KAMRUP METRO/MMPNA/R_R/02 Repair AND Rehabilitation of bridge located at Azara Rani Loharghat (Rani NEC Road (Rani Chowk-Loharghat) at ch. 17.749 Km under Mukhya Mantrir Path Nabikaran Aachani for the year 2023-24

Amount

Chipping of deteriorated concrete and removal of all loose & friable materials and fully exposing rusted reinforcement followed by proper cleaning and removing of rusts and other foreign materials using sand blasting/ emery cloths/ wire brush etc. including formwork as directed and specified by the department complete

Supplying and applying Epoxy based bonding agent Nitobond EP of Fosroc Chemicals or MasterBrace 1414 of BASF or euivalent @ 0.50 Lit pe sqm after totally saturating the cleaned concrete surface with clean water for proper bonding of old and new concrete including formwork as specified and directed by the department complete.

Patching of damaged concrete surface with structural grade polymer modified reinstatement mortar to like Fosroc Renderoc S2 or equivalent at a thickness of 10 to 20mm as per instructions of manufacturer and as approved by the Engineer.The prepacked repair mortar should have a compressive strength 45 N/mm²,Flexture strength 8 N/mm² at 28 Days.

Concreting of the structure with free flow nonshrink cementitious microconcrete with Renderoc RG of Fosroc or equivalent after proper mixing with cleanwater including formwork followed by proper curing for 28 days as per manufacturer's specifications complete and as directed by the Department .

Repair of joint Grooves with Epoxy Mortar Repair of spalled joint grooves of contraction joints, longitudinal joints and expansion joints in concrete pavements using epoxy mortar or epoxy concrete)

Providing & fixing 16mm dia MS nozzles in a grid of 1m c/c up to the half of the thickness of the concrete structure.A grout slurry of neat cement & chloride free expanding grout Cebex 100 of Fosroc Chemicals or Mastergrout CPG-1 of Choksey Chemicals or MasterFlow 150 of BASF or equivalent @ 0.5% by weight of cement water cement ratio 0.35 to 0.40 and viscosity not more than 1.02 centipoise with grouting pressure till the refusal of injection grout . The grouting operation pressure shall be 2Kg/sq.cm.Cutting the exposed nozzle after the grouting with a good cutter to make the surface free from the grouting pipes and to seal the gap with plugging compound Masterplug of Choksey Chemicals as per the specification and the direction of the department complete including formwork.

Providing and inserting nipples with approved fixing compound after drilling holes for grouting as per Technical Specifications including subsequent cutting/removal and sealing of the hole as necessary of nipples after completion of grouting with Cement/Epoxy

Sealing of crack / porous concrete with Epoxy Grout by injection through nipples complete as per clause 2803.1.

Providing and applying Deckguard E 2000 or Masterseal 878 of BASf or equivalent a High Performance Anticarbonation Protective Coating System, over the prime surface using an airless spray or roller at right angles to each other @ coverage of 5 Sqm per litre per coat @ 200 microns wft / 100 microns DFT with an intercoat period of minimum 12 hrs @ 35ºC. The coverage per litre for 2 coats shall be 2.5 Sqm @ 200 microns DFT. The protective coating system should have CO2 diffusion resistance not less than 240mm equivalent of air thickness and 60cm equivalent of 30N concrete along with a water vapour transmission resistance of less than 1.0 metre (Taywood method), the coating should have static crack accommodation of not less than 2mm (BRE) and adhesion greater than 1.0 N/mm² as per BS 1881.

Replacement of Expansion Joints complete as per drawings

Strip Seal Expansion Joint (Providing and laying of a strip seal expansion joint catering to maximum horizontal movement upto 70 mm, complete as per approved drawings and standard specifications to be installed by the manufacturer/supplier or their authorised representative ensuring compliance to the manufacturer's instruction for installation).

Painting on concrete surface (Providing and applying 2 coats of water based cement paint to unplastered concrete surface after cleaning the surface of dirt, dust, oil, grease, efflorescence and applying paint @ of 1 litre for 2 Sq.m. ) For RCC Railing

Non-destuctive testing with Ultrasonic Pulse Velocity Meter with data storage facility for detection of cracks, voids and other imperfections in Reinforced concrete structures and furnishing the findings thereof in proper comprehensible format , complete as directed by the department.

Conducting Concrete Core tests of 75mm diacores, on concrete stucture, as per stipulated procedures, for determination the equivalent cube compressive strength, concrete of the structures including preparation and furnishing the report showing the findings thereof in proper comprehensible format , complete as directed by the department.

Competent Infrastructure and consulting(CICON) Pvt.Ltd

SRI HIRANYA PATHAK