EXPERIMENTAL STUDY OF BEARING BEHAVIOUR OF COMPOSITE FOUNDATION WITH RAMMED SOIL-CEMENT TAPERED PILES
HE Jie1，2，LIU Jie1，ZHANG Keneng2，WU Youping1，CAO Zuoxing1
(1. School of Civil Engineering，Hunan University of Technology，Zhuzhou，Hunan 412007，China；
2. School of Geosciences and Info-Physics，Central South University，Changsha，Hunan 410083，China)
Abstract：Aiming to composite foundation with rammed cement-soil piles in soft ground，the contrast tests for a group of composite foundation with 9 rammed cylindrical cement-soil piles and three groups of composite foundation with 9 rammed tapered cement-soil piles are performed in laboratory，respectively. The relationships of average settlement-load and average pile-soil stress ratio-load，and the load transferring law of four groups of composite foundations with rammed cement-soil piles under the same condition are studied. The test results indicate that：(1) The differential settlement between pile and soil can be adjusted by rammed tapered cement-soil pile；and the ground settlement can be decreased and its bearing capacity can be enhanced obviously. (2) The bearing behaviour of rammed tapered cement-soil piles in the composite foundation can be exerted by enhancing its taper. The average pile-soil stress ratio of composite foundation with rammed tapered cement-soil piles is higher than that of composite foundation with rammed cylindrical cement-soil piles. (3) With the increase of the taper， the decay rate of axial force in rammed cement-soil tapered pile is increased and the load transferring depth is reduced. The bearing characteristic of rammed tapered cement-soil pile is better than that of rammed cylindrical cement-soil pile. The taper is bigger，the pile properties can be exerted more fully.
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2012, Vol. 31 
