FEM analysis of bearing behavior of large-diameter socketed piles
HUANG Sheng-gen1, ZHANG Xiao-wei2 , LIU Wei-bo3
1. Faculty of Engineering, China University of Geosciences, Wuhan 430074, China; 2. Henan Provincial Communications Planning Surveying & Designing Institute, Zhengzhou 450052, China; 3. Zhengzhou Municipal Engineering Corporation, Zhengzhou 450052, China
Abstract：According to the test data of a socketed pile, the bearing behavior of large-diameter socketed piles is analyzed systematically with FEM, and the sinusoid is used to simulate the interface of pile and rock. According to the computed results, the following conclusions are drawn: (1) In the same settlement of pile heads, the hole walls are rougher, the capacities of piles are higher. (2) The friction resistances of small diameter plies along pile shafts are unimodal distribution, and that of large-diameter plies are bimodal distribution. The friction resistances decrease with the increasing diameters. (3) In the soft rock, the bearing capacities of piles increase with <>hr/<>d; in the medium hard rock, the bearing capacities remain constant when <>hr/<>d reaches 5; in the hard rock, the bearing capacities remain constant when <>hr/<>d reaches 3. (4) The ratio of base resistances to the bearing capacities (<>Qb/<>Qu) decrease with the increasing <>hr/<>d, and the effect of the ratio of socketed depth to diameter of pile (<>hr/<>d) on the <>Qb/<>Qu is different with the strength of rock.
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