冻融循环对改良软粘土压缩特性的影响  

The effect of freeze-thaw cycles on compressive properties of improved soft clay

作　　者：胡莫珍 谈云志[1,2] 吴翩[2] 杨爱武[1] 

机构地区：[1]天津城建大学土木工程学院,天津300384 [2]三峡大学土木与建筑学院,湖北宜昌443002

出　　处：《广西大学学报（自然科学版）》2015年第1期208-212,共5页Journal of Guangxi University（Natural Science Edition）

基　　金：国家自然科学基金资助项目(51009084);天津市软土特性与工程环境重点实验室开放基金(2012SCEEKL007)

摘　　要：为了研究改良土的长期力学性能,以为改良土地基处理工程的施工提供可靠技术指导,制备了初始含水率不同的试样,开展了水泥改良软粘土的压缩试验,探讨了冻融循环作用对改良土压缩性能的影响。结果表明,在多次冻融循环作用后,改良土的压缩系数会有不同幅度的增加;饱和度会影响改良土的压缩性能,且饱和度越高则压缩性越差。试样压缩模量的最终损失率随含水率的增加而增大,含水率高于32.5%时压缩模量损失率急剧增大。因此,考虑到土样的后期强度损失,地基处理工程中此类改良粘土填筑含水率应尽量偏低,不宜超过32.5%。In order to study the long-term mechanical properties of improved clay and to provide reliable technical guidance for foundation treatment,some specimens of cement-improved soft clay were made with different initial water content.Unconfined compressive strength test was carried out to search for the influence of freeze-thaw cycles on the compressive properties of the improved clay.The results show that disregarding of the water content,the compression coefficient was increased to different extent after subjected to repeating freeze-thaw cycles.The level of saturation had effect on the compression properties of improved soft clay.Moreover,the compression properties decreased when the saturation level grew.Along with the increase of water content,the final loss ratio of compression modulus went up,which rose rapidly if the water content was above 32.5%.Taking later strength loss of specimens into account,such improved clay had better not have low water content,which preferably was not over 32.5% in foundation treatment.

关 键 词：冻融循环 软粘土 压缩性 水泥改良 

分 类 号：TU4[建筑科学—土工工程]