Abstract：Base on indoor model experiments of mouth-closed step cross-section and constant cross-section pipe piles performed in foundation pit，the load transfer characteristics of both kinds of mouth-closed pipe piles were studied by comparing horizontal load-settlement curves，horizontal critical load and bending moment distribution of piles. Results of test show that horizontal load-settlement curves change slowly of both kinds of piles. Horizontal bearing capacities of step cross-section pipe piles are higher than constant cross-section pipe piles and there are close relation to average diameters of both kinds pipe piles. Horizontal critical bearing capacity per unit volume has increased by different degrees with improvement of segmentally cross-section ratio. Moreover，to step cross-section pipe piles，there are two bending moment extreme on pile and bending moment extreme on small diameter pipe has declined with the improvement of segmentally cross-section ratio. Finally，it is very obvious that step cross-section pipe pile is more reasonable than constant cross-section pipe pile in bearing characteristics because the bending moment has been improved greatly on small diameter pipes.
杨庆光，田 捷，刘 杰，王亚辉. 闭口阶梯型管桩水平承载性状模型试验研究[J]. 岩石力学与工程学报, 2015, 34(S2): 4412-4417.
YANG Qingguang，TIAN Jie，LIU Jie，WANG Yahui. MODEL TEST STUDY OF HORIZONTAL BEARING CHARACTERISTICS OF MOUTH-CLOSED STEP CROSS-SECTION PIPE PILE. , 2015, 34(S2): 4412-4417.
MATLOCK H. Correlations for design of laterally loaded piles in soft clay[C]// Proceedings of Second Annual Offshore Technology Conference. Houston：[s.n.]，1970，(1)：577-594.
[2]
REESE L C，WELCH R C. Lateral loading of deep foundations in stiff clay[J]. Journal of the Geotechnical Engineering Division，1975，101(7)：633-649.
[3]
王建华，陈锦剑，柯学.水平荷载下大直径嵌岩桩的承载力特性研究[J].岩土工程学报，2007，29(8)：1194-1198.(WANG Jianhua，CHEN Jinjian，KE Xue. Characteristics of large diameter rock-socketedpiles under lateral loads[J].Chinese Journal of Geotechnical Engineering，2007，29(8)：1194-1198.(in Chinese))
[4]
陈祥，孙进忠，蔡新滨.基桩水平静载试验及内力和变形分析[J].岩土力学，2010，31(3)：753-759.(CHEN Xiang，SUN Jinzhong，CAI Xinbin. Horizontal static loading test and analyses of internal force and distortion on single pile[J]. Rock and Soil Mechanics，2010，31(3)：754-759.(in Chinese))
[5]
王伯慧，上官兴.中国钻孔灌注桩新技术[M].北京：人民交通出版社，1999：37-39.(WANG Bohui，SHANGGuanxin. New technology of bored pile in China[M].Beijing：China Communication Press，1999：37-39.(in Chinese))
[6]
刘汉龙，张建伟，彭劼.PCC 桩水平承载特性足尺模型试验研究[J].岩土工程学报，2009，31(2)：161-165.(LIU Hanlong，ZHANG Jianwei，PENG Jie. Full-scale model test on behavior of cast-in-place concrete pipes with large diameter under lateral loads[J]. Chinese Journal of Geotechnical Engineering，2009，31(2)：161-165.(in Chinese))
[7]
李海涛，吴权，吕春峰.不同竖向荷载下PH管桩水平承载性能研究[J].工程勘察，2011，39(11)：19-23.(LI Haitao，WU Quan，LUChunfeng.Research on the lateral bearing capacity of prestressed high-strength concrete pipe pile under different vertical load[J].Geotechnical Investigation andSurveying，2011，39(11)：19-23.(in Chinese))
[8]
侯胜男，刘陕南，孙洋波，等.预应力管桩水平承载力现场试验与计算研究[J].土木建筑工程信息技术，2012，4(4)：28-31.(HOU Shengnan，LIU Shannan，SUN Yangbo，et al.Lateral capacity of PHC pile on site test and calculation research[J].Journal of Information Technology in Civil Engineering and Architectural，2012，4(4)：28-31.(in Chinese))
[9]
侯胜男，刘陕南，蔡忠祥，等.预应力管桩单桩水平承载力的试验判定标准探讨[J]. 岩土工程学报，2013，35(增1)：378-382.(HOU Shengnan，LIU Shannan，CAI Zhongxiang，etal. Test standards for lateral capacity of single PHC pile[J]. Chinese Journal of Geotechnical Engineering，2013，35(Supp.1)：378-382.(in Chinese))
[10]
方焘.阶梯型变截面桩变形计承载特性研究[博士学位论文][D].重庆：重庆大学，2012.(FANG Tao. Study on deformation and load-bearing characteristics of segmentally variable cross-section pile[Ph. D. Thesis][D].Chongqing：Chongqing University，2012.(in Chinese))
[11]
中华人民共和国行业标准编写组. JGJ94—2014建筑桩基技术规范[S]. 北京：中国标准出版社，2014.(The Professional Standards Compilation Group of People¢s Republic of China.JGJ94—2014Technical code for building pile foundations[S]. Beijing：China Standards Press，2014.(in Chinese))
2015, Vol. 34 
