中南大学学报（自然科学版）2016，Vol.47Issue(11)：3784-3791,8.DOI:10.11817/j.issn.1672-7207.2016.11.023
桩体复合地基受压过程中侧向约束桩工程特性试验研究
Experimental study of mechanical characteristics of laterally constraint pile of pile composite foundation during loading
摘要
Abstract
Mechanical characteristics of laterally constraint pile of pile composite foundation during loading on pile composite foundation were studied by experiment. The results show as follows:during loading on pile composite foundation, soil pressure of pile side increases first and decreases later and shows peak along the depth. The peak value increases rapidly with the increase of loading, the position of the peak value is at 0.22H−0.33 H (H indicates pile length from the ground). Axial force P− depth z curves look like a tilted “S” shape, the upper part of the pile is subjected to tension and the lower part is under pressure, position of the tension peak value is at 0.15H, position of the pressure peak value is at 0.81H−0.92H. Frictional resistanceτ−depth z curves look like a tilted“C”shape as a whole, the upper part of the pile appears positive friction and the lower part appears negative friction, the neutral point is at 0.18H, position of the negative friction peak value is at 0.7H. Bending moment M increases first and decreases later and shows one or two peaks along the depth z, position of the upper peak value is at 0.37H, position of the lower peak value is at 0.59 H−0.70H. For the positive axial force (including peak value) and the variation range of the axial force zero burying depth and the negative friction peak value, side pile with small spacing is the biggest, side pile with large spacing is the second and middle pile is the least. Before the load reaches the inflection point of the composite foundation Q−s curve, middle pile has the largest bending moment, side pile with large spacing has the second and side pile with small spacing has the least. Beyond the inflection point load, side pile with large spacing has the largest bending moment, the middle pile has the second and side pile with small spacing has the least. The M−z curve of side pile with large spacing has one peak value, middle pile or side pile with small spacing has two peak values.关键词
桩体复合地基/加载/侧向约束桩Key words
pile composite foundation/loading/lateral constraint pile分类
交通工程引用本文复制引用
周德泉,颜超,刘宏利..桩体复合地基受压过程中侧向约束桩工程特性试验研究[J].中南大学学报（自然科学版）,2016,47(11):3784-3791,8.基金项目
国家自然科学基金资助项目(51378083，50978036)；湖南省交通运输厅资助项目(201304)；国家级大学生创新实验资助项目(201610536004)；长沙理工大学土木工程优势特色重点学科创新性资助项目(2016-1)(Projects(51378083,50978036) supported by the National Natural Science Foundation of China （51378083，50978036）
Project(201304) supported by the Department of Transportation of Hunan Province （201304）
Project(201610536004) supported by the National College Students Innovation Experiment （201610536004）
Project(2016-1) supported by the Key Innovative Advantage Subject of Civil Engineering in Changsha University of Science and Technology) （2016-1）
