冻融循环作用对桩锚支护深基坑的土体材料强度参数影响试验研究  

Freezing and Thawing Cycle for Effecting on Strength Parameters of Soil for Deep Excavation by the Pile-anchor Support System

作　　者：董天文[1,2] 付海龙[3] 周宏源 杜东宁[2] 

机构地区：[1]辽宁省交通高等专科学校,辽宁沈阳110122 [2]辽宁工程技术大学,辽宁阜新123000 [3]东北大学,辽宁沈阳110004

出　　处：《辽宁省交通高等专科学校学报》2015年第5期5-8,共4页Journal of Liaoning Provincial College of Communications

基　　金：辽宁省交通高等专科学校首届优秀人才杰出专业(学科)带头人成长支持计划研究项目(YXRC-2012-03)

摘　　要：季节性冻土地区的土材料在冻融循环作用后的强度参数对深基坑支护体系的安全性影响显著。在季节性冻土地区深基坑支护稳定性设计和施工中,考虑冻融循环作用后的土材料抗剪强度具有一定的实际意义。采用直剪试验方法对冻融循环作用前后土材料强度参数进行研究,绘制剪应力与剪切位移关系曲线,抗剪强度与垂直压力关系曲线,结合强度曲线计算得到内摩擦角及黏聚力。分析表明:冻融循环结束后,土体的最大剪应力比冻融循环前降低;土体的抗剪强度参数,内摩擦角在冻融循环作用结束后减小,黏聚力有所增加。In seasonal frozen earth, the strong parameters of soil material are important for the stable security of the support system of deep excavation after freeze-thaw cycle. So it has the engineering significance to consider the strong parameters of soil material after freeze-thaw cycle. The direct shear test was performed to investigate the shear changes of earth which is under the effects of the freeze-thaw cycle, drawn shear-shear-shear displacement curves and shear strength-vertical stress curves, and the shear strength parameters, c and, can be worked out relating to the shear strength curve. The result of testing and researching show that the soil＇s maximum shear after freeze-thaw cycle is lower than that before the test. The soil＇s shear strength parameters, c has decreased after the test, however increases to some extent.

关 键 词：季节性冻土 冻融循环 直剪试验 抗剪强度 

分 类 号：TU432[建筑科学—岩土工程]