SPECIAL REPAIR TO BLDG NO P 942 STRENGTHENING OF EXTERNAL ELECTRICAL SUPPLY AND CONNECTED WORKS AND PROVN OF CERTAIN MAJOR REVENUE AND MINOR WORKS AT 16 TS CTI ETI AND E ITI

Chipping , removing carefullly concrete work by low impact hammer, breakar without damaging the structure & cleaning and disposal of debries out side the premises etc. complete all as directed. (Hard concrete should not be removed by force).

M & L for Carrying out application of ‘Bi-polar migratory corrosion inhibitor' on concrete surface. This inhibitor has migratory kind of property which permits the material to migrate to a virtual extent of 100 mm, through pores of concrete, inhibiting the corrosion and de-passivating the Electro-chemical reaction. It has property to attack anode as well as cathode, which is purely alkaline in nature (pH-9.5), so it has no carcinogen activity with concrete.

M&L for Drilling and fixing Rohibb Teflon nozzles in RCC members, including drilling holes of 12mm dia, 50 to 100mm deep holes. Works shall be carried out as under :- (i) Cleaning of holes. Clean the holes by air blower prior to fixing nozzles. (ii) Fixing of nozzles. Insert 12mm dia. Rohibb Teflon nozzles in cleaned holes. External end of nozzles to be machine to receive outlet of grouting gun. Fix it inside the holes by applying thixotropic epoxy putty to ensure complete sealing. Cure the system for min.12 hrs. (iii) Cutting of nozzles. Cut the nozzles by chisel after completion of grouting without damaging structural elements. (iv) In case crack upto 2mm wide, fix the injection nozzels directly over the cracks, at intervals of 6 to 9 inches, using a drilling machine. Fix PVC/MS nozzels in these holes with fast-setting epoxy putty & let it dry for 2 to 3 days. Also, seal the crack between the ports with epoxy putty. (v) In case where the crack is wider than 2mm upto 4 to 5mm, drill holes at the sides of the crack in a staggered fashion, at intervals of 6 inches and affix them with epoxy putty as mentioned above. (vi) Also, seal the face of the crack with a liberal application of the epoxy putty.

S& F chicken wire mesh fixed to RCC brick work joint all as specified and directed by Engr In Charge

M&L for Injecting of site mixed cement slurry grout, mixed in specified proportion containing cement, sand water with addition of plasticizers (approved make) & migratory corrosion inhibitors, water cement ratio shall be varied between 0.5 to 1.0 for each hole, shrinkage compensating cement slurry mixed to a lump free fresh creamy consistency , Mixing shall be done by mechanical mixer continuously stirring mechanically to keep cement particles in suspension. Injection of approved/specified grout by means of pump at a pressure of 3-5 Kg/cm2 etc complete till the grout mix flows out from the nozzle indicating complete filling of grout in the holes drilled.

M&L Injecting low viscosity (3-5cps) high molecular weight monomer by pressure and using mechanized injector gun with accessories till nozzles refuses to accept the grout, Including, Mixing of materialas: Mixing of material components(part a&b) in the required quantities as per manufacturer's instruction by weigh batching. Grouting:Fill the grouting gun with concrete penetrating corrosion inhibitor. Maintain desired pressure in the gun by air compressor; maintain the pressureat exit (2 to 3kg/cm2) by monitoring pressure guage at exit. Grout the material through prefixed nozzles in the structural elements@ 100ml per nozzle. Repeat the process for all the nozzles.

M & L for anticorrosive Treatment to Reinforcement by application of two coats of IPNET RB (CBRI Know how) by brush on exposed reinforcement with time interval of minimum 4 hours between each coat all as specified and directed.

M&L Providing and applying structural grade epoxy-latex bond coat prior to application of any type of mortar confirming to ASTM-C- 882-91 (Arizona Slant Shear Test) to ensure bond between old concrete & new concrete by brush application all as specified and directed.

Providing and applying jacketing around columns with Micro concrete (Molith-MC) M40 including all lifts, shuttering, drilling holes and fixing shear anchor as per specification complete.Note: Reinforcement shall be measured and paid separately.(Rates including jacketing, formwork and micro concrete) all as per manufacturer's instruction and as directed by the Engineer-in-Charge.