A testing method for shear-wave velocity and relative density of cohesionless soil using bending-element technique
WANG Yunlong，CAO Zhenzhong，YUAN Xiaoming，CHEN Longwei
(Key Laboratory of Earthquake Engineering and Engineering Vibration，Institute of Engineering Mechanics，China Earthquake Administration，Harbin，Heilongjiang 150080，China)
Abstract：Shear-wave velocity and relative density are important parameters to assess the properties of cohesionless soil. To measure the shear wave velocity of gravelly soil，a combined test system of shear-wave velocity and relative density was developed. The system was established on a specific steel bearing cylinder combining bending-element technique，and then applied on soil samples with different relative densities prepared by a vertically vibrating table. The first-arrival time of shear-wave in bending-element technique is corrected. The system is designed to test shear-wave velocity of gravel with maximum particle diameter less than 50 mm，and then to build relationships of shear-wave velocity with respect to relative density of cohessionless soil. Four types of samples，i.e.，standard sand samples，granite samples，60% gravel content samples constituting of standard sand and granite，and samples prepared according to the mean grading of gravelly soil that liquefied in Wenchuan earthquake，are tested and the results indicate that shear-wave velocity of gravelly soil is large than sand under same relative density. Shear-wave velocity of gravelly soil increases exponentially with respect to increasing relative density. Comparing to GDS apparatus，the testing shear-wave velocity of gravelly soil are similar yet the design system is more applicable and more convenient.
汪云龙，曹振中，袁晓铭，陈龙伟. 基于弯曲元技术的无黏性土剪切波速与相对密度联合测试方法[J]. 岩石力学与工程学报, 2016, 35(S1): 3418-3423.
WANG Yunlong，CAO Zhenzhong，YUAN Xiaoming，CHEN Longwei. A testing method for shear-wave velocity and relative density of cohesionless soil using bending-element technique. , 2016, 35(S1): 3418-3423.
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2016, Vol. 35 
