Quality Assurance Handbook for Rural Roads Volume-I - pmgsy

C. Do’s and Don’ts
Do’s Don’ts
1. Locate Causeways and Submersible bridges far away
from the confluence of streams.
2. Adapt submersible bridges which blend aesthetically
in the environment.
3. Adopt guide post/stone of 250 mm dia of specified
height embedded full depth in concrete pavement
and in approach portion of causeway. Paint them
with alternative black and white bands with ordinary
paint.
4. Permit traffic on causeways and submersible bridges
after sealing of construction joints and 28 days curing
period of concrete.
5 Protect the stream bed on upstream and downstream
of causeway by providing aprons and other
protective works.
6. Anchor the superstructure of submersible bridges
with piers and abutments by using stainless steel
anchor rods.
7. At submersible bridges / causeways, follow the same
profile as the flanking road section without any break
in grade line. Provide properly designed vertical
curves to avoid jerks.
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Quality Assurance Handbook for Rural Roads
1. Do not choose submersible bridge if the mean velocity
of stream is high (exceeding 6m/sec).
2. Do not use composite type superstructure of steel
girder with CC solid slab decking for submersible
bridges.
3. Do not use fixed type railings for submersible bridges.
4. Do not adopt masonry substructure if the depth of
foundation is more than 7 m.
5. Do not use dry rubble masonry in retaining walls/
breast walls and if necessary in approaches of
submersible bridges.
6. Do not use metallic bearings for submersible bridges.
7. Do not provide gradients steeper than 1 in 20 on both
ends of causeways.