南宁膨胀土的次固结特性试验研究  

Test Study on Secondary Consolidation Characteristics for Nanning Expansive Soil

作　　者：曾庆国[1] 张春顺[1] 肖宏彬[1] 

机构地区：[1]湖南工业大学岩土工程研究所,湖南株洲412008

出　　处：《公路工程》2008年第1期10-13,共4页Highway Engineering

基　　金：国家自然科学基金资助项目(50378097)

摘　　要：针对非饱和及饱和南宁膨胀土进行了一系列室内试验研究,探讨了该膨胀土样的非线性流变特性。试验结果表明:一方面,对于一定含水率的非饱和膨胀土,在加荷初期2 h内,随荷载增加,应变迅速发展;当施加的初始荷载较小时,6 h后,试样应变随时间呈衰减趋势;当施加的初始荷载较大时,6 h后,试样应变呈现非衰减趋势,且含水率越大,非衰减趋势愈明显;饱和膨胀土样的e—lgt、e—lgp曲线与荷载是有关的;预压饱和土样的线胀率大约是无预压饱和土样线胀率的1倍。研究成果在理论学习及地基处理等方面都具有重大意义。Based on series of indoor tests for unsaturated and saturated Nanning expansive soils, properties of non-liner rheological characteristics of the expansive soils have been researched in this paper, The test results show as follows： on the one hand, the strains of the unsaturated soils with same water content develop rapidly in two hours after being loaded ;6 hours later, to those soil samples under low initial loads, attenuation trend of the strains with lapse of time is to be found while to those soil samples under big initial loads, non-attenuation trend the strains with lapse of time is to be found, and moreover the greater the water contents, the more obvious the non-attenuation trend ; On the other hand, as for the saturated soil samples, e-lgtand e-lgpcurves have some relation with load processes; preloaded saturated soils＇ percent swelling is about one time bigger than that of the free expansive soils＇. The study result is very important and meaningful in theory learning and foundation designs.

关 键 词：膨胀土 次固结 非衰减 分级加载 线胀率 

分 类 号：TU443[建筑科学—岩土工程]