水泥土融沉特性的试验研究  

Experimental study on thaw subsidence properties of cement-improved soil

作　　者：鲍俊安[1] 杨平[1] 张翔宇[1] 

机构地区：[1]南京林业大学土木工程学院,江苏南京210037

出　　处：《南京林业大学学报（自然科学版）》2013年第5期97-102,共6页Journal of Nanjing Forestry University：Natural Sciences Edition

基　　金：国家自然科学基金项目(51278251);南京地下铁道有限公司科研项目(2012;D3-XY-0001-1206)

摘　　要：为了研究水泥土融沉特性，对掺入不同比例水泥的南京地区典型黏土和砂土进行了融沉试验研究。结果表明：无论是黏土质还是砂土质水泥土，掺入比对融沉率的影响均与其对冻胀率的影响规律类似，融沉率随水泥含量增大而呈衰减性减小，并存在控制冻融的最佳水泥含量，南京地区典型黏土和砂土的最佳水泥掺入比分别为10％、5％，当采用最佳水泥掺入比时黏土和砂土的融沉率仅为不含水泥时的16．4％、18．5％；融化温度对最终融沉系数大小没有影响，但对最终融沉稳定时间有显著影响；黏土水泥土经过冻融后，其压缩系数增大31．1％～68．4％，而砂土经过冻融后，其压缩系数基本不变。综合分析可得：在土中掺入水泥可有效控制融沉，强制解冻不会增加融沉量但可大大加快融沉结束时间。In order to study the thaw subsidence properties of cement-improved soil, experimental research were carried out with two typical soils in Nanjing region, clay and sand mixed with the cement. The experiments show that the law that mixing ratio of cements has impact on the thaw subsidence is similar to the law on the frost heave, and the thaw sub- sidence coefficient of clay or sand cement-improved soil declines exponentially with mixing ratio of cement increasing. The optimal mixing ratio to of clay and sand in Nanjing region are 10% and 5%. The thaw subsidence coefficients are only 16.4% and 18.5% when the mixing ratio is the optimal mixing ratio. The melting temperature has no impact on coefficient of thaw subsidence, but observably impact on time of thaw subsidence. After clay cement-improved soil was frozen, the coefficient of compression increased by 31.1% - 68.4% while the coefficient of compression of sand cement- improved soil was invariant. By comprehensive analysis, mixing the cement into soil can control thaw subsidence. The force thawing doesn＇t increase the magnitude of thaw subsidence but can reduce by a large margin the time of thawing.

关 键 词：水泥土 水泥掺入比 融沉 压缩系数 

分 类 号：TU445[建筑科学—岩土工程]