Question

In a siphon aqueduct, the worst condition of uplift on the floor occurs when ________

(a) the canal is full and the drainage empty with the water table at drainage bed

(b) the canal and drainage are flowing full

(c) the canal is empty and the drainage full with the water table at drainage bed

(d) the canal is full and the drainage empty with water table below the floor

I have been asked this question during an online interview.

I need to ask this question from Cross Drainage Work Design topic in portion Cross Drainage Work of Irrigation Engineering

Answer 1

The correct option is (c) the canal is empty and the drainage full with the water table at drainage bed

Easy explanation: In siphon aqueducts, the uplift due to water table acts where the bottom floor is depressed below the drainage bed. The maximum uplift under the worst condition is when there is no water flowing in the drain and the water table has risen up to drain bed.