WAM Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS Engineer: WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT Title: Technical Terms / Chapter-4 / Engineering Specifications / Civil Engineering Works Specification CS01-GENERAL REQUIREMENTS Office : DUBAI Order: Document: MWA_PRO_07/WAM-04-CS01 Rev: OCT/2014 Sheet : 1 of: 17 Federal Electricity & Water Authority CS - CIVIL ENGINEERING WORKS SPECIFICATIONS SPECIFICATIONS FOR WATER TANKS, BUILDINGS AND EXTERNAL WORKS GENERAL INDEX CS-01 GENERAL REQUIREMENTS CS-02 TOPOGRAPHICAL SURVEY CS-03 SOIL INVESTIGATIONS CS-04 DEWATERING CS-05 EARTHWORK CS-06 GENERAL REQUIREMENTS FOR CIVIL/STRUCTURAL WORKS. CS-07 CONCRETE AND REINFORCEMENTS CS-08 CONCRETE WATER STORAGE TANKS CS-09 STRUCTURAL STEEL/ CLADDING WORKS CS-10 PILING WORKS CS-11 PAINTING / GLAZING / TILING CS-12 MASONRY / PLASTERING / SCREED CS-13 JOINERY / METAL WORKS CS-14 SUSPENDED CEILING / PARTITIONS CS-15 DRAINAGE WORKS CS-16 ROADS / PAVEMENTS / EXTERNAL WORKS CS-17 WATER PIPELINE WORKS CS-18 WATER PROOFING AND INSULATION CS-19 SANITARY / KITCHEN INSTALLATION S CS-20 FINISHES / DOOR / WINDOW / FURNITURE SCHEDULES CS-21 DIRECTIONAL DRILLING CS-22 FENCING WORKS CS-23 PRE STRESSED CONCRETE WATER TANK CS-24 MISCELLANEOUS WORKS
Transcript
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Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer: WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
CS01-GENERAL REQUIREMENTS TABLE OF CONTENT 1. CODES AND STANDARDS
1.1 Subsoil Investigations/Excavations/Earthworks 1.2 Concrete Works 1.3 Structural Steelwork 1.4 Painting Works 1.5 Pavements Works 1.6 Miscellaneous Works
2. DESIGN CRITERIA 2.1 Architectural Design 2.2 Structural Design 2.3 Setting out and Construction Tolerances
3. MATERIALS / SUPPLIERS/ MANUFACTURERS 4. SOIL INVESTIGATIONS 5. SITE SURVEY 6. SITE PREPARATION, REQUIREMENTS AND PROJECT LEVELS
6.1 Safety 6.2 Fire Protection 6.3 Work Protection 6.4 Maintenance of Traffic Flows, Temporary Diversions 6.5 Existing Services Protection
6. 6 Scaffolding 7. SITE INSTALLATIONS 8. NOTICE OF OPERATIONS 9. PERMIT TO WORK 10. SIGN BOARDS 11. EARTHWORKS 11.1 Clearing and Grubbing
11.2 Excavations Generally 11.2.1 Open-Cut Excavation 11.2.2 Excavated Materials 11.2.3 Bottom Level of Excavation 11.2.4 Backfilling of Trenches 11.3 Dewatering 11.4 Filling & Reinstatement 11.5 Slips & Settlements 11.6 Compaction and Fill Areas 11.7 Stockpiles and Disposal 11.8 Field Test
WAM
Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
Unless specifically mentioned hereafter, any work or supply of material shall be subjected to the compliance of internationally recognized Standards or Codes, such as BSI, ASTM, DIN or approved equivalent. The Specifications of the CIRIA Guide to concrete construction in the Gulf/GCC region are also applicable. Some Codes and Standards to be followed by Contractor for certain Works are as shown below: 1.1 Subsoil Investigations/Excavations/Earthworks
BS 5930 Code of Practice for Site Investigations BS 1377 Methods of Tests for Soils for Civil Engineering Purposes
1.2 Concrete Works
BS EN 197 – 1, 2011 specifications and conformity criteria for common cements BS 812 Methods for Sampling and Testing of Mineral Aggregates, Sands and Fillers. BS EN 12620:2002+A1:2008 Aggregates for concrete BS 1199/1200 Building Sands from Natural Sources. BS 1881 Methods of Testing Concrete. BS EN 1008:2002 Mixing water for concrete. BS 3712 Building and Construction Sealants. BS 4027- 1996 Specification for Sulphate Resisting Portland cement. BS 4449 Specification for Hot-Rolled Steel Bars for the Reinforcement of Concrete. BS 4482 Steel Wire for the Reinforcement of Concrete. BS 4483 Steel Fabric for the Reinforcement of Concrete. BS 4550 Methods of Testing Cement. BS 4551 Method of Testing Mortar BS EN 934-2:2009 Admixtures for concrete, mortar and grout. BS EN 1992-1-1:2004 Euro code 2. Design of concrete structures. General rules and rules
for buildings BS 8204-2:2003+A2:2011 Screeds, bases and in situ floorings. Concrete wearing surfaces.
Code of practice BS EN ISO 3766:2003 Construction drawings. Simplified representation of concrete
reinforcement 1.3 Structural Steelwork
BS 4-1:2005 Structural steel sections. Specification for hot-rolled sections BS EN 13414-1:2003+A2:2008 Steel wire rope slings. Safety. Slings for general lifting
service BS EN 13000:2010 Cranes. Mobile cranes BS EN 13157:2004+A1:2009 Cranes. Safety. Hand powered cranes BS EN 1011-2:2001 Welding. Recommendations for welding of metallic materials. Arc
welding of ferritic steels BS 5395-4:2011 Code of practice for the design of stairs for limited access BS 5950-2:2001 Structural use of steelwork in building. Specification for materials,
fabrication and erection. Rolled and welded sections
WAM
Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
BS EN ISO 8501-1:2007 Preparation of steel substrates before application of paints and related products. Visual assessment of surface cleanliness. Rust grades and preparation grades of uncoated steel substrates and of steel substrates after overall removal of previous coatings
BS 7668:2004 Weldable structural steels. Hot finished structural hollow sections in weather resistant steels. Specification
ISO 15792-3 2000 Welding consumables - Test methods. Classification testing of positional capacity and root penetration of welding consumables in a fillet weld
BS EN 288 Approval Testing of Welding Procedures - Fusion Welding of Steel. BS EN 10025 Hot Rolled Products of Non-alloy Structural Steel. BS EN 13246 Specification for Tensional Steel Strapping. BS EN 13394 Specification for Non-Metallic Tensional Strapping. BS EN 10029:2010 Hot-rolled steel plates 3 mm thick or above. Tolerances on dimensions
and shape BS EN ISO 12944-5:2007 Paints and varnishes. Corrosion protection of steel structures by
protective paint systems. Protective paint systems BS EN ISO 1461:2009 Hot dip galvanized coatings on fabricated iron and steel articles.
Specifications and test methods 1.4 Painting Works
BS 4800:2011 Schedule of paint colours for building purposes BS 6150:2006 Painting of buildings. Code of practice BS 6949:1991 Specification for bitumen-based coatings for cold application excluding use in
contact with potable water BS 7079 Preparation of Steel Substrates before Application of Paints and Related Products. BS 7664 Specification for Undercoat and Finishing Paints. BS 8202-1:1995 Coatings for fire protection of building elements. Code of practice for the
selection and installation of sprayed mineral coatings BS EN ISO 2064:2000 Metallic and other inorganic coatings. Definitions and conventions
concerning the measurement of thickness BS EN ISO 12944 Code of Practice for Protective Coating of Iron & Steel Structures against
corrosion. 1.5 Pavements Works
BS EN 1340:2003 Concrete kerb units. Requirements and test methods BS 7533 Precast Concrete Paving Blocks.
1.6 Miscellaneous Works
BS 476 Fire Tests on Building Materials and Structures. BS 8215:1991 Code of practice for design and installation of damp-proof courses in
masonry construction PD 6512-3:1987 Use of elements of structural fire protection with particular reference to the recommendations given in BS 5588 'Fire precautions in the design and construction of buildings'. Guide to the fire performance of glass
2. DESIGN CRITERIA
The Contractor shall be responsible for the design, construction and maintenance of the whole of the civil works related to the water storage tanks, pumping stations, pipelines, ancillary structures, roads and other external works. The works also include interface connections with the FEWA’s existing pipelines and tanks wherever mentioned. Designs and details shall fully meet the technical and operational requirements of the mechanical and electrical installations. All designs
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Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
and details must be prepared to comply with the best Engineering practice, the appropriate Standards and Codes of Practice and the requirements of this Specification. No departures from the approved Standards and Specification shall be allowed without the approval of FEWA.The Specification gives the minimum acceptable Standards for the design, workmanship and materials with which the Contractor shall comply. The drawings supplied with the Tender documents are only for guidance and indicate the minimum requirements to be provided by the Contractor. The Contract price shall include the cost of any enlarged structures or modified layout required to meet FEWA's design parameters. Failure of FEWA to comment on the drawings submitted by the Contractor during the construction stage, which show modified arrangements not complying with the Specification, drawings or the design parameters, shall not be accepted as approval of such arrangements. 2.1 Architectural Design The design of the whole work shall be in accordance with the best standards of modern industrial practice. Finishing materials shall be selected so as to match each other and to present ample guarantees of durability. Samples shall be submitted for the FEWA’s approval, as well as selection of colours and textures. The structures as a whole with external works shall give a good aesthetic effect from every angle of look. The perspective drawings with 3D effect shall be prepared by the contractor as required by the Authority. 2.2 Structural Design 2.2 .1 Calculation methods Designs shall be carried out in accordance with accepted FEWA principles and shall meet the requirements of the applicable Standards and Codes of Practice. Any static and dynamic calculation is to be submitted for the FEWA’s approval. When the Contractor uses computerised calculation methods for special kinds of structure, he shall provide a full explanation of such method, should FEWA require it, together with adequate documentation and reference. Structural analysis shall be done with the latest software programmes with new technique and presentation. 2.2. .2 Standards and Codes ( To include all latest amendments)
BS 4449:2005+A2:2009 Steel for the reinforcement of concrete. Weldable reinforcing steel. Bar, coil and decoiled product.
BS ISO 14654:1999 Epoxy-coated steel for the reinforcement of concrete
BS 4483 Specification for steel fabric for reinforcement of concrete
BS 449 The use of structural steel in buildings
BS 2853 The design and testing of steel overhead runway beams
BS 9991:2011 Fire safety in the design, management and use of residential buildings. Code of practice
BS 6262-3:2005 Glazing for buildings. Code of practice for fire, security and wind loading
BS EN 1886:2007 Ventilation for buildings. Air handling units. Mechanical performance
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Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
BS 5821-3:1984, ISO 717-3:1982 Methods for rating the sound insulation in buildings and of building elements.
BS 5950-2:2001 Structural use of steelwork in building. Specification for materials, fabrication and erection. Rolled and welded sections
BS 6180 Code of Practice for protective barriers in and about buildings
BS 6399 Code of Practice for dead and imposed loads
BS 8103 Foundations
BS 8007 The structural use of concrete for retaining aqueous liquids
BS EN 1992-1-1:2004 Eurocode 2. Design of concrete structures. General rules and rules for buildings
BS EN 1991-1-4:2005+A1:2010 Eurocode 1. Actions on structures. General actions. Wind actions
C.P. 118 The structural use of aluminium
BS 7533-12:2006 Pavements constructed with clay, natural stone or concrete pavers. Guide to the structural design of trafficked pavements constructed on a bound base using concrete paving flags and natural stone slabs.( Road A guide to the structural design of pavements Note 29 for new roads).
UNIFIED FACILITIES CRITERIA (UFC) SEISMIC DESIGN FOR BUILDINGS
2.2.3 Structural design principles
a) Foundations shall be so designed to minimize settlements, especially differential settlements, which shall be kept within limits preventing any danger to the construction and the equipment. When necessary, piles of suitable type shall be provided.
b) The requirements related to fire protections shall be taken into consideration. c) The requirements related to seismic force, wind force and other unexpected
forces shall be taken into consideration. 2.2.4 Loadings The design loadings shall conform to the requirements of adopted standards and codes of practice, as well as special Site Conditions and Technical Specifications. The minimum design loading shall comply with the requirements of B.S. 6399. Where known loads exceed those of BS 6399 the higher loading shall be adopted. The minimum earthquake factor shall be taken as 0.15g as per UBC Standard (Uniform Building Code). The revised zone is 2A. In the absence of information covering any special case, the design shall be based on loadings indicated by previous experience or by the results of special tests. 2.3 Setting out and Construction Tolerances The tolerance limits for the permanent finished earthworks will be as follows: Horizontal dimensions will be within +75 mm and -75 mm of the true dimensions shown on the approved drawings. For slopes to embankments or cuttings the horizontal deviation between the top and bottom of the slope will be within +5% and -5% of the true horizontal component of the slope shown or calculated from the approved drawings.Formation levels shall be within 0 mm and -25mm of the
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Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
true levels shown on drawings.Other earthworks levels shall be within +05 mm and -50 mm of the true levels shown on the approved drawings. The contractor is responsible for the accuracy of all setting out and construction tolerances. These shall not be greater than the following : a) Setting out 1 in 3000 b) Structural steel work : 1. Position of first erected column + 10mm 2. Linear Dimensions up to 8m + 10mm From 8 to 15 m + 15mm From 15 to 25 m + 20mm Over 25 m + 25mm 3. Plumb of columns in 30 m height + 15mm 4. Level of base of first erected columns + 5mm 5. Level of beam at junction with column measured from transferred bench mark. + 15mm
6. Level of beam at junction with column measured from transferred bench mark of storey in which beam is located + 10mm 7. Levels of upper or lower surfaces of two or more beams meeting at a column + 6mm 8. Difference in level of ends of a beam : Up to 8 m long + 5mm From 8 to 15 m + 10mm c) In-situ Concrete : Mass Concrete Foundations Dimensions on plan + 50mm Formation level + 50mm Level of upper surface + 25mm Reinforced concrete foundations excepting Plant Foundations : Dimensions in plan 1 in 30 but not exceeding 35mm Formation level + 25mm Level of upper surface + 20mm Elements and components above Foundations including Plant Foundations :
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Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
Position on plan measured from nearest building grid line + 10mm Vertically - Plumb in height of : Up to 0.5 m + 5mm Over 0.5 m and up to 1.5 m + 10mm Over 1.5 m and up to 3.0 m + 15mm Over 3.0 m and up to 30 m + 20mm Cross Section and linear dimensions: Dimensions of beams, slabs, columns & walls. Up to 300 mm + 5mm Over 300 mm and up to 600mm + 10mm Over 600 mm and up to 1.5 m + 15mm Over 1.5 m and up to 3.0 m + 20mm Over 3.0 m and up to 15 m + 30mm Over 15 m and up to 30 m + 40mm d) Level (permissible deviation from designed level with reference to nearest temporary bench mark) : Extensions above Plant Foundations Foundations Length of Elements: Up to 8 m + 10mm + 5mm Over 8m and up to 15m + 15mm + 10mm Over 15m + 20mm + 15mm Overall dimensions of a concrete Framed building - length and width for Dimensions: Up to 15 m + 15mm Over 15 m and up to 30 m + 25mm For each subsequent 30 m + 15mm Height up to 30 m + 20mm e) Items Cast in Position : The permissible deviation of the position of a component fixing or hole cast in shall not exceed + 10mm from its design position. 3. MATERIALS / SUPPLIERS/ MANUFACTURERS
Prior to ordering or delivering any materials or manufactured item to site, the name and address of the Supplier and, , adequate samples, sample schedules and Manufacturer's certificates for all the materials and goods to be used in the works shall be submitted to FEWA/Engineer for approval.
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Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
The Contractor shall make available to their sub-suppliers/ manufacturers all the General and Specific conditions requirements and shall get their acceptance in writing in the form of a letter from all the sub-suppliers/ manufacturers to the effect that they have fully read and understood their implications pertaining to their scope of works and they shall confirm that they have fully satisfied the requirements. The whole of the workmanship, goods and materials incorporated in the works shall be new and of the best quality available and shall be to the approval of FEWA/Engineer. Should FEWA/Engineer discover on the works any materials other than those approved, they may order their removal from site. Removal of these unapproved materials from site is to be done at the expense of Contractor. 4 . SOIL INVESTIGATIONS The Contractor shall employ a specialized geotechnical Company to carryout complete soil investigations at the proposed site, to determine the factors influencing the design and construction such as the type of soil, level of the ground water table, anticipated ground bearing capacity, type of foundations to be adopted and any special measures required to protect the foundations from adverse ground conditions. The soil investigations shall take place immediately and a report shall be submitted in advance of the commencement of works. The Contractor shall only commence the work on Site after reaching agreement with FEWA regarding the interpretation and application of the data contained in the soil investigation report. During the soil investigation the Contractor shall carry out, at each Site, the operations listed in SR-03 as a minimum and shall be provided with latest tests as required by Authority. In case reports and summaries are given by FEWA, it shall be for information only and to provide a guide to the possible conditions existing at the site. The final designs and details must be based on the findings of the Contractor's independent soil investigation. 5 SITE SURVEY
The Contractor shall employ a specialist surveying agency, if required, to carry out topographical survey of the proposed locations and submit topographical drawings with contours marked at 50 centimeter intervals. The required levels of cutting, grade levels, general layout, location of the structures will be finalized based on the topographical drawings. The Contractor shall also carry out all dimensional and setting out checks on the construction items as may be required by the technical sections of interdisciplinary specifications of the contract. Four corners of the plot shall be located at all proposed sites. A 1:100 scale plan shall show all salient features above and below ground . All levels shall be related to an agreed datum. This plan shall be submitted to FEWA and approved prior to the commencement of the works. Two No. Benchmarks based on Admiralty Chart Datum (ACD) shall be established at nearby locations to the proposed sites by using high-tech survey instruments. Site surveys shall be done at all locations before and after earth works are completed and a 1:100 scale plan showing all salient features above and below ground shall be submitted. All levels shall be related to ACD datum. This plan shall be submitted to FEWA prior to the commencement of the works. The Contractor shall be responsible for carrying out complete Site survey at his own expense. After preparation and submittal of his survey, he will be completely
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Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
responsible for any deviation recorded afterwards. All survey shall be based on the topographical drawings or plant general layouts supplied along with the tender drawings. All levels shall be based on ACD (Admiralty Chart Datum). The Easting and Northing co-ordinates shall also be plotted accurately based on (UTM) Universal Transverse Mercator system in accordance with the Global Positioning System (GPS) network. 6. SITE PREPARATION, REQUIREMENTS AND PROJECT LEVELS
Before commencing work at the Sites the Contractor shall submit, for FEWA's approval, proposed finished Site levels, pavement and road levels. Paving, aprons and concrete ground slabs shall be constructed a minimum of 150 mm above the surrounding ground levels. Plinth levels for structures shall not be less than 300 mm above surrounding finished ground levels. The areas within which the Works are to be constructed shall be cleared and graded to the required levels. All debris shall be removed to sites approved by FEWA and the Local Authorities. Low areas shall be raised using approved fill material and high areas shall be reduced in accordance with CS05 – EARTH WORK. 6.1 Safety All Contractor's works shall be performed in accordance with best safe practices for activities to be undertaken during construction.Detailed method statements for each activity to be undertaken shall be prepared by including all proposed safety measures submitted for approval byFEWA/Engineer, which must be obtained prior to the start of the activity concerned.All Contractor's personnel shall be suitably trained to perform activities and in the safe use of all equipment to be operated. 6.2 Fire Protection Adequate precautions shall be taken against fire through all Contractors and Sub- Contractors operations.Construction Practices, including cutting and welding, and protection of adjacent materials during construction shall be in accordance with good standard practices for such work. 6.3 Work Protection The Contractor shall wherever required or directed by FEWA/Engineer cover up and protect the works from the weather and from damage by his own or other workmen performing subsequent operations. He shall provide necessary dust sheets, hoardings, barriers, guardrails etc. and clear away same at completion. 6.4 Maintenance of Traffic Flows, Temporary Diversions Details for maintaining of traffic flow, Temporary road diversions and existing road closures shall subject to approval of FEWA/Engineer and the Federal Traffic Police. No Public or Private facility shall be stopped or interrupted without the written permission of FEWA/Engineer. 6.5 Existing Services Protection Before commencing construction work the Contractor shall locate the routes and identify all services in the Area. Preliminary excavation to locate services shall be by hand tools. The Contractor shall take any and all measures reasonably required by any Public or any Statutory Authority for the support and full protection of all mains, pipes, cables and other apparatus during the progress of the works, and shall construct and provide to the satisfaction of FEWA/Engineer, all works necessary for the prevention of damage or interruption of services.
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Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
The Contractor shall make all arrangements for protecting existing services and for temporarily diverting them to maintain the services without interruption.Existing services, pipes, mains, ducts, etc., exposed in trenches for new work shall be protected in accordance with the requirements of the relevant Authority before trenches are refilled. The Contractor shall lay cables, fittings, specials, etc., under hedges, fences, walls, etc., as necessary.The Contractor shall ensure that no trees are damaged or permanently removed in carrying out the Contract except where directed due to the presence of permanent works and approval is given by the relevant Authority. 6. 6 Scaffolding The Contractor shall provide, erect, maintain, dismantle and clear away at completion proper and adequate scaffolding including that required for Sub-Contractors and Specialists. 7. SITE INSTALLATIONS
All the Constructional Equipment, tools, sheds and other buildings, temporary works and items of whatever description necessary to construct, complete in due time and maintain the whole of the works shall be provided by the Contractor. The Contractor shall arrange for the construction, maintenance and subsequent reinstatement of any temporary access required during the execution of the works at Site. The Contractor may apply to FEWA for approval to use the same for temporary purposes such as temporary offices, site shops and storage of materials. FEWA shall, on application being made, point out the area that can be used for these purposes. Should the Contractor find that the land provided for temporary works is inadequate he shall, forthwith upon such inadequacy becoming apparent, apply to FEWA giving details of his extra requirements. If the Contractor shall require any land outside the area of the Site for the storage or preparation of materials or for other purposes in connection with the Works he shall provide it at his own cost with the concern of local Authorities. Prior to commencing the works on Site, the Contractor shall supply, erect and maintain, at his own expense, a temporary hoarding/fence and gate. The fence shall completely enclose the area of the Works and isolate it from the existing structures if any. The Contractor shall be responsible for the provision of all Site installations, temporary services and facilities, including those for the use of FEWA, as set out in CS02, SITE INSTALLATIONS. The Contractor shall provide water and electricity for the works including that required by the sub-contractors and provide all necessary temporary work.Importing water by tanker and storing on site shall be allowed for by the Contractor.Temporary electricity generating equipment, should this prove necessary, shall be allowed for by the Contractor. 8. NOTICE OF OPERATIONS
Prior to carrying out any operations relating to the Works, the Contractor shall submit, for FEWA's approval, a method statement containing all relevant drawings, details and calculations. This method statement must be submitted in writing sufficiently in advance of the proposed operations. Work shall not commence before written approval has been received from FEWA. No concreting or grouting operation shall be carried out without the written permission of FEWA.
WAM
Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
The Contractor shall obtain a written ‘Permit to Work' (PTW) whenever it is necessary to carry out work in areas where existing plant is operating. Permits shall be obtained before commencing work in any areas containing mechanical plant, electrical plant, pipes or cables and when making connections to any existing services including water, drainage, electricity, gas and telephones. Written permits must also be obtained before any excavations are started. It shall be the responsibility of the Contractor to obtain records relating to any existing services from the relevant authorities. Existing services must be carefully located and exposed, by hand excavation, prior to the main excavations taking place. When existing services lines are encountered in the course of preparing excavations, they shall be carefully maintained and supported in their original location and protected from damage during the execution of the works till the reinstatement of the region. 10. SIGN BOARDS The Contractor shall provide and erect adequate number of sign boards at locations directed by the concerned Department of FEWA/Engineer. The size of the display boards shall be 5000 wide x 3600 deep or as directed by the concerned Department of FEWA. The sign board shall be fixed firmly on designed posts / bracing system in order to resist wind force.The signboards shall carry the names of the project Contractor, FEWA and the Engineer with logos including the particulars of the local site. 11. EARTHWORKS 11.1 Clearing and Grubbing This work shall consist also of clearing and grubbing the area of the work within the limits of the Site and as ordered by FEWA/Engineer of all debris, refuse, vegetation, demolition debris and other deleterious material. If the wastes material suitable for incorporation into or for use on the work, the amount of suitable material shall be replaced by the Contractor at his expense. All material removed by the clearing and grubbing operation shall be transported from the site or otherwise disposed of as specified or directed by FEWA/Engineer. With the exception of areas to be excavated, all depressions made below the ground surface by the removal of rubbish or existing works shall be refilled with suitable material and compacted to the satisfaction of FEWA/Engineer. Grading or excavation operations shall not be started in any areas until clearing and grubbing within the area affected have been completed. Fences, upon or within the limits of the works and not necessary for the construction shall be removed carefully by the Contractor completely or in part as specified or directed. The materials so removed shall be piled neatly and in an acceptable manner or otherwise disposed off as specified or directed by FEWA/Engineer.
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Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
11.2 Excavations Generally Excavations shall be carried out to the widths, lengths and depths described or directed and no unlicensed or indiscriminate digging is permitted. Contractor shall be responsible to excavate the areas near the existing plants by hand shovel without causing any dust pollution. The Contractor shall allow for risk of meeting and having excavating through any sort of material including rock and buried concrete foundations, if any.The Contractor may excavate by any method he considers suitable, subject to the approval and shall allow for the use of any types of machinery most suited for excavations in any location and at any time. The Contractor is to include for all strutting and shoring necessary for the safe execution of the works. Due care shall be taken to protect existing under ground services such as cables or pipes and where required shall be diverted. 11.2.1 Open-Cut Excavation For all fill and cut over 1.00 m in height, sturdy stakes shall be placed at any change of direction of the ground but in all cases at intervals no greater than 30 m as directed by FEWA/Engineer.Survey points, bench marks, boundary stones and the like shall not be removed without FEWA/Engineer written consent. Removed boundary stones and markings shall be stored according to FEWA/Engineer’s instructions. Extra bench marks to be provided by the Contractor shall be furnished with a plate, approximately 25 x 25 cm in size, with the bench mark inscription painted in black letters on a light background with clearly legible weatherproof oil paint. Permanent bench marks shall be provided on brass plate fixed on concrete pedestal . Excavations in sand shall be to a slope of 1:3, one vertical to three horizontal. If any permanent slope is to be kept in the sand it shall be stabilized by one of the following means, - 150 mm of compacted gatch (Road base material ) - Cement/sand mixture - Bituminous/cement mixture - Precast concrete paving tiles Bottom and slopes of open-cut excavations on which concrete is to be placed shall be finished exactly according to the established lines and slopes. To avoid loosening of the soil, heavy equipment such as bulldozers or power shovels shall not operate within 10 cm of the final lines of the excavation bottom. The last 10 cm shall be excavated by means of hand tools. 11.2.2 Excavated Materials During the construction of the works, the Contractor may use materials from the excavation if approved by the Engineer. Other excavated material shall be backfilled where required or deposited where directed anywhere on site. The Contractor shall remove the surplus materials from the site. The Contractor shall at all times keep the site free from all surplus materials, rubbish and offensive matter. 11.2.3 Bottom Level of Excavation The bottom of all excavated areas shall be trimmed, leveled and well rammed. The bottom level of excavations or foundations shall be inspected and approved before foundations are constructed.
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Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
11.2.4 Backfilling of Trenches Trench refilling shall fill shall be compacted in layers not exceeding 200 mm thick, each layer being well compacted to 95% of its maximum dry density by hand with iron rammers weighing not less than 5 kg, until the trench has been filled to a height of 300 mm above the top of the materials e.g. cables/ducts etc. The remainder of the trench shall then be refilled in compacted layers not exceeding 200 mm in thickness, each layer being well compacted with power rammers, vibrating plate compactors or other mechanical means until the ground is thoroughly consolidated up to the required level for surface reinstatement. Where cover to materials e.g. cables/ducts is less than 400 mm, or where ordered by FEWA/Engineer, protection in the form of concrete encasing shall be provided according to an approved drawing or as ordered by FEWA/Engineer. 11.3 Dewatering The excavated surfaces shall be kept dry and clean by pumping or any other method deemed necessary and approved by the Engineer. Water from such dewatering shall be properly drained away from the site or disposed off by tankers. The Contractor in his tender shall cover the cost of pumping or dewatering. No concrete, masonry brickwork or other materials shall be placed or built until the surface is properly drained. Where swamps, bogs or other similar wet areas have to be traversed by the works, they shall be drained as directed by FEWA/Engineer according to the materials and conditions encountered. 11.4 Filling & Reinstatement Filling for trenches, excavations and leveling of the site shall be deposited in layers not exceeding 225mm in thickness each layer watered well and rammed by mechanical rammers, to consolidate in 95 % of the maximum dry density. Where excavations, whether in rock or other material, are made to a greater depth than required or as instructed by the Engineer, the intervening space shall be brought up to the proper level in plain concrete of Grade C-20 Any ground encountered during the excavations which is observed not suitable to bear the expected loads which will be imposed on it, shall be excavated and replaced with concrete of Grade C-20. Prior to the formation of embankments, fills, etc., any unsuitable materials occurring on the site shall be removed to such depths and widths as may be directed by FEWA/Engineer and approved excavations shall be properly backfilled with suitable and approved excavated materials and shall be deposited and compacted to the satisfaction of FEWA/Engineer. Similarly, soft or weak spots encountered will be removed and, as with any voids, will be backfilled as specified. 11.5 Slips & Settlements Proper strutting, sheeting and bracing, including re-arrangement of the installations when necessary, protection of slopes, methods of excavation to reduce risk of slides, etc., shall be for the responsibility of the Contractor. Should any slips occur in the excavations, banks or filling during the execution of the works or during the period of maintenance from any cause whatsoever, the contractor shall execute the necessary remedial work in such manner and form and with such materials and/or as approved by
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Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
the Engineer. The Contractor shall make good all settlement of filling that may occur up to the end of the period of maintenance. Where the nature of the soil gives reason to fear any drifting, initial excavation operations shall be carried out with special care. Excavation shall not be carried out below existing building foundations, if any, until shoring to be performed by the Contractor has been completed. All existing structures, foundations, pipes and cables, if any, which are to be incorporated into the final work shall be adequately protected or replaced by the Contractor. 11.6 Compaction and Fill Areas In areas where excavated or imported material is to be used as compacted fill, the contractor will be required to achieve a density of not less than 95% of the dry density for the excavated or imported material. The Contractor shall maintain all equipment, for determination and checking of the compact density at the site and the tests shall be carried out in the presence of the FEWA/Engineer. Foundations and structures shall be backfilled with approved material compacted in layers by suitable equipment until maximum density has been obtained to the satisfaction of FEWA/Engineer. Compacting shall be carried out with special care by means of pneumatic or mechanical tampers of a type previously approved by FEWA/Engineer to avoid damage to structures. Areas to be backfilled will be prepared so as to obtain a soil density at least equal to 95 percent of Modified Proctor test (ASTM D 1557). The thickness of loose fill layers shall not exceed 300 mm unless the Contractor proves to the satisfaction by test beds that the equipment and method of compaction exceeds the required density. Surfaces receiving fill layers shall, if smooth, be previously scarified to obtain a good key between the new fill layer and the sub grade. Fill shall not be deposited under water without FEWA/Engineer permission. This permission may be granted to place rock fill by random dumping in areas where the depth of water is greater than 30 cm but the methods and quality of the fill material shall be subject to approval and when the fill level is 50 cm above the water surface it shall be compacted until there is no discernible movement under the equipment used for placing or compacting fill. Thereafter, normal backfilling and compaction shall be resumed. 11.7 Stockpiles and Disposal Excavation material from the works selected by FEWA/Engineer for use shall be placed in its final position, if possible, or otherwise may be stockpiled or deposited on site as directed by FEWA/Engineer. Only the stockpiling of rock, gravel and other non-cohesive materials to be used for permanent work will be permitted.
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Client: FEDERAL ELECTRICITY AND WATER AUTHORITY (FEWA) Project: STANDARD SPECIFICATIONS FOR WATER WORKS
Engineer WATER DIRECTORATE - ASSET MANAGEMENT DEPARTMENT
In no case shall the stockpiling of silt or disintegrated rock to be used in structural fills be permitted. Spoil unfit for re-use shall be removed by the Contractor to sites approved by FEWA/Engineer. Contractor shall trim and form the edges of soil to profiles and levels as directed by FEWA / Engineer. He shall also maintain without interruption the flow of water courses affected by the disposal of spoil materials. The placing of materials within the waste areas shall be made in layers not exceeding 50 cm in thickness in order to obtain an appreciable degree of compaction by means of the transportation equipment. All traffic towards or from the waste areas shall be continuously directed and changed for the total covering of the surface of such areas in order to take advantage of the weight of vehicles for compaction. Waste areas shall be located in those places where, they do not interfere either with the natural flow of water or with future structures and where they can not impair the general appearance of the completed structures or impede access to the different structures. 11.8 Field Test The control of working and tests operations will be carried out by FEWA/Engineer with the full assistance of the Contractor. The Contractor will prepare sheets for statistical analysis of the field and laboratory tests as required in accordance with the respective ASTM or BS requirements. Field density tests in accordance with BS 1377 will be required to be carried out by the Contractor at each successive layer of fill at a sampling rate determined by FEWA/Engineer.
