摘要
采用应力-应变控制式三轴仪对福州市区某基坑影响范围内典型饱和软土进行了一系列应力路径试验,以研究受基坑开挖和支护结构作用影响的土体卸、加载应力-应变特征。对室内正常固结和相同围压K0固结的试样剪切试验结果进行了比较,表明二者在变形和强度上均存在较大差异。基于K0固结剪切试验结果,求出了邓肯-张模型参数,提出了该模型各参数的验证方法。同时,与室内正常固结试验确定的模型参数进行了对比,说明部分参数之间存在着较大差异,也决定了二者应力-应变关系上的差异,建议以K0固结试样进行三轴加、卸载试验确定邓肯-张模型参数,以满足该模型在基坑工程数值模拟分析中的需要。试验得到的典型软土的邓肯-张模型参数,可供福州市区或相似地层条件下基坑工程数值模拟时参考。
A series of stress path tests on typical soft soils（silt and organic silty clay） in the influence range of foundation pit in Fuzhou city were conducted by using triaxial apparatus with stress and strain control in order to research the stress-strain behaviours of unloading and loading caused by excavation and retaining structure of foundation pit.Compared with the results of triaxial tests between normal consolidation and K0 consolidation samples in the same confining pressure,it is indicated that there are large differences in deformation and strength.Based on the results of K0 consolidated triaxial tests,Duncan-Chang parameters were figured out and the methods of certification of each parameter in the model were put forward.At the same time,comparison with model parameters obtained by normal consolidation samples showed that some parameters had significant difference;and they decided the difference of stress-strain relationship.Duncan-Chang model parameters were suggested to obtained through triaxial loading and unloading test by K0 consolidation samples for the sake of satisfying numerical simulation analysis of foundation pit engineering.Duncan-Chang parameters of typical soft soils offered by the tests can be referred to numerical simulation of foundation pit engineering in Fuzhou city or other similar strata sites.
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2011年第11期3249-3257,共9页
Rock and Soil Mechanics
基金
福建省自然科学基金重点资助项目(No.D0720001)
福州大学科研启动基金资助项目(No.022279)
