piles is shown in blue and the position of the jet grouting sealing columns in red. In most areas, the scanned surfaces are tightly in front of the piles in the model. In the lower part, where the pile reinforcement was exposed for the connection with the bottom plate and the pile diameter therefore is less, you can clearly see the blue as-built position of the piles.

Design of a complex excavation pit with Autodesk Revit 2017

Alexander Zöhrer

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keller.com

Vienna, Linz, Salzburg, Innsbruck, Dornbirn and Söding/[email protected]

+43 1 892 3526

Global strength

and local focus

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