1. Department of Geotechnical Engineering, Tongji University, Shanghai 200092, China; 2. Key Laboratory of Geotechnical and Underground Engineering of the Ministry of Education, Tongji University, Shanghai 200092, China
Abstract:The small-strain shear modulus plays an important role in the calculations of ground seismic response and deformation in deep excavations. The values of the small strain shear modulus G0 of Shanghai soils by field and laboratory tests are investigated and compared, and empirical formulas are proposed to predict the values of G0. The results indicate that G0 mainly depends on the soil type, void ratio and mean confining pressure. The values of G0 from field tests are considerately higher than those from laboratory tests. The correlation between the small strain shear moduli from field and laboratory is also proposed. The numerical analysis is also carried out to calculate the deformation in a deep excavation in Shanghai. The small strain hardening model (HSS) is used, together with the measured small strain shear modulus. The values of G0 are essential for the deformation of the excavation, and the predicted deformation using the G0 value from field measurement is more accurate than that using the laboratory data based on the measured deformation in the excavation.
陈少杰, 顾晓强, 高广运. 土体小应变剪切模量的现场和室内试验对比及工程应用[J]. 岩土工程学报, 2019, 41(S2): 133-136.
CHEN Shao-jie, GU Xiao-qiang, GAO Guang-yun. Comparison and application of small strain shear moduli from field and laboratory measurements. Chinese J. Geot. Eng., 2019, 41(S2): 133-136.
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