随机荷载作用下饱和松砂的动力特性试验研究

Experimental Research on Dynamic Characteristics of Saturated Loose Sand Under Random Loading

随机波浪荷载是海洋结构物设计中需考虑的主要荷载,根据波浪的特点,采用线性波浪叠加法生成随机波,形成随机加载序列。应用CKC多功能应力路径三轴仪在不同围压下,分别对饱和松砂试样施加随机荷载和相应的代表波荷载,通过正序和逆序随机加载研究随机荷载波形对砂土动力特性的影响。研究结果表明,与代表波荷载相比,砂土在随机荷载作用下孔隙水压力和轴向应变的变化模式不同,试样达到液化的时间明显减少,随机波正序和逆序加载对于砂土动力响应的影响不大。

Random wave loading is the main load needing to be considered when designing offshore structures .According to the features of the waves ,random waves were generated with the linear wave superposition method and random loading trains were recorded .Random wave loading and its corresponding representative wave loading were applied to saturated loose sand samples at different confining pressures using CKC multi-functional stress path triaxial apparatus respectively . The influence of random wave loading shapes on the dynamic characteristics of the sand was examined through applying random loading in ascending and descending order .The experimental results reveal that the changing patterns of pore pressure and axial strain in soil samples under random wave loading are different from those under the representative wave loading ,and the time to reach liquefaction is significantly reduced .Loading sequence of random waves has no obvious impact on dynamic behavior of the sand .