Quality Assurance Handbook for Rural Roads Volume-I - pmgsy

3. Section-1200
4. Provide 75 mm cement concrete wearing coat of M30 grade for isolated RCC slab bridges or
submersible structures where specified.
5. Keep a cross slope of 2.5 percent for deck slab level in longitudinal profile for drainage and ensure
curing earlier to prevent formation of shrinkage cracks.
(b) Bearings and Expansion Joints
1. Provide only elastomeric bearings for RCC slab bridges of span length more than 10m conforming
to IRC:83 part II.
2. Make provision for robust, durable, watertight and replaceable expansion joints, if needed. Such
joints shall be designed site specific or adopted as shown in drawings.
3. Install deck joints in accordance with manufacturer’s recommendation.
4. For the specifications of filler joints, buried joints, compression seal joints and slab seal expansion
joints refer to section 1200.7 of the MoRD Specifications for Rural Roads.
(c) Railings/Parapets
Bridge railings include portion of the structure erected on and above the kerb for the protection of
pedestrians and traffic and constructed after the centering for falsework released. Adopt either
metal or cast-in-situ concrete railings for RCC slab culverts and minor bridges as specified in the
drawings.
1. Adopt all pipe sections and steel elements of railings, conforming to IS:1239 after galvanizing.
2. Adjust railings carefully prior to fixing in place, to ensure proper matching at abutting joints and
correct alignment and camber throughout their length.
3. Protect all steel rail elements, pipe terminal sections, posts, nuts and both hardware and other
steel fittings against corrosion, by galvanizing or painting.
4. Construct portion of the railing or parapet to be cast in place in accordance with the requirements
for structural concrete as per Section 800 and reinforcement as per Section 1000.
5. For RCC slab culverts and minor bridges having overall length not exceeding 30 m, provide
parapets of 400 mm thickness (minimum) in PCC of M15 or brick or stone masonry as shown in
drawings.
6. Use forms of either single width board or line with suitable material duly approved.
7. Construct all mouldings, panel work and bevel strips as per drawings and finish all corners, true,
sharp and clean cut.
(d) Approach slabs
1. Approach slabs are not needed on culverts/or minor bridges having overall length not exceeding
30 m bridges and road pavement is continued in the full formation width between wing walls/
Returns.
2. When specified, adopt a minimum length of 3.5 m and minimum thickness of 300 mm for approach
slab. Provide a 150 mm thick base in M10 concrete for approach slab.
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