Drop water is one kind of common channel system structures,it mustexist that the transition from supercritical flow to subcritical flow when water pass through the gap of drop water.

if we could use the drop water to gauge water accurately, it might not only reduce the loss of head caused by gauging facility of irrigation system, but also might save a lot of additional construction costs for gauging water and also reduce the project quantity, so it is one kind of economical and conv.

Discussion on application of square-shaped vertical drop;

Numerical simulation of the analysis of possibility of water inrush through fault;

Solid-liquid coupling study on water inrush through faults in coal mining above confined aquifer;

But during the shallow coal seam mining,the Quaternary pore water has local direct hydraulic connection,and the focal point of to keep away is gob water and fault conducted water,because of calamities bring about may be .