CONTRACT FOR PATCH REPAIRS OF BITUMEN MEMBRANE WORK AT UREA SILO 1 AND 2 IN PHP AT RCF THAL

Providing and erecting bamboo scaffolding arrangement over the parabolic shape silo including cleaning the ground area for movement of labours. Old/ cracked/ruptured bamboos shall not be used. Bamboo of dia. smaller than 35mm shall not be used. Spacing between two bamboos shall be 1.5m maximum. Ladder using bamboos shall be provided at suitable location for easy movement of workers.

Sealing of silo shell concrete cracks with SBR polymer modified cementitious grout/paste, including cleaning the crack, forming v groove etc.as directed.

Providing and laying APP (Atactic Polypropylene Polymer) modified prefabricated five layer 3 mm thick water proofing membrane, black finished reinforced with non-woven polyester matt consisting of a coat of bitumen primer for bitumen membrane @ 0.25 litre/sqm by the same membrane manufacture of density at 25°C, 0.87-0.89 kg/ litre and viscocity 70-160 cps. Over the primer coat the layer of membrane shall be laid using Butane Torch and sealing all joints etc, and preparing the surface complete. The vital physical and chemical parameters of the membrane shall be as under : Joint strength in longitudinal and transverse direction at 23°C as 650/ 450N/5cm. Tear strength in longitudinal and transverse direction as 300/250N. Softening point of membrane not less than 150°C. Note: 1)Prior approval of EIC must be taken before ordering membrane material. 2) Membrane material of fresh lot only shall be used. Material manufactured within four months from application date shall only be allowed to use. Older material will be rejected. 3) Material of 'Sika', 'STP' brands or their equivalent shall be used. Glass fibre based or mixed material based material will not be allowed to use.

Providing & applying 2 coats of aluminium paint of approved make, compatible to bitumen membrane as directed by EIC complete. Prior approval of EIC must be taken before ordering or using the paint. Manufacturer's Test Certificate shall be submitted. Material reconcileation will be done as per manufacturer's data (if not available, then material consumption per Sqm shall be established physically). If the material brought in, is lesser than required then,only proportionate area shall be paid.