Ultimate bearing capacity of coralline sand foundation under high internal friction angle
CAO Zhenzhong1，LU Xiulian1，MO Hongyan1，QIN Zhiguang2，SHI Yuanqi1
(1. Guangxi Key Laboratory of Geomechanics and Geotechnical Engineering，Guilin University of Technology，Guilin，Guangxi 541004，China；2. CCCC Key Laboratory of Environment Protection and Safety in Foundation Engineering of Transportation，
Guangzhou，Guangdong 510230，China)
Abstract：The results of classical ultimate bearing capacity calculations developed by Terzaghi et al. and the results of in-situ plate load tests show that the ultimate bearing capacity of coralline sand foundations can exceed up to 4 000 kPa，which differs significantly from its general understanding of low bearing capacity. Since the coralline sand has high internal friction angle，based on the classical limit equilibrium calculation model，the influence of internal friction angle on the size of general shear failure range is analyzed to clarify the mechanism and conditions of high ultimate bearing capacity of coralline sand. Through the in-situ plate load test of the coralline sand sites at the Port of Sudan before and after treatment，the phenomenon of high ultimate bearing capacity of coralline sand foundation is confirmed. The analysis and results indicate that under the high internal friction angle and general shear condition，the coralline sand foundation could have a larger shear failure depth and wider shear failure range，which result in higher ultimate bearing capacity according to the ultimate equilibrium equations. General shear failure is a prerequisite for high ultimate bearing capacity of coralline sand foundation，and the foundation treatment of layered dynamic compaction and layered dredging can meet this condition. The actual shear failure range of coralline sand foundation may differ greatly from that of classical ultimate bearing capacity calculation method，and the ultimate bearing capacity calculation formula applicable for coralline sand is necessary for further study.
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2023, Vol. 42 
