柔性基础下碎石桩复合地基桩土应力比及沉降计算  

Pile-soil stress ratio and settlement of composite ground with gravel piles in flexible foundation

作　　者：赵明华[1] 牛浩懿 刘猛[1] 谭鑫 

机构地区：[1]湖南大学岩土工程研究所,湖南长沙410082

出　　处：《岩土工程学报》2017年第9期1549-1556,共8页Chinese Journal of Geotechnical Engineering

基　　金：国家自然科学基金项目(51478178);国家青年自然科学基金项目(51508181)

摘　　要：深入研究柔性基础下碎石桩复合地基受力变形机理,考虑到碎石桩复合地基桩体侧向鼓胀及桩体的整体性,在径向位移模式分析中引入横截面剪应力的影响,并由此建立了碎石桩鼓胀段荷载传递模式。然后,结合桩身荷载传递规律,导出了柔性基础下碎石桩鼓胀变形的控制微分方程,获得了柔性基础下碎石桩复合地基桩土应力比及沉降。最后通过实例和数值模拟分析,表明该方法具有较好的合理性与可行性,参数分析表明,增大桩土模量比和减少置换率会提高桩土应力比,荷载水平则会影响径向鼓胀变形的程度。The deformation mechanism of composite ground with gravel piles in flexible foundation is thoroughly studied, and the effect of a cross-sectional shear stress is introduced in the analysis of radial displacement mode considering the lateral bulging and integrity of the piles. Therefore, a bulging load transfer mode of gravel piles is established. Then, a differential equation for the bulging deformation of gravel piles in flexible foundation is derived based on the load transfer law. The pile-soil stress ratio and settlement flexible foundation are obtained. Finally, the proposed method is proved to be of certain rationality and feasibility through case studies and numerical simulations, and the parameter analysis indicates that increasing pile-soil modulus ratio and reducing the replacement rate will increase the pile-soil stress ratio, while the load level will affect the radial bulging deformation degree.

关 键 词：碎石桩 复合地基 径向位移 荷载传递 桩土应力比 沉降 

分 类 号：TU43[建筑科学—岩土工程]