Question

The existing width of the stream is contracted at the bridge site by _________

(a) U/s wing walls

(b) D/s wing walls

(c) Canal wings

(d) Drain wings

This question was posed to me in an online interview.

My question is taken from Culverts Construction topic in chapter Culverts and Small Road Bridges Construction of Irrigation Engineering

Answer 1

Right option is (a) U/s wing walls

The best explanation: It is done by U/s wing walls or training works so as to make it equal to regime width and the bridge may then be spanned across it. This contraction of the stream up to regime width leads to the economy since the bridge length is reduced.