Strengthening and Special repair of R.C.C. structure of Cooling Tower Stage I and II at RGTPP, Ramgarh

Scaffolding : Providing and fixing double scaffolding system (Cup lock type)on the exterior side of up to seven storied height made with 40mm diameter M.S. tubes 1.5m centre to centre horizontal and vertical tubes joining with cup and lock system with M.S. tubes, M.S. tubes challies, M.S. clamps and M.S. Staircase system in the scaffolding for working platform etc and maintaining it in a serviceable condition for the required duration as approved and removing it thereafter. The scaffolding system shall be stiffened with bracings, runners, connection with the building etc wherever require for completion of work at required locations with essential safety features for the workmen etc complete as per the directions and approval of Engineer- In-charge. The elevational area of the scaffolding shall be measured for payment purpose. Item No. 24.2, Page No. 1951-1952 (DAR 2023- Vol. 2)

Scaffolding Net : Providing and fixing Scaffolding net of required width made of high Density Polyethylene UV stabilized knitted on warp knitting machines having density 100gm/sqm and shading coefficient minimum 75% around the construction site/ for vertical extension as per requirement including fastening/tying with building/ scaffolding pipes or with any other fixtures etc. complete as per direction of Engineer-in-Charge. (One time payment shall be made for providing Scaffolding net from start of work till completion of work including shifting if any. The Scaffolding net shall be the property of the contractor on completion of the work) Item No. 26.81, Page No. 2086 (DAR 2023- Vol. 2)

Removal of disintegrated/cracked/loose makeup concrete or plaster. Chipping of unsound/weak concrete material from slabs, beams, columns etc. with manual Chisel and/ or by standard power driven percussion type or of approved make including tapering of all edges, making square shoulders of cavities including cleaning the exposed concrete surface and reinforcement with wire brushes etc. and disposal of debris for all lead and lifts all complete as per direction of Engineer-In-Charge 25 mm average thickness Item No. 26.28.3, Page No. 2011 (DAR 2023-Vol. 2)

NRV injection Nozzle Fixing : Providing and inserting 12mm dia.NRV Nozzle fixing in honey comb area and along crack line including drilling of holes of required diameter (20mm to 30mm) up to depth from 30mm to 80mm at required spacing and making the hole & crack dust free by blowing compressed air, sealing the distance between injection nozzles with adhesive chemical of approved make and allow it to cure complete as per direction of Engineer-In-Charge. Item No. 26.39, Page No. 2024-2025 (DAR 2023- Vol. 2)

Injection Epoxy grouting : Providing and injecting approved grout in proportion recommended by the manufacturer into cracks/honey-comb area of concrete/masonry by suitable gun/ pump at required pressure including cutting of nipples after curing etc. complete as per directions of Engineer-in-Charge. (The payment shall be made on the basis of actual weight of approved grout injected) Epoxy injection grout in concrete/RCC work of approved make Special Product: Master Inject 1315 (Master Builder) or Equivalent Item No: 26.35.3, Page No: 2020-2021, ( DAR - 2023 Vol. 2)

Shotcrete – 50mm thick for Dome shell Providing and casting ready to use cement based spray applied repair mortar for CT Fan Dome shell on external side using shotcrete machine at a pressure of 3 Kg/cm2 of approved brand and manufacturer. The maximum aggregate size shall be 5mm. The shotcrete application procedure shall be as specified by the manufacturer specification etc. complete as per the direction of Engineer-in-charge. Special Product: Master EmacoS810(BASF) or equivalent make. Item No. 26.38.2, Page No. 2023, (DAR 2023), Vol. 2

Chemically Modified Polymer Mortar Providing, mixing and applying SBR polymer (of approved make) modified Cement mortar in proportion of 1:4 (1 cement: 4 graded coarse sand with polymer minimum 2% by wt. of cement used) as per specifications and directions of Engineer-in- charge. Note: Measurement and payment: The pre- measurement of thickness shall be done just after the surface preparation is completed and Payment under this item shall be made only after proper wet curing has been done and surface has been satisfactorily evaluated by sounding / tapping with a blunt metal instrument and/or the 75mm size cube crushing strength at the end of 28 days to be not less than 30 N/Sqmm2). Special Product : Master Emaco SBR 2(Master Builder) or equivalent 12 mm average thickness. Item No. 26.32.1, Page No 2014-2015 (DAR 2023 Vol. 2)

Epoxy Bond Coat: Providing, mixing and applying bonding coat of approved adhesive on chipped portion of RCC as per specifications and direction of Engineer-In-charge complete in all respect. Epoxy bonding adhesive having coverage 2.20 sqm/kg of approved make. Special Product : Masterbrace 1414(Master Builder) or Equivalent Item No. 26.31.2, Page No. 2014 (DAR 2023- Vol. 2)

Welded Wire mesh: Providing and fixing hard drawn steel wire fabric of size 75 x25 mm mesh or other suitable size wire mesh to be fixed & firmly anchored to the concrete surface by means of "L" shaped mild steel shear key welded with existing reinforcement including the cost of materials, labour, tool & plants as approved by Engineer-in-charge. Item No. 26.40, Page No. 2025,(DAR 2023), Vol. 2

Steel reinforcement for R.C.C. work including straightening, cutting, bending, placing in position and binding all complete above plinth level. Item No. 5.22A.3, DAR Vol. I (2023), Page No. 277