上海地区基坑底部粉质黏土回弹变形参数分析  

Statistical Analysis for Rebound Deformation Parameters of Silty Clay at Bottom of Deep Excavation in Shanghai

作　　者：楼晓明[1,2] 李德宁[1,2] 杨敏[1,2] 

机构地区：[1]同济大学岩土及地下工程教育部重点实验室,上海200092 [2]同济大学地下建筑与工程系,上海200092

出　　处：《同济大学学报（自然科学版）》2012年第4期535-540,共6页Journal of Tongji University:Natural Science

基　　金：国家自然科学基金(50978201)

摘　　要：根据压缩试验的回弹—再压缩曲线,得到了根据回弹指数及孔隙比计算回弹模量的理论公式.通过对大量上海地区相关土层勘察资料的统计分析,得到了上海地区⑤层、⑥层、⑧层粉质黏土回弹指数、压缩指数与塑性指数和比贯入阻力之间的线性关系.由于塑性指数和比贯入阻力不受取样扰动影响,可利用这些统计公式估算回弹指数,并结合上述理论公式进一步求得回弹模量.经多个实例验证,此方法精度可满足工程实践需要,且方便可行.研究结果可用于缺少回弹变形试验参数工程的回弹变形量验算.According to the rebound and recompression curve of compression test, the theoretical formulation to compute rebound modulus through rebound index and void ratio is given. The linear correlations of rebound index, compression index with plasticity index and specific penetration resistance for the silty clay of the fifth, sixth and eighth layer in Shanghai are observed according to a large number of survey data. Plasticity index and specific penetration resistance are not affected by sampling. Therefore, the rebound index can be obtained by means of the previous statistical formulation. Then the rebound modulus can be obtained through the theoretical formula. This method is proved to be precise and convenient for engineering practice by several instances. The results can be used for checking the rebound deformation inconditions of lacking rebound deformation parameters from tests.

关 键 词：回弹模量 回弹指数 压缩指数 塑性指数 比贯入阻力 

分 类 号：TU447[建筑科学—岩土工程]