REPLACEMENT OF HANGAR DOORS AND ALLLIED WORKS AT AF STATION BORJHAR

Hanger Door :- (a) Labour and machineries/ scaffolding for taking down the existing Hangar doors (Size 9.30 mtr X 9.20 mtr, 04 Nos leaf, bi-parting means 2 leaf each side, sliding leafs, in 1 hanger front and rear 4X2=8 leafs) with bottom track, bottom sleeper, top guide (but not any structure of hangar and without damaging the existing adjacent structures) from its original position wih proper safety measures complete all as specified and as directed. (b) M&L for designing new door leaf with light door made of hollow section, other steel structure bottom rail as rail guide and sleeper, top guide, fixing of top and bottom roller wheel assembly to the door leaf shaft with 03 nos wheel per leaf fixed at top and bottom, total 24 nos of wheels per entry, complete all as specified and as directed with following specifications: (i) The existing foundation of hangar doors track rails, sleeper shall be removed and the same duly shall be laid by cutting the existing PQC available at site by using diamond cutter machine without damaging existing adjacent pavement. The necessary repair/ reconstruction of floor of hangar after casting of foundation shall be done with pavement quality cement concrete of minimum flexural strength of 45 kg per sqcm in field using 400 kg of cement per cubic meter (design mix) laid with mechanical paver (min depth as per existing section) all as specified in design consolidated in bays to required gradient and camber including necessary stell form work and provision of suitable track rails as per design, complete all as specified and directed and approved by enginner-in-charge.

(Srl Item No 1.00 Contd....) (ii) Foundation of the Hanger Door shall be designed by for safe bearing capacity (SBC) values 12 tonne/ sqm or the actual safe bearing capacity values found on the ground. SBC test as required for design of structure shall be done by Govt approved agency. After SBC test from Govt approved agency design of foundation shall be vetted from any IIT and approved by CWE. Cost for SBC test and design vetting of foundation shall be included in quoted rates. (iii) The foundation of the concrete shall be of design mix M-30 as approved design duly vetted from IIT/NIT. The reinforcement steel shall be of grade Fe-500/Fe-550D as per approved design. (iv) Each door leaf shall be supported at the bottom on three load wheels. The wheels are made of Outer Dia 300 mm with 2Z ball bearing. (v) Each door is guided at top with three set heavy duty steel rollers. The wheels/rollers are made of OD 125 with 2Z self lubricated maintenance free ball bearing. All wheels are welded or bolted to the door frame, complete all as specified in approved design. (vi) All structure steel members of frame and supporting structure shall be grade Fe-410 W and yield strength of 250mpa (vii) All the items i.e. Structural steel , bolt , base plate, welding connections, sliding track, erections etc are included in the quoted rate for this item. Cost are inclusive of necessary scaffolding and formwork required to execute the work. (viii) The design and drawing of MS top and bottom frame work including anti fallen arrangement as cleat at top guide shall be vetted from any IIT before fixing/ fabrication duly approved by CWE. (ix) Auto track cleaner made of hard wire shall be fixed at bottom of each door leaf. This will automatically claen the track.

(Srl Item No 1.00 Contd....) (x) All safety arrangement shall be provided for safe operation of the hangar door as per guidelines/ international parameters of hangar door. (xii) Proper drainage system shall be provided near around bottom track to avoid any other water logging near bottom track and applied two coats of PU paint on all mild steel sections over a coat of primer (Spray painting by mechanical means). (xii) Anti fallen arrangement as cleat at top guide shall be provided. This will protect door from falling in case of failure of top roller wheel. (xiii) Any minor varriation in size should be consider as per site condition after duly approved by accepting officer

PU FLOORING Surface Preparation: Preparing the existing surface of floor by shot blasting/scarification and cleaning by wire brushing etc. to remove all dirt, dust, oil etc. to expose clean sound base concrete. Cost shall include treatment of construction and control joints filling as per manufacturer's specification and direction of Engineer-In-Charge. Any imperfections in the concrete shall be treated with suitable epoxy/polyurethane system as per manufacturer specification. Providing the anchorage grooves as per the proposed system thickness. Width should be equal to the thickness and depth should be twice of the thickness. Anchor grooves spread area should be every 2Sqm/floor panel size depending on speed of application. Crack treatment: Providing and applying Renderoc S2 (a heavy duty polymer modified cement mortar) or equivalent for cracks treatment, all the cracks shall be chased open to a 10mmx10mm groove and filled using Renderoc S2 or equivalent after necessary surface preparation. Expansion Joint Treatment: Providing and applying Cold applied, high performance, pitch free, Polyurethane pavement joint sealant “Colpor 200 PF” or equivalent after priming the surface. Coving: Providing and laying 50mmX50mm thick epoxy coving with Nitoflor coving UT or equivalent . Providing the anchorage grooves as per the proposed system thickness. Width should be equal to the thickness and depth should be twice of the thickness. Anchor grooves spread area should be every 2Sqm/floor panel size depending on speed of application.

(Srl Item No 4.00 Contd....) Polyurethane Concrete Topping–Dry Areas- Providing and applying a four component cementitious polyurethane floor topping at a thickness of 4 mm of approved manufacturer. A forced action rotary paddle mixer is recommended for mixing the product. Topping applied at 2/3mm thickness over a scratch coat of 1mm at 2Kg/Sqm or as per manufacturer's instruction to the designated area. The topping shall be applied at 3mm thickness at a coverage of 5.8Kg/Sqm or as per manufacturer's instruction and shall have a smooth matt finish. The Polyurethane Cementitious system shall exhibit the following properties: Compressive Strength (ASTMC106):28 days at 56MPa Tensile Strength (BS6316-7): 6.5 MPa Flexural Strength (BS6316-3):17.6 MPa Slip Resistance (ASTME303): Dry S56, Wet S66, 22/32 (Moderate Slip Risk) Impact Resistance (ASTMD2764): 3 mm thickness: 8.1Joules 6 mm thickness:11.1Joules High resistance to damage. Ensure that the construction joints, control joints and other anchorage grooves of 8mm× 8mm are fully wetted out with material at the edges, day joints, up stands, drains, doorways and at regular points across the floor and all debris removed. Note :- (i) All PU flooring work shall be completed in the presence of authorised manufacturer's representative. (ii) Contractor obtain the completion certificate from authorise manufacturer and submit the same to GE.