Experimental study on anisotropy of saturated coral sand under complex stress conditions
MA Wei-jia1, QIN You1, WANG Chang-de1, CHEN Guo-xing1,2
1. Institute of Geotechnical Engineering, Nanjing Tech University, Nanjing 210009, China; 2. Civil Engineering and Earthquake Disaster Prevention Center of Jiangsu Province, Nanjing 210009, China
Abstract：Anisotropy is the inherent property of coral sand. A series of undrained monotonic shear tests are carried out on the saturated Nansha coral sand by using the GDS hollow cylinder torsional shear apparatus. The effects of consolidation stress direction angle α0 and monotonic loading direction angle αm on the undrained response of saturated coral sand are investigated. The test results show that α0 and αm have significant influences on the undrained response of saturated coral sand. The undrained response characteristics of coral sand will become more complex under the coupling effects of α0 and αm. For all the test conditions considered, the excess pore water pressure ue of saturated coral sand presents contraction first and then dilatancy trend. The change of the shear resistance (SPT) and its effective angle (${{{\phi }'}_{\text{PT}}}$) mobilized at the phase transformation state along with αm are significantly different for various α0. There is a unique linear correlation between SPT and the dimensionless parameter β, which is a cosine function with α0 and αm as variables. With the increase of the generalized shear stress qg, obvious strain hardening phenomenon can be observed for the samples.
马维嘉, 秦悠, 王常德, 陈国兴. 复杂应力条件下饱和珊瑚砂各向异性试验研究[J]. 岩土工程学报, 2022, 44(3): 576-583.
MA Wei-jia, QIN You, WANG Chang-de, CHEN Guo-xing. Experimental study on anisotropy of saturated coral sand under complex stress conditions. Chinese J. Geot. Eng., 2022, 44(3): 576-583.
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