波浪导致粉质土海床破坏过程试验研究  

An Experimental Study on Wave-Induced Failure Process in Silty Bottom Bed

作　　者：杨忠年[1] 贾永刚[1,2] 张琳[1] 刘晓磊[1] 单红仙[1,2] 

机构地区：[1]中国海洋大学环境科学与工程学院,山东青岛266100 [2]中国海洋大学海洋环境与生态教育部重点实验室,山东青岛266100

出　　处：《中国海洋大学学报（自然科学版）》2015年第5期75-81,共7页Periodical of Ocean University of China

基　　金：国家自然科学基金项目(41072215;40876042);国家高技术研究发展计划项目(2008AA09Z109)资助

摘　　要：以黄河三角洲粉质土底床为研究对象,通过水槽模拟试验,研究了不同波高波浪荷载作用下底床的破坏过程与特点。研究发现,波浪导致粉质土底床在孔压累积和剪应力耦合作用下由表及里破坏;在波浪作用下粉质土底床破坏过程分为土体扩展过程和土体恢复过程,在扩展过程中,破坏土体与波浪同步振荡,边界不断扩展直至极限深度。在恢复过程中,破坏土体振荡由深到浅逐渐停止,稳定后出现细粒土夹层;破坏土体的长度﹑深度和体积间呈幂函数关系,破坏土体的范围主要由深度决定;波浪作用停止后,动力固结不足的原破坏土体在新一轮波浪作用下可能会再次破坏;基于极限平衡理论对波致粉质土底床的破坏深度范围进行了初步的预测,并与试验结果进行了对比分析。Silty bottom bed in estuary of the Yellow River is studied in this paper. The differences of wave he-ight were applied in a laboratory flume to study failure process of silty bottom bed under wave ac- tion, and the characteristic of the process. Results show that coupled accumulative pore pressure and shear stress make silty bottom bed fail from the surface to the inner under wave action. Failure processes of wave-induced silty bottom bed include expansion process and restore process. Failure soil mass is in perfect synch with wave surges, and the boundary extends to the maximum of failure depth in the expanding. Failure soil mass stops oscillating fr-om deep to shallow, and fine grained soil interlay occurs in the failure area after it stabilizes. The relationships among the length, depth and volume of failure soil are found to follow a power function, and the depth beco-mes the chief factor in deciding the scale of failure. After wave action stops, original failure soil mass of lacki-ng dynamic consolidation may reactive under another wave action. Based on the theory of limit equilibrium, th-ere is a preliminary forecasting for the depth range of destructive silty bottom bed under wave action, then to compare with test results.

关 键 词：波浪作用 水槽试验 粉质土底床 破坏过程 破坏深度 

分 类 号：TU431[建筑科学—岩土工程]