风浪作用下库岸孔隙水压力响应试验研究

Experimental study on wind wave induced pore pressure response in reservoir bank

大多数水库都存在库岸坍塌问题,库区风浪波高明显高于成库前,风浪对库岸边坡稳定具有重要的影响.采用线性波和椭圆余弦波进行波浪水槽试验.结果表明,库岸内孔隙水压力随着波高、周期、水深的增大而增大,孔隙水压力沿库岸水平和垂直方向衰减速率不一致,浅层衰减较快,深层衰减较慢或已趋于稳定;黏土库岸浅层相应位置的孔压比沙土中的大,沿深度方向黏土中的孔压衰减较快,沙土库岸底层中相应位置的孔压比黏土中的大;沙土库岸内,线性波作用下孔隙水压力较大.不同波况作用下,孔隙水压力差值随波高增大而减小,随周期增大而增大,随水深增大其变化很小.

The majority of reservoirs have the bank collapsing problem. Wave height has the very big enhancement after the reservoirs are formed. Waves have the important influence on the bank slope stability. Wave flume model tests were carried out using linear wave and cnoidal wave theories. The results show that the pore water pressure of reservoir banks increases with the increase of wave height, period and water depth. The damping rates of the pore water pressure differ from horizontal and vertical directions. The bore water pressure is gone faster in decay at shallow depth and slower or tends to be stable at bottom depth. The pore water pressure in clay reservoir bank is greater than the same point in sand bank and it is gone faster in decay in shallow depth; however, the pore water pressure in the bottom of the sand reservoir bank is larger than that that in the clay bank. In sand reservoir bank, the pore water pressure by action of linear wave is larger than that by action of cnoidal wave. In different wave conditions, the pore water pressure decreases with the increase of wave height, and increases with the increase of the wave period. However, there is a very small change with the increase of water depth.