In River training work for bridge up to a height of about 12 m, the embankment is constructed _______
- AParallel to the river banksCorrect
- BTransverse to the river banks
- CInclined to the river banks
- DNone of the above
Solution
Concept
River training embankment orientation for bridges
Formula
NONE
Step-by-step solution
1. River training works protect bridge approaches and embankments from river erosion and flooding. 2. For embankments up to a height of about 12 m, marginal bunds or dykes are constructed along the river course. 3. These embankments are aligned parallel to the river banks to guide the flow smoothly through the bridge opening. Answer: A
Explanation
River training embankments or guide banks for moderate height structures up to 12 m are constructed parallel to the river banks. This parallel alignment guides the water flow smoothly towards the bridge opening without causing turbulence. It protects the surrounding lands and bridge approaches from scour and erosion.
Why the other options are wrong
B) Transverse embankments obstruct the river flow rather than training it parallel along the banks. C) Inclined embankments are used for spur or groyne designs rather than continuous river bank embankments. D) Option A is correct because the embankment is constructed parallel to the river banks.
Shortcut
Marginal bunds are constructed parallel to river banks.
Common mistake
Confusing river training embankments with groynes or spurs, which are constructed transverse or inclined to river banks.
Correct answer: A) Parallel to the river banks