天然沉积结构性软土的超载预压变形性状试验  

Experimental Study on Deformation Behavior of Surcharge Preloading for Soft Natural Clays

作　　者：曾玲玲[1] 陈福全[1] 郭立群[2] 

机构地区：[1]福州大学土木工程学院,福建福州350108 [2]华侨大学土木工程学院,福建厦门361012

出　　处：《华侨大学学报（自然科学版）》2012年第4期435-439,共5页Journal of Huaqiao University(Natural Science)

基　　金：国家自然科学基金资助项目(41102168)

摘　　要：通过对天然沉积土进行常规一维压缩试验和不同有效超载比下的超载预压一维压缩试验,分析超载预压作用下天然沉积土压缩变形性状.研究结果表明:不同有效超载比预压作用下的竖向应变压缩历时曲线特征不同,预压过程主固结阶段的曲线斜率随着预压荷载的增大而增大,而次固结阶段的斜率却随着预压荷载的增大而减小;不同超载比预压作用后,超载作用延缓了次固结压缩变形发生的时间,超载比越大延缓的时间越长;延缓时间过后次固结压缩变形将重新发展,且随着对数时间的发展次固结系数呈先增大后趋于稳定的变化趋势.In order to investigate the deformation behavior of natural clays under surcharge preloading, the one-dimensional compression tests were conducted with different surcharge pressure ratios, different preloading durations and unloading durations. The test results indicate that： the curve between vertical strain and consolidation time varies with surcharge pressure ratio; with the increase of surcharge pressure, the slope of the curve increases during primary consolidation; decreases during the secondary consolidation, the larger the surcharge pressure ratio causes the longer delayed duration; when the consolidation time exceeds the delayed duration, the secondary consolidation develops, and the coefficient of secondary consolidation increases initially and then stabilizes with time.

关 键 词：超载预压 天然沉积土 结构性 压缩试验 变形规律 

分 类 号：TU411[建筑科学—岩土工程]