REPAIR AND MAINTENANCE OF TARFELTING, ROOF TREATMENT AND ALLIED WORKS IN ALUMINA PLANT, NALCO, DAMANJODI

14.89.1) Providing and fixing APP (Atactic Polypropylene Polymer) modified prefabricated five layer 2 mm thick water proofing membrane , black finished reinforced with glass fibre matt consisting of a coat of bitumen primer for bitumen membrane @ 0.40 litre/sqm by the same membrance 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 350/300 N/ 5 cm.Tear strength in longitudinal and transverse direction as 60/80N.Softening point of membrane not less than 150°C. Cold flexibility shall be upto -2°C when tested in accordance with ASTM, D - 5147.The laying of membrane shall be got done through the authorised applicator of the manufacture of membrane

14.90.1) 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 @ 0.40 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. Cold flexibility shall be upto -2°C when tested in accordance with ASTM, D - 5147. The laying of membrane shall be got done through the authorised applicator only. APP 3 mm thick

22.14.1) Providing and laying grading concrete for water proofing treatment with cement concrete 1:2:4 (1cement: 2 coarse sand: 4 graded stone grit of 20mm and down nominal size) and water proofing compound as per manufactures specification and curing all complete as per direction of Engineer-in-Charge. (CEMENT SHALL BE ISSUED FREE OF COST AT NALCO'S STORE ).

12.41.2) Providing of fixing on wall face unplasticised-PVC moulded pipes with all fittings/ accessories for unplasticised rigid PVC rain water pipes conforming to IS:13592 Type A, including jointing with seal ring conforming to IS-5382, leaving 10 mm gap for thermal expansion. 110 mm dia meter

Repair of tarfelting defects like balooning, peeled off layers etc. by cutting out the damaged portion by knife or suitable means, application of blown bitumen and fusing of cut edges to bottom layer by heating with blow lamp, laying another layer of blown bitumen to receive new bitumen felt layer ( Hessian base or self finished bitumen felt), laying of blown bitumen for the final layer of stone grit of 6 mm etc. complete the new layer of bitumen felt should be provided with an over lap of 300 mm on all sides & at all heights.

14.1.2) Repairing to plaster of thickness 12mm to 20mm in patches of area 2.5sqm and under, including cutting the patch in proper shape, raking out joints and preparing, plastering the surface of the walls complete at all heights including disposal of rubbish to the dumping ground within 50 metres lead, curing etc all complete with cement mortar 1:4 (1 cement : 4 coarse sand) ( CEMENT SHALL BE ISSUED FREE OF COST AT NALCO"S STORE) (Necessary scaffolding shall be erected by the party at his own cost)

Dismantling of old tarfelting from roof at all heights & parapet wall and stacking the dismantled tarfelts within a lead of 100 M including all tools & tackles, labours etc. all complete as per the specification and direction of Engineer-in-Charge.

15.42.3) Dismantling of HCI rain water pipes of standard length at all heights including scaffolding ( if required), cleaning , refixing the same with proper alignment, cement jointing or returning to the Nalco store etc. complete as per direction of Engineer-In-Charge.

15.2.1) Dismantling and demolishing cement concrete work nominal mix 1:3:6 or richer mix including disposal of debris/ dismantled material lead of 50 mtrs. as per the direction of Engineer-in-Charge.

15.7.4) Demolishing brick / other masonry work manually/by mechanical means including stacking of serviceable material and disposal of un serviceable material within 50 mtr lead as per direction of EIC.(IN CEMENT MORTAR)