孤立波对直立防波堤波浪渗流作用的解析计算

Analytical calculation of solitary wave-induced seepage effects on the vertical breakwater

浅水波浪在一定条件下可能以孤立波形态与近岸海工设施产生相互作用。该文基于水波反射理论和波浪渗流的Biot固结理论,应用特征函数法,推导了孤立波作用下直立防波堤的反射波速度势和波浪引起的海床内渗流压力分布的解析表达式,并据此计算了作用于直立防波堤底部的由孤立波渗流压力所致浮托力和倾覆力矩。计算结果表明海况与海床条件以及防波堤几何条件等因素的变化对孤立波引起的渗流浮托力和倾覆力矩均有一定影响。在一定条件下,对防波堤的孤立波渗流作用与孤立波直接作用量级相近。与微幅波理论相比,孤立波理论有效反映了浅水波非线性特征的影响。

In certain condition,the shallow water wave may emerge in solitary wave form,interacting with offshore structures. Based on wave reflection theory and Biot wave seepage consolidation theory,the analytical solutions of the reflected solitary wave potentials and the solitary wave-induced seepage pressures inside permeable elastic seabed are derived by applying the eigenfunction expansion approach,and the wave-induced lift force and overturning moment caused by the seepage pressure on the bottom of the vertical breakwater are accordingly calculated. The results show that the variation of sea and seabed conditions and breakwater geometry condition may have some influence on wave-induced seepage uplift force and overturning moment. The solitary wave-induced seepage effects may have the same order of magnitude as the direct horizontal wave effects. Compared with the results from small amplitude wave theory,the solitary wave theory can reflect shallow wave nonlinear effects.