A NEW CALCULATION METHOD FOR LARGE-DIAMETER-TUBULAR-PILE BEARING CAPACITY
LI Yiwen1，LI Boan2，LI Jianqiang2，ZHOU Jian1
(1. Institute of Geotechnical Engineering，Zhejiang University，Hangzhou，Zhejiang 310058，China； 2. Zhejiang Design Institute of Water Conservancy and Hydro-electric Power，Hangzhou，Zhejiang 310002，China)
Abstract：Based on the imperial college pile(ICP) method，a new method is proposed to calculate the bearing capacity of large-diameter-tubular-pile，in which the contribution of soil plug is considered. However the inner pile friction is not taken into account due to the small value，not full-length distributed and conservative consideration. In this approach，the end resistance is the average value of tip resistance from the pile tip to the depth of 2 times of the pile diameter. In view of the unpopularity of ring shear test，the peak value of direct shear test is used for the friction angle of the interface by amplification of 1.2，which is verified through test results. The radial effective stress is very important in bearing capacity calculation，and a simplified method with a few parameters is put forward. This new approach is much simpler than ICP method，and could have satisfactory estimations if compared with α-method，Randolph methods and V&F method. The test results prove that the new method is reliable.
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2012, Vol. 31 
