Defence Research And Development Organisation Tender

Application of waterproofing layer: Prime the surface with Nitoproof WB primer. Primer & Providing two coats of liquid applied, solvent-free elastomeric waterproofing membrane, shall be made of hydrocarbon free polyurethane with at least 90% solid content- NITOPROOF 600PF. with necessary surface preparation, coving, primer etc. The waterproofing membrane shall be terminated on the top of parapet walls. The membrane when cured shall be capable of an extension of not less than 600%. Its tensile strength shall exceed 2.5N/mm2 and the water vapour transmissions shall be less than 1g/m2/24 hour. The Product Should have the Following Properties: Adhesion-in- peel test (N) (ASTM C836): 50N Recovery from 400% elongation (%) (ASTM D412-90): 95 Tear resistance (kN/m) (ASTM D624-00): 15 Water vapour transmission: 2.3mm film (g/m2/hr):0.6Initial hardness (Shore A) (ASTM 2240-86): 60 Water permeability (DIN 1048): 0 Chemical resistance: Unaffected by mild acids, alkalis and water borne salts. Does not biodegrade

Providing and fixing machine moulded aluminium covering of approved pattern & design, made out of machine cut aluminium sheet and machine holed for receiving dash fastener, over expansion joints on vertical surfaces/ceiling floors, the fixing on plate in one row on one side of joint only shall be done with stainless steel dash fasteners of 8 mm dia and 75 mm long bolt including providing aluminium washers 2 mm thick & 15 mm dia , at a staggered pitch of 200 mm centre to centre including drilling holes in the receiving surface and providing expandable plastic sleeves in holes etc. complete as per direction of Engineer-in-charge. Anodised aluminium sheet 2.5 mm thick (anodised transparent or dyed to required shade according to IS: 1868, Minimum anodic coating of grade AC 15)

Removal of Existing Brick bat coba / APP membrane layer Removal of Existing Brick bat coba / APP membrane layer over the roof using mechanical / manual means approved by the EIC and disposal of debris to the allocated location with in 50 meter from site. Item rate is inclusive of materials all labour, tools and tackles, and transportation etc. complete as per specification and as directed by Engineer-in-Charge.

Treating the Construction Joints & cracks: All charges for chase opening the Construction joints in groove size of 25 mm x 25mm and injecting cement slurry admixed expanding grout admixture Cebex 100 @225 gm per bag of cement within the prefixed nozzles under pressure using grout pump to fill all possible pores. (pressure of 2 to 2.5 kg/sqcm) Grooves should be filled with cement – sand mortar mixed with Nitobond SBR Latex @ 10 % by weight of cement.

System Application: Application of Nitobond PC40 both side edge & placing 1 mm thick & 200 mm wide Expoband one tape over the expansion joint. Placing 2 nd Layer of Nitobond PC40 to completely fix the Expoband one tape over the Concrete surface. Then apply 300 mm wide aluminium strip of 1mm thick to be provided on treated expansion joint to protect the surface/membrane by mechanical means. Item rate is inclusive of materials all labour, tools and tackles, and transportation etc. complete as per specification and as directed by Eng.-in-Charge.

Filling the gap in between aluminium frame & adjacent RCC/ Brick/ Stone work by providing weather silicon sealant over backer rod of approved quality as per site conditions and direction of Engineer-in-charge all complete. Upto 5 mm depth and 5 mm width

Coving at all the junctions to be done for a size of 50mm X 50mm with polymer modified mortar prepared by mixing 50 kg cement + 150kg Sand + 4Litre of Nitobond SBR Latex + Water required for mortar consistency

Surface Preparation: Clean all concrete surfaces free of laitance, dust, dirt, cavities, projecting nibs etc.by grinder and wire brush. Grease should be cleaned using a chemical degreaser and washed with clean water and allowed to dry. Remove all protrusions from concrete surfaces using a fine hair broom finish. Remove moss and lichen manually and treat the surface with a fungicide. Wash the surface thoroughly with clean water and allow it to dry. Standing water must be removed to prevent subsequent compromise of waterproof properties. Surface should be absolutely dry before application of Nitoproof 600PF. The surface should be grinded to remove contaminants, laitance and weak concrete, so as to have a sound concrete surface with adequate profile.

Horizontal protection (Screed): Providing and applying protective Screed of avg 50 mm thickness on treated waterproof area, in 2m x 2m panel. The concrete shall be admixed with Conplast WL Xtra @ 200 ml per bag of cement, compaction, finishing surface suitably, curing, cleaning, testing etc. Seal the 2m x 2m panel using Nitoseal PU 50. Complete all as per manufacturer's recommendations as directed by the Engineer.

Surface Preparation: Clean the surface free of dust, laitance, foreign particles, curing compounds etc. Prepare the surface to a width of 50 mm greater than that of the membrane. The prepared surface shall be free from irregularities, with pencil rounded arises and no vertical misalignment across the joint. Remove all traces of dampness from the surface using a gas torch or hot air blower. The substrate shall be considered dry enough when dampness does not re-appear within 15 minutes. Where Expoband One is going to be turned up parapets or other vertical surfaces, create a minimum 10 mm splay using Mortar. Expansion joints must firmly packed with a firm consolidated filler board and a joint sealant. Item rate is inclusive of materials all labour, tools and tackles, and transportation etc. complete as per specification and as directed by Eng.-in-Charge.