The selection of site for road bridges depends on :
- ANature of river banks and appropriate arches
- BWidth and depth of river at site to be bridged
- CAvailability of good and safe foundation for bridge
- DAll of the aboveCorrect
Solution
Concept
Factors for selecting road bridge site
Formula
NONE
Step-by-step solution
1. A narrow, well-defined river channel with stable banks reduces the overall span length and structural cost. 2. Depth and flow characteristics determine pier height, scour depth, and hydraulic design of the bridge. 3. Secure subsoil conditions ensure safe load transfer through foundations, making all these factors critical for site selection. Answer: D
Explanation
Selecting a bridge site requires a comprehensive evaluation of hydraulic, geotechnical, and structural conditions. Important parameters include bank stability, channel cross-section dimensions, and the presence of suitable foundation strata. Because all these factors directly affect bridge safety and economy, option D is correct.
Why the other options are wrong
A) River bank stability is only one consideration among several for bridge site selection. B) River width and depth alone do not provide a complete basis for site selection. C) Foundation safety is crucial but must be considered alongside hydraulics and bank stability.
Shortcut
Bridge site selection depends on river banks, depth/width, and foundations: select "All of the above".
Common mistake
Selecting a single site criteria factor without recognizing that all listed conditions are necessary.
Correct answer: D) All of the above