SIDE FRICTION ANALYSIS OF ROCK-SOCKETED PILE CONSIDERING DILATANCY OF STRUCTURAL PLANE
YE Guanbao1，2，MENG Minghui1，2，XING Haofeng1，2，LIU Zhikui3，HE Wenyong4
(1. Department of Geotechnical Engineering，Tongji University，Shanghai 200092，China；2. Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education，Tongji University，Shanghai 200092，China；3. College of Civil Engineering and Architecture，Guilin University of Technology，Guilin，Guangxi 541004，China；4. Guizhou Transportation Planning，Survey and Design Academy Co.，Ltd.，Guiyang，Guizhou 550001，China)
Abstract：The shear mechanism of pile-rock interface of rock-socketed pile includes sliding dilatancy and shear slipping；the sliding dilatancy causes the normal stress increase significantly. The method for calculating the side friction of rock-socketed pile proposed by Serrano did not consider the effect of pile-rock interface dilatancy，which makes it more conservative than the measured value. Based on the results of the structural plane shear tests under constant normal stiffness(CNS) condition，which fully consider the effect of lithology，pile diameter and construction on the mechanical characteristics of rock-socketed piles，and the quantified values of the normal stress increment produced by dilatancy are achieved；then Serrano?s method is modified by considering the quantified normal stress increment values. The analytical results show that，the side friction values calculated by the modified method exceed the values calculated by Serrano?s method；and the former are also closer to the field measured values. It is confirmed that the modified Serrano?s method is more reasonable.
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2013, Vol. 32 
