不同循环荷载作用下软黏土动力特性对比试验研究  

Comparative Experimental Study on Dynamic Characteristics of Soft Clay under Different Cyclic Loads

作　　者：刘建民 付海清[1] 郭婷婷 张广成[1] 谷川[2] 王冰 宋文智 LIU Jianmin;FU Haiqing;GUO Tingting;ZHANG Guangcheng;GU Chuan;WANG Bing;SONG Wenzhi(Shandong Earthquake Agency, Ji’nan 250014, Shandong, China;College of Architecture and Civil Engineering, Wenzhou University, Wenzhou 325035, Zhejiang, China;Shandong Electric Power Engineering Consulting Institute Corp., Ltd, Ji’nan 250013, Shandong, China;China MCC20 Group Corp., Ltd, Shanghai 201999, China)

机构地区：[1]山东省地震局,山东济南250014 [2]温州大学建筑与土木工程学院,浙江温州325035 [3]山东省电力工程咨询院,山东济南250013 [4]上海二十冶建设有限公司,上海201999

出　　处：《地震工程学报》2020年第4期973-981,共9页China Earthquake Engineering Journal

基　　金：国家自然科学基金项目(51578426);山东省自然科学基金(ZR2014DQ022);山东省地震局青年基金项目(JJ1806Y);山东省地震局重点基金项目(JJ1801)。

摘　　要：研究交通循环荷载作用下路基软黏土的长期沉降和动力力学性质对路基设计具有重要意义。本文通过GDS动三轴实验,研究(不排水条件下)振动波形、排水条件以及动应力比三因素对于软黏土动应变和动孔压的影响。试验结果显示:排水条件对饱和软黏土的动应变和动孔压影响最大,在部分排水条件下动孔压逐渐消散,动应变迅速发展。振动波形对软黏土动应变和动孔压影响较大,单向纯压半正弦波作用下软黏土的动应变和动孔压较容易达到最大值。在较少的振次内动应力比对孔压影响较大,但在归一化的孔压模型中,动应力比对孔压影响较小。通过以上分析,本文建立包含循环振次和纯压因素的孔压增长模型。Investigation of long-term settlement and dynamic mechanical properties of soft clay under cyclic loads is important to its subgrade design.In this study,we determined the effects of vibration waveform,drainage condition,and dynamic stress ratio on the dynamic strain and dynamic pore pressure of soft clay under undrained condition through GDS dynamic triaxial test.Results show that the drainage condition exhibits the most serious influence on the dynamic strain and dynamic pore pressure of saturated soft clay.Under the condition of partial drainage,the dynamic pore pressure gradually dissipates and the dynamic strain develops rapidly.The vibration waveform also influences the dynamic strain and pore pressure of soft clay,and these parameters easily reach the maximum value under the action of unidirectional pure pressure semi-sine wave.The dynamic stress ratio has a great effect on pore pressure under few vibration times.However,the dynamic stress ratio minimally affects pore pressure in the normalized pore pressure model.Through the above analysis,a pore pressure growth model including the indices of cyclic vibration time and pore pressure,was established.

关 键 词：动孔压 动应变 动三轴 孔压模型 

分 类 号：TU4[建筑科学—土工工程]