Prototype tests on micro-steel pipe piles as retaining structures
XIANG Bo1, 2, MA Jian-lin1, HE Yun-yong2, ZHOU Li-rong1
1. School of Civil Engineering, Southwest Jiaotong University, Chengdu 610031, China; 2. Sichuan Provincial Transport Department Highway Planning, Survey, Design and Research Institute, Chengdu 610041, China
Abstract：The application of micro-steel pipe piles as a new retaining structure is seriously restricted for the lack of systematic studies. Through the surcharge load tests on three kinds of different prototype structures, the data such as pile-soil deformation, pile strain and earth pressure are measured from the loading to the ultimate failure. Based on this, the stress and deformation laws of the retaining structures are summarized, the effects of the row number, distance between two rows and pile spacing on the bearing capacity are analyzed, and the earth pressure ratios of bearing thrust of each row of piles are obtained. The conclusions provide more systematic basic data for the theoretical analysis and engineering applications of micro-steel pipe piles as retaining structures.
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