Quality Assurance Handbook for Rural Roads Volume-I - pmgsy

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Quality Assurance Handbook for Rural Roads
4. Construct box section in M25 concrete or as specified, with a maximum of one construction joint
located in the web below the fillet between deck slab and web.
5. Carryout concreting operation continuously upto the construction joint.
6. Ensure proper compaction of concrete using screed or form vibrator for concrete in top slab of
box. Use needle vibrators to ensure compaction of concrete in webs.
7. Provide pressure relief pipes of 100 mm dia. Mark an area of 500 mm x 500 mm below the pressure
relief pipe in the form of inverted filter as per clause 1302 of MoRD Specifications.
8. Provide cut off walls and protective apron as shown in drawing.
9. Provide earth cushion and/or pavement on the top slabs (carriageway) after specified period of
curing of all the box cells.
10. Provide 400 mm thick plain cement concrete parapet as per Clause 1208.4 of MoRD Specifications.
(c) Composite type (RCC deck slab on steel girders)
Choose Composite type bridges in hill areas or where problems of centering are foreseen for
casting of superstructure
1. Provide simply supported spans for composite type superstructure consisting of longitudinal
steel girders with RCC solid slab decking.
2. Provide shear connectors of appropriate size and spacing as shown in drawings between the Steel
girder and RCC deck to ensure composite action.
3. Ensure the composite section of steel beams and RCC slab and shear connectors conforming to
IRC:22 and IRC:24 and carry out welding works as per Table 1000.2.
4. Cast the RCC deck slab with steel reinforcements in place as per Sections 800, 900 and 1000.
5. Carryout painting and protective coating on Structural steel components in accordance with IS:1477,
with a minimum of three coats of paints or a metal coating followed by two coats of paint.
A4 Appurtenances
(a) Wearing Coat
Both bituminous and concrete pavements used in the adjacent road works, are carried over culverts
and minor bridges as wearing surface. However, separate bituminous or cement concrete wearing
coats are to be laid on RCC slab bridges, as shown in drawings.
1. Use 20 mm thick premix carpet with seal coat as bituminous wearing coat on culverts having
earth cushions and pavement carried over such culverts.
2. On minor bridges and culverts without earth cushion, provide 40 mm thick Bituminous Macadam
(BM) covered with 20 mm thick premix carpet and seal coat.
3. Where cement concrete pavement is being built for the road, carry the same over box culverts
with earth cushion or slab culverts.