Uplifting behavior and bearing capacity of plate anchors in sand
ZHANG Xin1, 2, YUE Jin-chao1, LIU Ming-liang3, LIU Han-dong2
1. School of Water Conservancy and Environment, Zhengzhou University, Zhengzhou 450001, China; 2. Institute of Resources and Environment, North China University of Water Resources and Electric Power, Zhengzhou 450011, China; 3. Henan Electric Power Survey & Design Institute, Zhengzhou 450007, China
Abstract:The deformation mechanism of sand around plate anchors during uplifting is essentially important for the reliable prediction of their ultimate bearing capacity in sand. First, a series of model tests are conducted. The digital image correlation method is used to measure the sand deformation fields during uplifting of anchors. The deformation fields show that a pair of shear zones accompanied by dilatancy are formed. The stress level, friction angle and dilatancy angle control the shape of the failure surface, thus affecting the bearing capacity of the plate anchors in sand. A prediction model for uplift force is developed based on the sand deformation mechanism around an uplifting plate anchor. The relationship among the dilatancy angle, the relative density and stress level established by Bolton is introduced to develop the theoretical formula. The comparison between the theoretical and test results is conducted. The theoretical results show good agreement with the test results.
张昕, 乐金朝, 刘明亮, 刘汉东. 砂土中锚板的抗拔机理与承载力计算模型研究[J]. 岩土工程学报, 2012, 34(9): 1734-1739.
ZHANG Xin, YUE Jin-chao, LIU Ming-liang, LIU Han-dong . Uplifting behavior and bearing capacity of plate anchors in sand. Chinese J. Geot. Eng., 2012, 34(9): 1734-1739.
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