反复循环荷载下考虑上覆土体压力软土次固结变形试验研究  

Experimental study on behavior of secondary consolidation of soft soils considering upper soil layers' stress under repeated cyclic loading

作　　者：陈志波[1,2,3] 孔秋平 朱俊高[5] 张升锋 CHEN Zhibo KONG Qiuping ZHU Jungao ZHANG Shengfeng(Department of Resources and Urban-Rural Construction, Fuzhou University, Fuzhou 350116, China Fujian Provincial Universities Engineering Research Center of Geological Engineering, Fuzhou 350116, China Key Laboratory of Geohazard Prevention of Hilly Mountains, Ministry of Land and Resources, Fuzhou 350116, China Fujian Yongqiang Geotechnical Engineering Co. Ltd., Longyan 364116, China Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering, Hohai University, Nanjing 210098, China Fujian Academy of Building Research, Fuzhou 350025, China)

机构地区：[1]福州大学资源与城乡建设系,福建福州350116 [2]地质工程福建省高校工程研究中心,福建福州350116 [3]国土资源部丘陵山地地质灾害防治重点实验室,福建福州350116 [4]福建永强岩土工程有限公司,福建龙岩364116 [5]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210098 [6]福建省建筑科学研究院,福建福州350025

出　　处：《中南大学学报（自然科学版）》2016年第10期3507-3514,共8页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(41102167)~~

摘　　要：采用不同原状软土,取循环荷载卸载时试样最小应力为原状软土上覆土体压力,进行反复循环荷载下的一维固结试验,研究软土的次固结变形特性。研究结果表明:在荷载循环过程中,初始最大预压荷载越大,软土次固结系数C_a越小;次固结系数随循环次数增大减小明显,当循环次数达20次以上时,减小逐步变缓;循环荷载越大,软土的次固结系数越大且减小越迅速。经35次循环荷载后,再加载时次固结系数C_a随再加荷载p_1增大而增大,且C_a与lgp_1呈线性关系;最大预压荷载越大、维持时间越长,再加载时次固结系数C_a越小。Based on one dimensional consolidation tests on soft soil samples, the influence of repeated cyclic loading on the secondary consolidation properties was investigated considering the upper soil layers＇ stress. The results show that during the loading cyclic stage, the secondary consolidation coefficient of soft soil C_a decreases with the increase of the largest preloading pressure. C_a also decreases significantly with the increase of the loading cycle number, while it decreases slowly after 20 cycles. The larger the cyclic loading is, the greater the C_a is, and it decreases more quickly. After 35 cycles, C_a increases with the increase of the reloading pressure p_1, and there is a linear relationship between Caand lgp_1. C_a also increases with the increase of the largest preloading pressure and its lasting time.

关 键 词：软土 地基工程 循环荷载 固结试验 次固结系数 

分 类 号：TU411[建筑科学—岩土工程]