Volume V of V

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NMDC LIMITEDHYDERABAD

KUMARASWAMY IRON ORE PROJECT

BELLARY DIST - KARNATAKA

TENDER DOCUMENT

FOR

VOLUME V OF V

MECON LIMITED

BANGALORE

MEC/01/Q6DH/NMDC-KIOP/PKG-II/TD REV. 0 JANUARY 2010

PACKAGE - II

DOWNHILL CONVEYOR SYSTEM


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PACKAGE NO II DOWN HILL CONVEYOR SYSTEM

CONTENTS

VOLUME I of V

Chapter

NoDescription

1. Check list

2. Notice Inviting Tender (NIT)

3. Instructions to Tenderers (ITT)

4. General Conditions of Contract (GCC)

5. Special Conditions of Contract (SCC)6. Erection Conditions Of Contract (ECC)

VOLUME II of V

1.Preamble, Summary of Prices, Price for exemptions / variationsand Price Format

VOLUME III of V

ChapterNo

Description

A Brief on the Project and Intent Of Tender

B General technical conditions

C General site information

D Scope of work and battery limit

E Performance guarantee and warranty

F Surface preparation and painting

G Quality assurance, inspection and testing

H Construction, erection, testing and commissioning

I Engineering services

J Project management services

K Site services

L List of Tender Drawings

Part/1 - Documents/ drawings to be submitted along with the

tender

M

Part/2 Questionnaire and design data sheets to be filled andsubmitted along with the tender


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PACKAGE NO II DOWN HILL CONVEYOR SYSTEM

N Documents /drawings to be submitted by successful Tenderer

O Spares, Special tools & Tackles

P List of Preferred makes of equipment

Q1 Technical specification Mechanical

Q2 Technical specification Environmental

Enclosures: -

1. Tender drawings as per the list under chapter-L2. Specimen QAP format for Structural & Mechanical equipment3. Specimen QAP format for Electrical equipment4. Specimen Inspection call format

VOLUME IV of V

Chapter

NoDescription

Q3 Technical specification Electrical

Q4 Technical specification Automation and ControlQ5 Technical specification Plant Communication System

VOLUME V of V

ChapterNo

Description

Q6 Technical specification Civil

Q7 Technical specification Structural

Q8 Technical specification Hydro Engineering

Q9 Technical specification Fire Detection and SuppressionSystem for Down Hill Conveyor

Q10 Technical specification General Layout, Roads and Fire

Fighting

Enclosures:- One Compact disc containing soft copy of the following:

1. Soft copy of Questionnaire and design data sheet Chapter-M (Part-2 of 2)2. Soil investigation report (for reference only)

3. Waste Dump Locations - Sketch dated 14.09.07


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PACKAGE NO - II VOLUME - V of V

CHAPTER NO. Q6 Page 1 of 194

MEC/01/Q6DH/NMDC-KIOP/PKG-II/TD Rev. 0

2010, MECON Limited. All rights reserved.

CHAPTER Q6

TECHNICAL SPECIFICATION CIVIL

CONTENTS

Section No. DescriptionSection - I General & Scope of Work

Section - II Architectural & Civil DesignParameters

Section - III Detail Specification for Civil

Construction Works

Section - IV Norms of Cement Consumption

Section - V Dimensional Tolerances

Section VI Method of Measurement

Section VII Safety Code


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SECTION I : GENERAL & SCOPE OF WORK

1.0 GENERAL

1.1 The scope of this tender includes analysis, design, detailed

engineering, preparation of construction drawings, bar bendingschedules and submission of design calculations andconstruction drawings for approval of the Owner/ Consultant,supplying of all material, testing of all materials as per

specifications/ BIS codes and labour and construction of thefacilities as per the provisions of this specification,

commissioning and handing over all facilities to the client.

2.0 SCOPE OF WORK

2.1 The following / Buildings facilities are envisaged:

Sl.No.

Description Remarks

1.RCC trestle foundations / foundation forshort post for Conveyor No: 718.

2.Transfer House No:1 Columnfoundations & with 200mm thick RCCfloors on steel beams.

3.RCC trestle foundations / foundation for

short post for Conveyor No: 719.

4.RCC Storage Silo of 1000 t Capacity withstructural roof.

5.

Tail/Drive house column foundations and

foundation for drive platform with RCCfloors.

6.Transfer House No: 2 Columnfoundations & with 200mm thick RCC

floors on steel beams.

7.Transfer House No: 2A Columnfoundations & with 200mm thick RCCfloors on steel beams.

8.Parking/Maintenance station fortraveling trolley (PS-1) Column

foundations.

9.RCC Trestle foundations for ConveyorNo: 721.

See clauseNo. 3.0

Givenbelow for

descriptionof the

facility /

Building.


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10.Down hill Conveyor No: 723 with RCC,foundations, trestles with beam forsupporting steel gantry.

11.RCC Trestle foundations for ConveyorNo: 727.

12.Parking/Maintenance station fortraveling trolley (PS-2) Columnfoundations.

13. Transfer House No: 3 Columnfoundations & with 200mm thick RCCfloors on steel beams.



15.Transfer House No: 5 Columnfoundations & with 200mm thick RCCfloors on steel beams.

16.

Transfer Station Column foundations &with 200mm thick RCC floors on steel

beams.



18.RCC Trestle foundations for ConveyorNo: 727-1.

19.RCC Trestle foundations for ConveyorNo: 727-2.

20.

Sub-station at tail end of down hill

conveyor with Office room, VFD room,Switchgear room, Pump house, Shift In

charge room, Control room, Cable cellar,battery room, etc.

21.

Sub-station near TH-5 with Office room,

VFD room, Switchgear room, Cablecellar, battery room, etc.

22.

Sub-station near TH-3 with VFD room

for Belt Feeder and other panels as perrequirement.


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23.

The following Service Roads includingculverts, road side drains, retainingwalls, necessary slope protectionmeasures, etc.

a) Approach road to TH1, Silo area, Tail/ drive house of Down Hill Conveyor, TH-

2, TH-2A, PS-1 and Electrical, controlcum office building from the approachroad proposed for Secondary CrushingPlant.

b) Approach road to PS-2 and take-uparea of down hill conveyorc) Approach road to belt lay down areaat two locations

d) Approach road to TH-3 from theexisting kachcha road.

e)Approach road to TH-4, TH-5, TH-6 &

electrical room near TH-5 from the roadsavailable already.

24.Belt Lay Down Areas (Area of300mx10m) At two places.

25.

Micro leveling and area developmentaround Transfer House No: 1, 2, 2A, 3,4, 5, 6, Tail / drive house, Silo,

Parking/Maintenance shed PS-1 & 2,etc., including building aprons, stormwater drain, approach road, culverts,

retaining walls, necessary slopeprotection measures etc.

26. Parking Facility

27.

Laying and fixing of MS / GI water pipeline from the proposed fire water

reservoir / hill top reservoir to variousfacilities proposed under package-IIincluding foundations and anchor blocks.

2.2 Based on the conceptual drawings and the basic design

parameters defined in this tender, the tenderer shallprepare layouts, detailed architectural drawings, design

criteria, analysis and design calculations, civil shuttering andreinforcement drawings, bar bending schedules. Approval of

the Consultant shall be taken at each of the stages before the


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construction work is taken-up. Work shall be executed inaccordance with approved drawings, issued for construction.

2.3 The civil construction drawings, in AutoCAD, shall take care ofall the technological requirements. Any revision required for

the technological requirements shall be automaticallyincorporated in the civil drawings and got approved again.

2.4 Design criteria, civil analysis and design, architectural

drawings and constructions drawings shall be got approved instages well in advance to match with the sequence of

execution.

2.5 Contractor shall submit ten sets of design calculationsdocuments and Drawings for approval of consultant.

2.6 Only latest revisions of the drawings shall be followed and

all old revisions shall be clearly marked SUPERCEDED andkept separately or destroyed as directed by Consultant.

2.7 The tenderer shall acquaint himself of the site related data,

conduct additional investigation as may be essential andrequired for efficient working of the facility as per soundengineering practice, which will be deemed to be a part of the

scope even though not explicitly defined in the tender.Tenderer is free to refer to site survey and soil investigationdata available with the Owner / Consultant which will be made

available to the tenderer on request. No claim shall beentertained in case of deviations from the supplied data.

2.8 Along with the tender the tenderer will submit one set of

drawings showing the area he proposes in each of the area,based on the concept drawings and the architectural and

civil design parameters.

2.9 Provision for building drains, apron, sanitary & water supplysystem, statutory requirements as per factories act will also

form a part of this tender.


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3.0 GENERAL DESCRIPTION OF BUILDINGS AND FACILITIES

3.1 Foundations for trestle supports for conveyors:

The foundations for structural trestle supports for all

conveyors shall be constructed in reinforced cement concreteduly taking into account wind loads, earthquake load,equipment loads, etc. The trestle foundations that are proneto undermining and erosion of topsoil due to rainwater shall

be protected by appropriate methods like cut-off walls, catchdrains and stone pitching. Locating the trestle foundations in

the watercourses, rivulets and other water bodies shall beavoided. In cases where the trestle foundations are to belocated on sloping hilly regions, the foundations shall beplaced on stable and firm soil stratum. The trestle foundations

shall be constructed on suitable and adequate capacity piles incases where such foundation system is to be adopted due to

engineering properties of existing soil. The down hill conveyorNo.723 shall be provided with RCC trestles up to a height of12m (For trestle heights above 12m structural trestles shall beconsidered.) with RCC foundations and RCC supporting beam

for the gallery.

3.2 Transfer Houses:

The transfer houses shall be in structural steel with CGIsheeting and translucent cladding. The translucent sheeting

shall be about 15% of the roofing and side cladding area. Thefoundations for the structural columns shall be in RCC. Floorsshall be of RCC. The floors of the transfer houses shall have

adequate slope to facilitate cleaning of accumulated muck

water washing. Granolithic floor of sufficient thickness(min.200) with non-metallic floor hardener shall be provided.

3.3 RCC Storage Silo (1000t (effective storage) Capacity):

A RCC Silo of 1000 t capacity (effective storage) is proposed

for storing graded iron ore. The RCC silo shall be designed forthe dead load of iron ore material. Insert plates on the wallsand hopper bottom shall be provided for welding wear

resistant liners (for specification of liners refer relevantchapters). Super structure of RCC silo shall be of structural

design. Mat foundation shall be provided for the RCC silo.Foundations for belt feeders shall be designed and constructed


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considering the dynamic forces as per manufacturers loaddata. Suitable opening shall be provided in the silo wall foraccommodating the belt feeder, approach to belt feeder

platform from the structural staircase, etc.

3.4 Open Excavation for single flight down hill conveyor:

The down hill conveyor shall be taken through open earthencuts whenever the ground level is higher than the conveyor

top level. The sides of the open cut surfaces shall be stableand flat. The conveyor shall be supported on RCC pedestal and

on suitable foundation. Adequate surface storm waterdrainage arrangement shall be provided on either side ofconveyor running through earth cuts. RCC box culvert ofadequate section shall be provided to drain off higher reaches

of the hill.

3.5 Office Building / Electrical Room / MCC Room / ControlRoom:

These buildings shall be in RCC frame construction with

masonry infill walls. The carpet area of single/Double storyoffice shall be arrived based on technical requirements coveredin relevant chapters and as per relevant BIS norms. Plumbing

and sanitary fittings, bathroom, Indian and European typewater closets, septic tank and soaking pit shall be designedand provided for 15 male members.

3.6 Service Road:

A service road of 10 m formation width, 1.5m shoulder on

either side and 4m WBM carriage way, with bitumen carpeting,shall be designed for axle load of 10 t. The road shall bedesigned as far as possible to run in cutting avoiding filling.

RCC retaining wall of adequate cross section shall be designedin cases where road is required to pass over filling. The road

shall be designed for a gradient of 1 in 20. The road shall bedesigned proving adequate turning radius at curves and

bends. Adequate super elevation and extra width shall beprovided at curves and bends for vehicular speed of 30 KMPH.Overtaking sight distances, stopping sight distances, hairpinbends and other geometric design elements shall be designed

and provided for as per relevant IRC codes of practice forroads in Hilly Regions. Double rail (W-W section) Metal Crash


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barrier, Cat-eyes kilometer stones, informatory and warningsigns with suitable radium coating shall be provided atappropriate locations as per IRC norms. Suitable drainage

facilities like roadside drains catch pits RCC box culverts shallbe provided.

3.7 Area Development:

The areas around Transfer Houses, Silo, tail/drive house,

office building/MCC / Control / Electrical Room shall be microleveled and suitable storm water drains to drain off rainwatershall be designed and provided. RCC apron of 750mm wideshall be provided around all buildings and facilities along withbuilding drain, which shall be connected to surface storm

water drain. The storm water drain / channel shall beconnected to a near by valley area for discharging stormwater.

3.8 Parking Facility:

Suitable vehicle parking facility for 2 no. of four-wheelervehicles and minimum of 10 no. of two-wheeler vehicles shall

be provided at all Transfer Houses, office building/MCC /Electric / Control Room and RCC Silo areas. The parking shallbe designed in structural steel super structure with CGIsheeting and RCC foundation. The parking area shall be

constructed in WBM construction of adequate thickness withbitumen carpeting.

3.9 The tenderer shall consider the following finishes/ fixtures forfacilities covered under the scope:

I. Schedule of finishes:Sl.No.

AREA DESCRIPTION OF FINISHES

1. Plastering and White / colourwash a) Inside

b) Out side

c) Ceiling

12mm thk. in CM (1:6)+ 2coats OBD over priming coat.

15mm thk. in CM (1:6) +cement based approved colour

wash over priming coat.

6mm thk. In CM (1:3) + 3coats of white wash.


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2. Flooring and skirtinga) Hall and in-charge room

b) Toileti) Floor

ii) Dado

20mm thk. Grey cementTerrazo tiles and 100mm

skirting

Ceramic tile of approved

shade.

White glazed tile for 1500mm

high.

3. Roof water proofing treatment. Polymeric water proofing

membrane over screed (75mmave. thk.)

II. Schedule of plumbing sanitary fitting / fixtures

Toilet:

a) Closet: Indian type vitreous water closet of 580x440mm sizeand approved colour. European type vitreous water closet of

580x440mm size and height of 400mm, and approved colourincluding 15lit, PVC cistern etc.

b) Urinal: White vitreous china urinal of size 430x260x350mm

including half round drain channel, 15lit, PVC cistern etc.,

c) Wash basin: white vitreous chaina wash basin of size630x450mm, including 600X600 mirror, a pair of 15mm C.P.

brass pillar taps, angle cock, bottle trap, soap container,600mm Tower rail, etc.,

d) Min. 1000 lit. Capacity HDPE overhead water tank with32mm dia GI inlet and overflow pipes. 25mm dia GI outlet

pipes with distribution pipes of 20mm & 15mm GI pipesincluding all accessories like 32mm,25mm gunmetal gatevalve with CI wheel.

e) 15mm CP brass bib cock & stop cock including allaccessories.


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III. Schedule of Doors, Windows & Ventilators.

a) Door

D1 - 1000X2100 35 mm commercial ply flush door

including 100X75mm 2nd class teak wood doorframe, with 2 coats of enamel paint over a coat ofprimer.

D2 - 900X2100 35 mm commercial ply flush door

including 100X75mm 2nd

class teak wooddoorframe, with 2 coatsof enamel paint over a coat of primer.

D3 - 800X2100 35 mm commercial ply flush doorincluding 100X75mm 2nd class teak wood

doorframe, with 2 coats of enamel paint over acoat of primer.

b) Windows - 1500X1200 Glazed wooden window in 2ndclass

teak wood including two coats of enamel paintingover coat of primer painting.

c) Ventilator - 600 X450 wooden ventilator in 2nd class teakwood including glazed louvers and including twocoats of enamel painting over a coat of primer

painting.

d) Exhaust Fan -300 dia. Electric exhaust fan with all necessary

fixtures.


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SECTION II : ARCHITECTURAL AND CIVIL DESIGNPARAMETERS

1.0 GENERAL

1.1 This part of the specification defines the Architecturalrequirements and design parameters for analysis and design ofthe civil buildings/facilities.

2.0 ARCHITECTURAL DESIGN REQUIREMENTS

2.1 Architectural design shall be in accordance with the followingreferenced publications:

a) National Building code of Indiab) State Government Factories Act.c) Local Municipality or any other authoritys Byelaws as

applicable.

2.2 Spatial requirements:

2.2.1 Spatial requirements inside a building shall be based on theactivities to be performed in the building, equipment layout,etc.

2.2.2 The objective of spatial arrangement is to satisfy functionalrequirements and physical comfort and safety regulations aswell as aesthetics which has significant role in creating afavourable working and living conditions.

2.2.3 However the following are the limiting sizes, dimensions forvarious purposes, which are to be adhered to:

AMinimum size of anyhabitable room

9 sq. m with minimumdimension not less than 2.5m

BMinimum height of anyhabitable room

3m, which may be reduced to2.75m for air-conditioned

areas.

C

Maximum height of any

habitable room

3. 6 m


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DScale of accommodationfor Industrial work spaces

14 cum per occupant. Minimumclear height of such workspacesshall be 3.6m.

2.3 Day lighting and Natural ventilation

2.3.1 Established level of illumination shall be maintained for allparts of the buildings by means of windows, skylights, etc.Established level of ventilation in terms of air changes perhour shall be maintained for all spaces. References shall bemade to National Building Code & Factories Act in this regard.Natural ventilation shall be supplemented by mechanical orelectrical means of ventilation in all human occupied areas

2.4 Safety requirements

2.4.1 Safety from fire and like emergencies shall be taken intoaccount in building/shed design. Every building/ shed meantfor human occupancy shall be provided with fire exits sufficient

to permit safe escape of occupants in case of emergency.

2.4.2 The exits shall be in terms of doorway, corridors, passagewaysto internal/ external staircase or to areas having access tooutside.

2.5 Building services

2.5.1 Water supply, distribution, drainage and sanitary services shallbe provided for all buildings/ sheds as essential services.

2.5.2 Areas of control room, spaces housing equipments, machinery,panels, offices, etc., which require special conditionedenvironment, shall be provided with forced ventilation/ airconditioning.

2.6 Aesthetics

2.6.1 Apart from the fulfillment of functional & safety requirement,aesthetic requirement of the building shall be given dueimportance in the design. Elements like canopies, Overhangs,Shades, Gutters, Door/window/ ventilator composition,

external wall location with respect to columns, colour scheme,grooves in plaster, etc. shall be considered as contributory


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elements to aesthetics and these shall be designed judiciously.

2.7 Structural and construction elements

2.7.1 Type of structure and construction shall be as per technicalrequirements. However the following may be followed asguidelines:

Building Type of structure andconstruction

Transfer Houses RCC foundation, RCC floors onstructural beams. Structural Steelsuper structure with CGI /Translucent Sheeting.

Trestle foundations RCC.

Down hill conveyor Structural trestles for the structuralgallery.

Office building, Electricroom, MCC room.

RCC framed structure withmasonry infill walls.

Service Road 10 wide formation; 1.5m Shoulder;4m WBM carriage way with bitumencarpeting.

2.8 Terrace Levels

2.8.1 The terrace levels shall be fixed based on the topography ofthe area and the filling/ cutting requirements as well as roadgradients. In general terrace levels shall be 300mm below theroad top level.

2.8.2 In areas of rock outcrops/ cutting the surface shall be so

chiselled so as to be aesthetically pleasing.

2.9 Finished floor levels

2.9.1 In general, finished floor levels of the building, sheds shall bedetermined with respect to top of approach road or pavement.Generally FFL shall be 600mm above terrace levels near thebuilding or as indicated in the drawings.


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2.10 Steps/ Ramps

2.10.1 Steps/ ramps shall be provided for access to the building/sheds for pedestrian/ vehicular, equipment entry. Minimum1000 mm wide platform shall be provided in between entrancedoor and steps/ ramps. Following dimensions of steps/ rampsshall be adhered to:

ATread 250 mm minimum

BRiser 175 mm maximum

CSlope of ramp Not steeper than 1:6

DMaximum number of steps inone flight

12 Nos.

2.11 Walls

2.11.1 Following shall be adhered to for wall material and thickness:

AExternal & Load bearingwalls

230 mm brick masonry or200 mm CC block masonry.

BFire wall (aroundtransformers as specified)

345mm brick masonry or300mm CC block masonryor 225mm RCC wall.

CInternal partition wall 115mm brick masonry or

100 mm CC block masonry.

Note: 1. 115/100 mm thick Internal partition walls shall beprovided with 75 mm thick horizontal RCC bandsat every 5thcourse.

2. Wherever conduits or pipes are required to beconcealed within partition wall, or boxes are to beprovided, the wall thickness shall be increasedsuitably.

2.12 Doors: Doors shall be provided for access, security and safetyat all entry & exit of rooms, functional areas and buildings.Sizes of the doors shall be determined on the basis of thefollowing schedule.


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A Equipment, Panel area Size of maximum

equipment includingpacking.

B Other areas Volume of movementthrough the door.

C Minimum entrance door size 1500 mm x 2100 mm (wallopening size)

D WC, Bath cubicle door(min) 750 mm x 2100 mm (wallopening size)

E Minimum size of other doors 1000 mm x 2100 mm (wallopening size)

Note: 1. Normally entrance doors shall be providedcovering full width of the entrance lobby. In thatcase the door shall be of composite typeconsisting of openable shutters & fixed portions.

2. Rolling shutters shall be provided wherever arearequirement of openable shutters exceed 2500 x2500 mm.

3. Mechanically operated rolling shutters shall beprovided for all opening sizes.

2.13 Windows/ Ventilators

2.13.1 Windows/ Ventilators shall be provided in all areas for naturallighting, ventilation and visibility at working level.

2.13.2 For the purposes of ventilation, total openable areas of the

windows/ ventilators shall be as per Factory act, subject to aminimum of 15% of the floor area to be ventilated. However,for non-process Control Room, security block, Gate Housesand in office areas, etc. where visibility from inside is of primeimportance, increased window areas shall be provided. Areasaccommodating panels/ equipments shall be normally providedwith ventilators at high level for unobstructed distribution oflighting.

2.13.3 Issue counters wherever required shall be provided withseparate sliding/ hinged shutters and peep holes in the glass

at appropriate height.


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2.13.4 For height more that 4000 mm additional window/ventilators shall also be provided to ensure minimumillumination & ventilation at every level of the building/ shed.In case of walkway/ gangway, etc. windows/ ventilators atworking levels shall be provided in the same manner as atworking area.

2.13.5 Wherever due to limitation of external wall area or any otherreasons, stipulated area of Windows/ Ventilators cannot beprovided, suitable mechanical/ electrical devices shall beprovided.

2.13.6 Fly mesh shutters shall be provided for Pantry & Dining hallWindows/ Ventilators.

2.14 Canopy/ Overhang

2.14.1 Canopy/ overhangs shall be provided at all entries and existfor rain & sun protection, accentuation of entry/ exit and

movement from or to parked vehicle. Size of the overhangshall be decided based on the aesthetics of the building/shed subjected to minimum 1200 mm.

2.15 Shading devices shall be provided over all windows, openableventilators for rain & sun protection. These devices shall bein form of horizontal projections, vertical projected fins orcombination of both as per building faade treatment.Minimum projection shall be 600 mm. The top surface of theshading devices shall be finished with cement plaster mixedwith water proofing compound (laid to slope) and shall be

provided with GI/PVC spouts. Roof projection shall beprovided wherever feasible for at least 750 mm.

2.16 Parapets shall be minimum 300 mm high for non-approachable roof. In case of future expansion, GI/ MSrailing may be provided.

2.17 PVC Rain water pipes, spouts shall be provided for roof waterdrainage. Number of rain water pipes shall be decided on thebasis of roof area., slope and rainfall intensity. Rain waterpipes shall be provided with bottom shoes and drain

channels leading to surface drains.


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2.18 Entrance lobby & corridors

2.18.1 Entrance lobby shall be provided as a common entrance forsuch buildings/sheds accommodating separate or similarfunctional spaces integrated together. Individual entries tosuch functional spaces shall be from this lobby by means ofpassages/ corridors. Apart from common entry lobby, separateindependent entries to these functional spaces shall beprovided if required.

2.18.2 Passages/ corridors shall be provided to integrate variousspaces. Width of the passages/ corridors shall be as perfollowing schedule:

A Singly loaded passage/corridor

Minimum 1200 mm

B Doubly loaded passage/corridor

Minimum 1800 mm

C Stores, etc. As per movement

requirements

2.19 Air lock lobby: Air lock lobby shall be provided for all entry andexit of air-conditioned space. However air lock lobby may beavoided in case of small air conditioned habitable spaces.

2.20 Emergency exits: Emergency exits shall be provided for all thebuilding/ sheds as per Factory acts. Emergency exits forindividual functional spaces such as console area, cable cellar,switchgear rooms shall also be provided. Emergency exits shallbe located in such a manner that the escape route is direct,

unobstructed and without passing through any other functionareas to safe area. Corridor/ staircases shall be provided asescape route to the emergency exits.

2.21 False ceiling: false ceiling shall be provided for the followingpurposes wherever required.

ATo reduce the volume and hide ducting etc. for airconditioned space.

BTo maintain acoustic level inside any space

CTo reduce habitable room, corridor, lobby, toilet heightslocated in high ceiling building/ shed to minimum 3000 mm


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2.22 False Flooring/ cavity floor: False floor/ cavity floor shall beprovided to accommodate under floor cabling ininstrumentation console, rack, UPS room, etc.

2.23 Plinth protection: Plinth protection shall be provided to allbuildings/ sheds with minimum 1000 mm width and slopedtowards drain around the building.

3.0 ARCHITECTURAL FINISHES

3.1 All architectural finishes shall be as per specifications,standards and approved list of vendors.

3.2 Colour scheme for all architectural items shall be asapproved by Consultant/ Owner.

3.3 All building elements i.e., floor wall, ceiling, roof, doors, &windows, etc. shall be provided with architectural finishes asshown in the building drawings. Wherever the finishes are

not mentioned, the following finishes shall be followed:

3.3.1 Floor finish

Sl.No.

Building/ room/ area Finish

A Control rooms, UPS roometc.

False flooring

B Entrance, Conference rooms,Office rooms, Corridors, etc.

Marble stone/ Vitrifiedceramic tile (mirror polish)

C Change rooms,

Documentation rooms, etc.

Terrazzo tiles.

D Equipment rooms, servicerooms, pump houses, etc.

Heavy duty cementconcrete flooring

E Stores Granolithic floors.

F Toilets Antiskid ceramic tiles andmatching ceramic tile dado(2.1m ht.)

Note: 1. Skirting shall be provided in all areas. Cementplaster skirting shall be provided in areas havingcement concrete granolithic/ heavy-duty cement

concrete flooring. For other areas, skirting shall beof same material as that of the floor. Skirting shall


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be of 125mm ht. Minimum for cement skirting andterrazzo tiles and 100 mm for ceramic tiles.

2. Panel dividers shall be provided in cement concreteflooring.

3.3.2 Wall finishes & roof treatment.

Sl. No. Surface Finish

A. Internal finishes of all buildings

1 Control room, Office room,Conference room, Labs,entrance foyer, etc.

Plastic emulsion paint over12mm thick cementplaster.

2. Change rooms,documentation rooms,stores, Panel rooms, etc..

Acrylic washable distemperover cement plaster

B. Exterior finishes

1 Admin buildings Exterior emulsion paint.

2 All other buildings Waterproof cement paint.

C. Roof treatment

1 Flat roofs Polymeric water proofingmembrane over screed(average 75mm th.)

2. Slopped roofs Mangalore pattern tilesover water proof cementplastering.

4.0 ANALYSIS & DESIGN

4.1 Analysis and design of buildings/facilities shall be done as pergood engineering practices by experienced personnel. All datarequired for checking of analysis and design shall be properlydocumented and readily available. Cross-references torelevant data and clauses of codes shall be explicitlymentioned at every stage.

4.2 Design and construction of buildings, structures shall take intoaccount requirements of operation and maintenance of allequipment and its users. All the design work shall be carriedout as per latest IS codal requirements. The buildings shallhave good architectural features.

4.3 The tenderer is free to use STAAD Pro software for thepurpose of analysis. However detailed working of design shall


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be submitted based on the results of analysis. The tenderershall be solely responsible for the analysis results and thedesign not withstanding the approval accorded by theConsultant. If in the opinion of the consultant the results arenot satisfactory, alternate method of analysis and design shallbe used with the approval of Consultant.

4.4 Preliminary soil investigation of different site indicates thatordinary spread footing/raft will suffice for various structures.However, the tenderer shall carryout his own soil investigationand satisfy himself on the characteristics of soil and type offoundation system to be provided. No claim shall beentertained on account of ignorance of soil characteristics.

5.0 LOADS AND LOAD COMBINATIONS

5.1 General

5.1.1 All structures shall be designed for the most criticalcombinations of different loads. The loads shall include, dead

loads, imposed loads, equipment loads, crane loads, slurrypiping (static & dynamic) and other piping loads, wind loads,seismic loads, temperature loads, Blast loads, forcesdeveloped due to differential settlement and any other loadingconditions which can occur during the design life of the facility.All codes and standards referred are the latest editions/revisions along with amendments if any.

5.2 Dead loads

5.2.1 Dead loads consist of the weights of the complete structure

with finishes, fixtures, partitions, wall panels and allequipment of semi-permanent nature including tanks, bins,partitions, roofing, piping, cable trays, bus ducts etc. Thecontent of tanks, silo, bins and hoppers etc. shall be measuredat full capacity for this purpose.

5.2.2 The piping loads, cable tray loads and the contents of thetanks, bins and hoppers shall be listed separately so that theycan be excluded from dead load when dead loads are acting asstabilising load for uplift.


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5.2.3 The following unit weights of materials shall be considered forcomputing loads. Loads given in IS: 875 (part-I) shall bemade use of for the material not listed below.

Materials Unit weightPlain cement concrete : 2.40 t/cumReinforced cement concrete : 2.50 t/cumStructural steel : 7.85 t/cumCement plaster : 2.10 t/cumFloor Finish : 2.40t/cum

5.3 Imposed loads

5.3.1 Imposed loads in different areas shall include live loads, dustloads, minor equipment loads, cable trays, small pipe racks /hangers, erection loads, operation/ maintenance loads, etc.The loads considered shall not be less than that specified inIS:875 (Part II). The loads listed hereunder are the minimumloads for the areas involved. Special use areas shall beinvestigated and loads revised upward as necessary. Floors

and supporting members which may be subjected to heavyequipment live loads shall be designed on the basis of theweight of equipment or specifically defined live loads,whichever is greater.

5.3.2 The specific minimum floor live loads are listed belowRoofs:

A) Flat Roof : 1.50 kN / sqm for roofs

B) Main control room/ electrical buildings

a) Control room floor : 10 kN / sqmb) MCC room : 15 kN / sqmc) plant floors : 10 kN / sqmd) Switch gear room : 15 KN / sqm

C) Other areas

i) RCC floors : 5 KN/sqm for amenitiesBuilding and generalfloors

ii) Toilet : 2 KN / sqm


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5.3.3 Culverts and allied structures including RCC pipes shall bedesigned for Class AA loading and checked for Class Aloading as per IRC standards.

5.3.4 Covers for trenches & channels, which are not exposed tovehicular traffic, shall be designed for live load of adjoiningarea or 2 t / sqm whichever is higher. Where covers fortrenches and channels are likely to be exposed to vehiculartraffic, the requirements of code of practice for road bridgesshall be adhered to.

5.3.5 In addition to the live loads, a minimum of 0.50 kN / sqm shallbe considered as Hung loads for electrical, ventilation & airconditioning. Load of 1.0 kN / sqm shall be considered asHung loads for piping unless otherwise mentioned.

5.3.6 Live load reduction shall be in accordance with the provisionsof IS:875 and IS:1893 in case of seismic analysis.

5.4 Earth pressure loads

5.4.1 Earth pressure for all underground structures shall becalculated using coefficients of earth pressure at rest,coefficient of active or passive earth pressure (whichever isapplicable). However, for design of cold water basin of coolingtower and under ground liquid storage tanks earth pressure atrest shall be considered. Temperature stresses shall also beconsidered for tanks subjected to the same like hot waterstorage tank.

5.4.2 In addition to earth pressure and ground water pressure, etc.

a minimum surcharge load of 2.0 t/sqm shall also beconsidered for the design of all underground structuresincluding channels, sumps, cable and pipe trenches, etc. totake into account the vehicular traffic in the vicinity of thestructure.

5.5 Wind load

5.5.1 Wind load on structures shall be calculated as per provisions ofIS:875 (part 3). The wind shall be assumed to blow in anydirection and most unfavourable condition shall be considered

for design.


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5.5.2 In design of structures, wind force on equipment supported onframe including all fixtures, piping, staircases, ladders,handrails, etc. shall also be considered.

5.6 Seismic loads

5.6.1 Seismic analysis using response spectrum method as perIS:1893 shall be done.

5.7 Equipment loads

5.7.1 Static and dynamic loads of major equipment shall be basedon the manufacturers data of the specified equipment andshall be considered in design in addition to the live load.

5.7.2 The design for the supporting structure for vibrating screens,chutes, and hoppers shall be based on the load data (bothstatic and dynamic) supplied by the manufacturer. Thesupporting structure for all vibratory equipment shall beproperly isolated from building structures.

5.7.3 The design parameters like, natural frequency, operatingfrequency of the equipment, load combinations, slenderness ofcolumns, deflections of beams etc., shall be considered in thedesign as per the manufacturers recommendations.

5.7.4 In case of disagreement between codal and manufacturersstipulations on the limiting values of various designparameters, the tenderer shall follow the most stringentprovisions in the design.

5.7.5 The supporting structures for equipment shall be bracedadequately in both vertical and horizontal planes to achieverigidity.

5.7.6 Necessary platforms, staircases, walkways and sufficient roomaround equipment shall be provided for smooth maintenanceoperations. Necessary space around the vibrating screensshall be provided for inspection purpose.

5.7.7 All equipment, tanks and piping design loading shall includehydraulic test loading. Weight of equipment, ducts, tanks,

pipes, conduits, etc. supported by structure shall includemaximum possible loading conditions i.e. flooded conditions


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and associated impacts, test loading, anchorage and constrainteffects.

5.7.8 Blast loads

All structures shall be designed for resisting Blast loads as perIS:4991 and IS:6922.

5.8 Other loads

5.8.1 Stresses imparted to structures due to differential settlements,variation of water table, erection and maintenance loads,temperature variation, creep and shrinkage shall also beconsidered in design of all structures.

5.9 Basic load cases

5.9.1 The following basic load cases shall be considered for theanalysis as a minimum:

i) Dead load : Dii) Self weight of permanent equipment : ELiii) Live load on floor/walkway : Liv) Live load on roof : LRv) Crane load with lift : CR1vi) Crane load without lift : CR2vii) Wind load : WLviii) Seismic load : SLix) Load due to soil pressure : SPx) Load due to surcharge : SCLxi) Load due to hydrostatic pressure : HP

xii) Load due to temperature : TLxiii) Special loads : SPLxiv) Blast loads : BLxv) Erection loads : LE

5.10 Load combinations

5.10.1 The individual members of the frame shall be designed forworst combination of forces such as bending moment, axialforce, shear force and torsion. Permissible stresses fordifferent load combinations shall be taken as per IS:875 (Part-

V) and other relevant IS code. Wind and seismic forces shallnot be considered to act simultaneously.


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5.10.2 Criticality of erection / maintenance loads shall also bechecked separately in combination with other simultaneouslyoccurring loads for possible design loading.

5.10.3 Load combinations for underground structures

5.10.3.1 Following loading conditions shall be considered in addition tothe loading from super structure for the design of substructure of channels, sumps, tanks, trenches and other underground structures.

5.10.3.2 Only liquid pressure from inside and no earth pressure andground water pressure and surcharge pressure from outside(applicable only to the structures which are liable to be filledwith water or any other liquid).

5.10.3.3 Earth pressure, surcharge pressure and ground water pressurefrom outside and no water pressure from inside.

5.10.3.4 Design shall also be checked for buoyancy due to groundwater during construction and operation stage. Minimum factorof safety as per IS:3370 against buoyancy shall be ensuredconsidering empty condition ignoring superimposed loads.

6.0 REINFORCED CONCRETE STRUCTURES ANDFOUNDATIONS

6.1 General

6.1.1 All structures, building foundations, machines / equipment

foundation, water retaining structures, trenches, pits, etc.shall be designed as per latest relevant IS codes in general.Construction in general shall follow provisions of IS:456 2000 and IS:3370 for normal and liquid retaining structuresrespectively.

6.1.2 All designs of RCC structures shall be carried out by limit statemethod as per IS:456 2000 unless use of working stressmethod is specifically mentioned. Design strength of materialsand design loads shall be calculated using appropriate partialsafety factors over characteristic strength and characteristic

loads as per IS:456 - 2000


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6.1.3 For reinforcement detailing IS:5525, SP-34 and IS:13920 shallbe followed.

6.1.4 The walls shall be provided with reinforcement on both facesfor sections 150 mm or more, even if not required from designconsideration.

6.2 Foundations and Underground Structures

6.2.1 Type of foundation system, i.e. isolated, strip, or raft shall bedecided based on the loading arrangement, load intensity andsoil strata. Design of foundations at various levels shall bedependent upon the soil bearing capacity at that level.

6.2.2 Foundation system adopted shall ensure that settlement /relative settlement is as per provision of IS:1904 and otherIndian Standards. However, the settlement shall be restrictedto a lower value, if necessary as per the system requirement.

6.2.3 All foundations including machine / equipment foundations

shall be of RCC construction. All foundations shall be designedin accordance with relevant parts of the latest revisions ofIndian standards IS:2974 and IS:456. Raft foundations shallbe designed as per IS:2950.

6.3 Liquid Retaining Structures

6.3.1 RCC liquid retaining structures like storage tanks, over headwater tank etc. shall be leakproof and designed as uncrackedsection in accordance with IS:3370 (Part 1 to IV) by workingstress method.

6.3.2 All liquid retaining / storage structures shall be designedassuming liquid upto the height of wall irrespective ofprovision of any over flow arrangement. No pressure relievingdevices shall be permitted in underground structures.

6.3.3 In all liquid retaining structures, PVC water bar shall beprovided at each construction / expansion joint. The sequenceof construction shall also be specified on drawings showingconstruction joints.


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6.4 Machine Foundations

6.4.1 The design of machine / equipment foundation shall be as perIS:456 and IS:2974.

6.4.2 All machine / equipment foundations and structures subject tovibrations shall be suitably proportioned so that amplitude andfrequency of the foundation / structures are within permissiblelimits.

6.4.3 In all block foundations resting on soil, the mass of the RCCblock shall not be less than three times mass of the machine.Dynamic analysis shall be carried out to calculate naturalfrequencies in all modes including coupled modes and tocalculate vibration amplitudes. Frequency and amplitudecriteria as laid down by the relevant codes or machinemanufacturers shall be satisfied. Minimum reinforcement shallbe governed by IS:2974 and IS:456.

6.4.4 For the foundations supporting minor equipment weighing less

than one ton or if the mass of the rotating parts is less thanone hundredth of the mass of the foundation, no dynamicanalysis is necessary. However, if such minor equipment is tobe supported on building structures, floors, etc. suitablevibration isolation shall be provided by means of springs,neoprene pads, etc. and such vibration isolation system shallbe designed suitably.

6.4.5 Pumps, ID fans shall be supported on conventional framed /block type RCC foundations.

6.4.6 All such foundations shall be separated from adjoining parts ofbuilding and other foundations. Joints at floor / slab shall besuitably sealed. All appendages to such foundations shall bereinforced suitably to ensure integral action.

6.5 Increase in Stresses

6.5.1 Where stresses due to wind (or seismic) and temperature arecombined with those due to other loads, the allowable stressesin concrete and reinforcement steel shall be as per relevantIndian Standards in case of working stress design. However,

where the wind load is the predominant load on the structure,no increase in permissible stresses is allowed in case of


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working stress design.

6.5.2 Bearing capacity of the soil shall be allowed to increase by25% under wind load condition. Increase of bearing capacityunder seismic conditions shall be as per IS:1893.

6.6 Stability of Structures

6.6.1 Design shall be checked against buoyancy due to the groundwater during construction and maintenance stages forstructures like under ground storage tanks, pits, trenches, etc.Minimum factor of safety of 1.2 against buoyancy shall beensured considering empty condition inside and ignoring thesuperimposed loading. For purpose of calculating downwardload due to any overburden, only the mass located verticallyabove the projected area of the base slab shall be taken in toconsideration.

6.6.2 All building sub-structures including pump houses / retainingwall shall be checked for sliding and overturning stabilityduring both construction and operating conditions for various

combination of loads. Factor of safety for these cases shall betaken as mentioned in IS:456 and other latest relevant IScodes. However, following minimum factor of safety shall befollowed:

a) Factor of safety against overturning due to wind,seismic or other lateral load shall be 1.5 minimum

b) Factor of safety against sliding shall be 1.5 minimumc) Factor of safety against uplift due to hydrostatic forces

shall be 1.2 and due to any other loads shall be 1.5.

6.6.3 In cases where dead load provides the restoring force, only0.90 times characteristic dead load shall be considered.Imposed loads shall not be considered as restoring force.

6.7 Minimum. Thickness of concrete structural elements

6.7.1 The following minimum thicknesses shall be followed:

a) Suspended floor / slab/ walkways / canopy slabs etc:200 mmb) Ground floor slab (non-suspended) : 150 mmc) Water retaining slabs / walls, building walls : 200 mm

d) Cable/pipe trenches/underground pits/launder wallsAnd base slab : 125 mm


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e) All footings (including raft foundations) : 400 mmf) Parapets : 125 mmg) Sunshades at edge : 75 mmh) Precast lauvers / fins : 50 mmi) Precast trench cover slabs / floor slabs / louvers : 75 mm

6.7.2 From fire resistance point of view minimum thickness ofreinforced concrete members shall be as per of IS:456 -2000. Minimum fire rating of 2 hours shall be consideredwhere fire hazard is expected.

6.8 Minimum heights for pedestals of steel columns:

6.8.1 Top of RCC foundations (pedestals) shall normally be kept at alower level so that the column base plates together withgussets and stiffeners remain below finished floor level (FFL)unless specified otherwise. Encasing of pedestals for steelcolumns shall be done, wherever required, as per Clause No.6.9. Foundation levels for columns shall be decided toaccommodate underground services, pits, trenches, etc.

6.8.2 Stair and ladder pedestal shall be kept 200 mm above thefinished floor level.

6.8.3 Pedestals for steel columns for equipment structures:

a) Equipment in open area : as required (300mm min)

b) Equipment in covered area : as required (150mm min)

c) Structures and equipment : as per vendors data

supplied by vendor subject to minimum asspecified above.

6.9 Minimum heights for encasement of steel columns

6.9.1 In case the top of pedestal is kept at a lower level so that thecolumn base plate together with gussets and stiffeners remainbelow finished floor level (FFL) the column bases as well as thecolumn sections shall be encased in concrete, above FFL as perfollowing:

a) Open area : 300mm above paved levelb) Covered area : 150mm above FFL


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The size of encasement shall be equal to the size of RCCpedestal.

6.10 Concrete mix

6.10.1 Cement used shall conform to the following standards:-43 Grade Ordinary Portland Cement IS: 8112-1989

6.10.2 In case the chemical nature of the soil warrants special cementshall be used for structures below ground level

6.10.3 The proportions for nominal mix of concrete shall be as perTable 9 of IS:456. Nominal mix in concrete shall be allowed forgrades up to M 10 only and all other grades of concrete shallbe with Design Mix concrete in accordance to IS:456 andSP:23.

6.10.4 The concrete grade used for different structures shall be asfollows:

M5 Fill concrete

M7.5 Leveling course below foundations, trenches andunder ground structures.

M10 Foundation below concrete block wall, RR masonrywalls.

M15 Pavement around buildings including plinthprotection work, damp proof course below

concrete block work, Base plate encasement,encasement of structural steel work, block areapaving, screed concrete, etc.

M25 Reinforced concrete work for foundations, framedstructure, under ground structure, Equipmentfoundations, water retaining structure etc. as perdesign requirement.

6.10.5 Minimum cement content, maximum water cement ratio, andminimum grade of concrete shall be considered as per IS:456

for moderate exposure condition. Weigh batching plant shallbe mobilized for all types of RCC works.


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6.11 Reinforcement steel

6.11.1 Reinforcing bars for concrete shall be TMT bars with strengthrequirements conforming to IS :1786-2008 of Grade Fe 415

manufactured by preferred manufactures.

6.12 Grouting

6.12.1 Non-shrink flowable grout shall be used for under pinning workbelow base plate of columns. Non-shrink cum plasticiseradmixture shall be added in the grout. For grouting of base ofmachine foundation high strength ready mixed non-shrinkflowable grout shall be used.

6.12.2 Crushing strength of the grout shall generally be one gradehigher than the base concrete. Minimum grade of grout shallbe M 30.

6.12.3 Nominal thickness of grouting shall be at least 50mm for

building columns and pedestals of major equipment. Forsecondary posts, stair and ladder base,etc. grouting shall notbe less than 25mm thick.

6.13 Foundation bolts and insert plates

6.13.1 Minimum distance from the anchor bolt to edge of pedestalshall be the maximum of the following:

6.13.2 Clear distance from the edge of base plate / base frames to theouter edge of the pedestal shall be minimum 50mm.

6.13.3 Clear distance from the face of pocket to the outer edge ofpedestal shall be 75mm.

6.13.4 Clear distance from the edge of sleeve or anchor plate to theedge of pedestal shall be 75mm.

6.13.5 Steel templates shall be used for placement of bolts in positionin all types of foundations. Foundation bolts and pockets shallbe pre-fabricated before placing them in position.

6.13.6 Anchor bolts shall be designed for working stress, in tensionand shear and for required embedded length in concrete.


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Shear and crushing strength of concrete shall also be checked.Increase in allowable stress for loading including seismic andwind loads shall not be permitted in design of anchor bolts.

6.13.7 Insert plates shall be designed/checked for shear and bendingmoment. All lugs shall be checked for tension. Bond strengthof concrete shall also be checked. Lugs using steel bars shallpreferably be fillet welded to the plate to transfer full strengthof the lug.


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SECTION III: DETAIL SPECIFICATION FOR CIVILCONSTRUCTION WORKS

CONTENTS

Section Title

C-01 Technical Specification for site clearance and levelling

C-02 Technical Specification for Excavation and backfilling

C-03 Technical Specification for Anti - termite treatment

C-04 Technical Specification for Soling and Hardcore

C-05Technical Specification for Plain & reinforced concrete and alliedworks

C-06 Technical Specification for Masonry and Allied Works

C-07 Technical Specification for Plastering & pointing

C-08 Technical Specification for Flooring & Allied Works

C-09Technical Specification for Steel Doors, Windows, Ventilators,

LouversC-10 Technical Specification for wood work, carpentry & joinery

C-11 Technical Specification for Rolling Steel Shutter & Grills

C-12 Technical Specification for Aluminum works

C-13 Technical Specification for Glass and Glazing

C-14Technical Specification for Painting, White-Washing.Distempering and other finishing work

C-15Technical Specification for Drainage, Sanitation and Water

Supply

C-16 Technical Specification for Road & Pavements

C-17 Technical Specification for Supply and Laying of RCC pipes

C-18Technical Specification for Water proofing treatment for flat

roof.


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C - 01: SITE CLEARANCE & LEVELLING

1.0 SITE CLEARING

1.1 This specification covers the requirements of site clearance

and site leveling.

1.2 The Tenderer shall inspect the site to determine the extent of

all items to be cleared and the cost of this work is deemed tobe included in the item allowed for site clearance.

1.3 No trees or bushes are to be cut without the prior approval ofthe Department who shall have to be notified at least 48 hoursbefore starting this work. All trees and bushes cut shallbecome the property of the Department and shall have to be

stacked in an orderly manner by the Tenderer and as directedby the officers of the Department adjacent to the main road so

that they can be easily loaded on lorries by the Department

1.4 All boulders shall be stacked in neat piles on approved sitesand locations.

1.5 All combustible matter shall be disposed of as directed by the

Consultant

2.0 LEVELLING

2.1 The site shall be brought to a fairly good level for grid markingpillars to be established. The formation level of the site shall

be a minimum of 150mm higher than the average existingground level, unless otherwise specified in the drawings.

2.2 Any special natural features such as small hillock, trees, etc.,

shall not be disturbed and shall form part of light landscapedarea.

2.3 The site development includes leveling and filling, outside theboundary for approaches, construction of compound walls,drains, and culverts at required locations


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C- 02 : EXCAVATION WORK AND BACKFILLING

1.0 SCOPE

1.1 This section of the specification covers the technical

requirements for excavation & filling around structures,buildings, pipes, foundations, trenches, pits, drains, channels,cable ducts, underground facilities & similar works. It also

covers filling areas and plinths with selected materials,conveyance and disposal of surplus spoils at the waste dumpsshown on the drawings and/or stacking them properly as

directed by the Engineer/Consultant.

1.2 The Tenderer shall be fully responsible for proper setting out

works, profiling in excavation, stacking, etc. taking adequatesafety measures etc. The Tenderer shall carry out all works

meant within the intent of this specification even if notexplicitly mentioned herein. All works shall be executed to thesatisfaction of the Consultant.

1.3 Existing trees, shrubs, any other plants, pole lines, fences,signs, monuments, buildings, pipelines, drains, sewers or

other surface or subsurface systems/ drainage facilities withinor adjacent to the works being carried out which are not to bedisturbed, shall be protected from damage by the Tenderer.The Tenderer shall provide and install suitable safeguards

approved by the Consultant for this purpose.

1.4 Excavated material if permitted by Consultant shall be used forfilling/ backfilling. Unsuitable material/ excess material shall be

disposed off in layers not more than 150mm as directed byConsultant at waste dump locations to be indicated during

execution.

2.0 GENERAL

2.1 The Tenderer shall make his own surveying arrangements forlocating the coordinates and positions of all work and

establishing the reduced levels (RLs) at these locations basedon two reference grid lines and one bench mark which will befurnished by the Owner. The Tenderer has to provide at site all

the required survey instruments, along with qualifiedsurveyors, to the satisfaction of the Consultant so that the


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work can be carried out accurately and according to thespecification and drawings.

2.2 The Tenderer shall control the grade in the vicinity of allexcavations so that the surface of the ground will be properly

sloped or dyked to prevent surface water from running into theexcavated areas during construction.

2.3 Excavation shall include removal of trees including roots &

organic remains, vegetation, grass, bushes, shrubs, plants,poles, fences etc. that are in the area to be excavated as well

as beyond the excavation line so as to ensure safety of theexcavated side slopes and of men and equipment operating inthe area. Before start of excavation work, joint measurementsof ground level shall be taken after clearing all grass,

vegetation etc.

2.4 Excavation shall include the removal of all materials requiredto execute the work properly and shall be made with sufficientclearance as decided by the Consultant to permit the placingand setting of forms, inspection and completion of all works to

the satisfaction of the Consultant for which the excavation wasdone.

3.0 CODES AND STANDARDS

3.1 All standards, specifications, acts and code of practice referred

to herein shall be the latest editions including all applicableofficial amendments and revisions.

3.2 In case of conflict between this specification and those (IS

standards, codes etc.) referred to here-in, the former shallprevail.

3.3 Some of the relevant Indian standards, Acts and Codes arereferred to here below:

IS: 3764 1992 Safety code for excavation work

IS: 4081 1986 Safety code for blasting and related drillingoperations

IS: 4701 1982 Code of practice for earth work on canals

IS: 9759 1981 Guide lines of dewatering during

construction


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IS: 10379 1982 Code of practice for field control of moistureand compaction of soils for embankment andsub grade

Indian Explosives Act 1940 as updated.

4.0 EXCAVATION IN SOIL

4.1 Side and bottom of excavation shall be cut sharp and true to

line and level. Undercutting shall not be permitted. Whenmachines are used for excavation, the last 300 mm beforereaching the required level shall be excavated manually or by

such equipment that soil at the required final level will be leftin its natural condition. Suitability of strata (at the bottom ofexcavations) for laying the foundation thereon shall be

determined by the Consultant.

4.2 Excavation for foundation shall be to the bottom of lean

concrete and as shown on drawing or as directed by theConsultant. The bottom of all excavations shall be trimmed torequired levels and when excavation is carried below such

levels by error, it shall be brought back to the specified levelby filling with concrete of nominal mix (1:3:6) (cement: coarsesand: 40 mm down aggregates) as directed by the Consultantat no extra cost to the owner.

4.3 All excavation for installation of underground facilities, such as

pipe lines, drain lines etc. shall be open cuts. For deep andhuge excavations and in other excavations, if required by theConsultant, the Tenderer shall submit for Consultantsapproval an Excavation Scheme showing the methodology to

be adopted for excavation.

4.4 When excavation requires bracing, sheeting or shoring etc. theTenderer shall submit drawings to the Consultant, showingarrangements and details of proposed installation. TheTenderer shall also furnish all supporting calculations as called

for and shall not proceed until he has received writtenapproval from the Consultant. However, the responsibility for

adequacy of such bracing, sheeting, shorting etc. will rest withthe Tenderer, irrespective of any approval of the Consultant.

4.5 The Tenderer shall have to constantly pump out any water

collected in excavated pits and other areas due to rain water,springs etc. and maintain dry working conditions at all times


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until the excavation, placement of reinforcement, shuttering,concreting, backfilling is completed. The Tenderer shallremove all slush/muck from the excavated areas to keep the

work area dry. The Tenderer, if required, shall employ sludgepumps, for this purpose.

4.6 The Tenderer shall remove all materials arising fromexcavations from the vicinity of the work either for directfilling, stacking for the subsequent filling or for ultimate

disposal at the waste dumps shown on the drawings and asdirected by the Owner/Consultant. In no case shall the

excavated soil be stacked within a distance of 1.5 m from theedge of excavation or one-third the depth of excavationwhichever is more. Material to be used for filling shall be keptseparately.

5.0 EXCAVATION IN ROCK

5.1 For the work of excavation in rock, Tenderer shall engagespecialized agency having experience of excavation in rockinvolving wedging and blasting. The agency shall be approved

by Consultant and the Tenderer shall furnish details of relevantexperience in support while seeking approval for the agency.All relevant approvals from the Licensing agency and

regulations shall be followed.

5.2 In case of over breaks in rock excavation, the excavated level

shall be brought to the level shown on drawings with plaincement concrete of nominal mix (1:3:6) as described earlier.

5.3 Where blasting is prohibited for any reasons or it is not

practicable in the opinion of the Consultant, then theexcavation shall be carried out by chiseling, wedging or any

other approved method. The decision of the Consultant in thisregard shall be final binding on Tenderer.

6.0 EXCAVATION BELOW GROUND WATER TABLE

6.1 The Tenderer shall dewater and maintain dry workingconditions by maintaining the water table below the bottom of

the excavation level by well-point dewatering or deep welldewatering or any other method approved by the Consultant.

He shall continue doing so till excavation, concreting, curing,and all other operation included in the scope of work, which


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require dry condition in the area are completed.

7.0 FILLING

7.1 Materials

7.1.1 Materials to be used for filling purpose shall be approvedearth, stone, sand or other inorganic materials and they shallbe clean and free from shingle, salts, organic matter, large

roots and excessive amount of sod, lumps, concrete or anyother foreign substances which could harm or impair the

strength of the substances in any manner. All clods shall besuitably broken to small pieces. When the materials are mostlyrock boulders, these shall be broken into pieces not largerthen 150 mm size. Sand used for filling shall be clean, medium

grained and free from impurities. Fines less than 75 micronsshall not be more than 20%. In any case, the materials to be

used for filling purposes shall have the prior written approvalof the Consultant.

7.1.2 If excavated materials are to be used for filling, then the

Tenderer shall select the materials from the stockpile, land andtransport this material and execute the filling. This shallinclude excavation of earth, which may become hard due to

laying in stockyard for a long period of time.

7.1.3 In case the materials have to be brought from pits/quarries, it

shall be the Tenderers responsibility for identification of suchquarry areas, obtaining approval from their use fromconcerned authorities, excavation/quarrying loading and

carriage of such material, unloading and filling at specified

locations. The Tenderer shall pay any fees, royalties etc. thatmay have to be paid for utilization of borrow areas.

7.2 Filling Procedure

7.2.1 After completion of foundation, footings, walls and other

construction below the elevation of the final grades, and priorto filling, all temporary shoring, timber etc. shall besequentially removed and the excavation cleaned of all trash,

debris, and. perishable materials. Filling shall begin only withthe written approval of the Consultant. Also, areas identified

for filling shall be cleared of all soft pockets, vegetation,bushes, slash etc. In case of plinth and similar filling the


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ground shall be dressed and consolidated by ramming andlight rolling.

7.2.2 Fill materials shall not be dropped directly upon or against anystructure or facility where there is danger of displacement or

damage. Filling shall be started after the concrete/masonryhas fully set and shall be carried out in such a manner so asnot to cause any undue lateral thrust on any part of thestructure.

7.2.3 All space between foundation (concrete or masonry) and the

sides of excavation shall be filled to the original surface aftermaking allowance for settlement, Fill shall be placed inhorizontal layers not exceeding 200 mm loose thickness. Eachlayer shall be watered and compacted with proper moisture

content and with such equipment as may be required to obtaina compaction/ density as specified. Trucks or heavy equipment

for depositing or compacting fill shall not be used within 1.50meters of building walls, piers for operation. The methods ofcompaction shall be subjected to approval of Consultant underany circumstances.

7.2.4 Fill adjacent to pipes shall be free of stones, concrete etc. andshall be hand placed and compacted uniformly on both sides of

the pipes and where practicable up to a minimum depth of 300mm over the top of pipes. While tamping around the pipes,care should be taken to avoid unequal pressure.

7.2.5 Filling shall be accurately finished to line, slope, cross sectionand grade as shown on the drawings. Finished surface shall be

free of irregularities and depressions and shall be within

20mm, of the specified level.

7.2.6 Where filling with stone from excavated materials is specified,it shall be from broken pieces of boulders. At first a 75 mmthick cushion of selected earth shall be laid over which the200mm thick graded stones shall be laid in loose layers of

200mm, then the interstices filled with properly graded finematerials consisting of selected earth brought from borrowareas. Each layer shall be watered and compacted to the

specified density before the next layer is laid. However, nocushion shall be required where filling is over non-rocky

surface.


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7.2.7 Where filling with 65 mm down graded stone obtained fromexcavated, it shall be selected stone laid over and initial 50mm thick cushion layer of selected earth and then stone laid in

200 m loose thick layers, interstices filled with the specifieddensity before the next layer in laid. However, no cushion

shall, be required where filling isover non-rocky surface.

7.2.8 Where clean stone fill is specified, it shall consist of cleanselected stone metal of 40 mm nominal size. It shall be laid in

layers not exceeding 150 mm (loose) and lightly tampedbefore the next layer is laid. No compaction shall be required

for this type stone filling.

7.3 Compaction

7.3.1 Where compaction to 95% Standard Proctor Density or more iscalled for, it shall be by mechanical means only. Where access

is possible, compaction shall be by 12 tonne rollers smoothwheeled, sheep foot or wobbly wheeled as directed by theConsultant. A smaller weight roller may be permitted by theConsultant in special cases, but in any case not less than 10

passes of the roller will be accepted for each layer. Each layershall be wetted or dried by aeration to a moisture content of3-5% above the Optimum Moisture Content to be determined

by the Tenderer. Each layer shall be watered, rammed andcompacted to the density as specified Consultant.

7.3.2 For compacting each sand layer, water shall be sprayed andkept flooded for 24 hours to ensure maximum compaction.Vibro-compactors shall also be used if necessary to obtain the

required degree of compaction. Any temporary works required

to contain sand under flooded condition shall also beundertaken. The surface of the consolidated sand shall be

dressed to required levels or slope.

7.3.3 After the compacted fill has reached the desired level, thesurface shall be flooded with water for 24 hours, allowed to

dry and then rammed and consolidated to avoid anysettlement, at a later date. The compacted surface shall beproperly shaped, trimmed and consolidated to an even

gradient or level. All soft spots shall be excavated, filled andconsolidated.


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7.3.4 The degree of compaction of compacted fill in place will besubject to tests by the Consultant as the work progresses, andthe Tenderer shall provide the necessary facilities to make

such tests. If any test indicates that the compaction achievedis less than the specified degree of compaction, the Consultant

may require fill placed subsequent to the last successful test tobe removed and re-compacted by the Tenderer. Compactionprocedure shall be amended as necessary to obtainsatisfactory results.

7.3.5 When semi-compacted fill is specified by the Consultant, the

Tenderer shall fill up such areas with available earth fromstock piles of borrow pits or directly from excavation withoutspecial compaction except that obtained by moving trucks etc.


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C- 03 : ANTI - TERMITE TREATMENT

1.0 GENERAL

1.1 Pre-constructional antitermite treatment shall be provided toall buildings with a chemical barrier against the sub-terrain

termites.

1.2 Anti-termite treatment being a specialized job, should be got

executed through specialized agencies only. The specializedagency should be preferably a member of the Indian PestControl Association.

1.3 The scope of pre-constructional anti-termite treatment covers

the soil treatment with approved chemicals in water emulsionin foundation trenches for columns, plinth beams, pile caps,

brick walls, service trenches, lift pits, steps, ramps etc., in topsurfaces of plinth filling, at junction of walls and floor, inexpansion joints etc., in stages as detailed in thisspecifications and drawings, unless otherwise specified, the

anti-termite treatment will be carried out as per IS : 6313(Part-II)-2001 and or as per direction of the Consultant.

2.0 CHEMICAL TO BE USED

2.1 The following chemical in water emulsion, after approval fromthe Consultant, shall be used uniformly over the area to betreated.

CHLROPYROPHOS

2.2 The Tenderer should produce voucher (s) for the chemical

purchased and should get verified the sealed container(s) ofthe specified chemical from the Consultant before preparingthe emulsion / use for the treatment.

3.0 GUARANTEE

3.1 The Tenderer has to furnish the guarantee for 10 (ten) years

from the date of completion of work, stating that in case ofreappearance of termites within the building area due to

defective materials or workmanship or due to any otherreasons, the Tenderer will carry out the necessary post

constructional treatment to keep the entire area free from

termite, once again, without any extra cost to the Departmentduring the guarantee period.


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C 04 : SOLING & HARDCORE

1.0 GENERAL

1.1 The work covered under this specification includes all type ofsoling work either by rubble stones laid under floors / hardcoreunder foundations, hand packed, complete as per specification

and applicable drawings.

2.0 RUBBLE STONE SOLING

2.1 The rubble stone shall be of best variety of black trap / granite/ basalt or other approved variety of stone available locally.

The stone shall be hard, durable, free from defects and ofrequired size and shall be approved by the consultant beforeincorporation in the work.

2.2 Preparation of Surface & lying:

2.2.1 The bed on which rubble soling is to be laid shall be cleared ofall loose materials, leveled, watered and compacted and gotapproved by the Consultant before laying rubble soling. Cableor pipe trenches if shown in the drawing and as required by

the Consultant shall be got done before the soling is started.

2.2.2 Over the prepared surface, the stone shall be set as closely aspossible and well packed and firmly set. The stones shall be of

full height and shall be laid so as to have their bases of thelargest area resting on the sub-grade. Soling shall be laid in

one layer of 230mm or 150mm or other specified thicknessand no stones shall be less than 230mm or 150mm depth orspecified thickness of soling with a tolerance of 25mm.

2.2.3 After packing the stones properly in position, the intersticesbetween them shall be carefully filled with quarry spoils of

stone chips of larger size possible to obtain a hard, compactsurface. Spreading of loose spoils or stone chips is prohibited.

2.2.4 All interstices shall be filled with approved murrum. Excess

murrum if any over the surfaces shall be removed. Unlessotherwise specified, the murrum shall be supplied by the

Tenderer at his own cost from the selected areas. The surfaces

shall then be watered and consolidated with mechanical orsufficiently heavy wooden tampers and log-rammers as


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approved by the Consultant to give the required slope or leveland dense sub-base. After compaction, the surface shallpresent clean look. Adequate care shall be taken by the

Tenderer while laying and compacting the rubble soling to seethat concrete surfaces in contact with soling are not damaged.

3.0 HARDCORE