波浪对海床作用的试验研究

采用波浪水槽模型试验的方法,研究波浪荷载作用下砂质和粉质海床的孔压响应问题。研究发现:与波浪理论的计算值相比,模型海床表面的动水压力测试值受填充样的影响;波浪荷载作用下,对于砂质海床,其内部超静孔压不会出现累积,而粉质海床孔压累积现象非常明显。结合试验数据,利用信号分析的方法,将不同的超静孔隙水压力增长模式分为3种,探讨波浪荷载作用下粉质海床的孔压发展机理。对土工布加固粉质海床进行模拟试验,结果表明:土工布可以显著地降低波浪荷载引起的粉质海床的超静孔隙水压力累积,起到防止海床液化的作用。

Experimental investigation on wave-induced response of seabed

Experimental investigation is conducted in a wave flume in order to identify the wave-induced response of sandy and silty seabed. Comparing with the theoretical pressure, the test results indicate that measured pressure on the surface of the model seabed is slightly affected by the soil fill. In a silty seabed, the excess pore pressure mounts distinctly due to the progressive wave, whereas there is no such phenomenon in a sandy seabed. The mechanism of pore pressure generation in a silty seabed is discussed using the experimental data. Three types of modes for excess pore pressure generation are developed by signal analysis. An improved method using geotextile is proposed to strengthen the silty seabed. The test results show that the excess pore pressure falls remarkably and that the silty seabed can be prevented from liquefaction by use of geotextile.