复杂场地变电站基础中预应力管桩荷载传递规律的有限元分析  

Finite element analysis of load transfer law of prestressed pipe piles in substation foundation in complex site

作　　者：徐晓东 陈伟杰 朱佩宁 邱宇航 宋亚亚 翁佳 Xu Xiaodong;Chen Weijie;Zhu Peining;Qiu Yuhang;Song Yaya;Wong Jia(Chaozhou Power Supply Bureau of Guangdong Power Grid Co.,Ltd.,Chaozhou 521000,China;Guangdong Tianxin Electric Power Engineering Testing Co.,Ltd.,Guangzhou 510000,China)

机构地区：[1]广东电网有限责任公司潮州供电局,广东潮州521000 [2]广东天信电力工程检测有限公司,广东广州510000

出　　处：《能源与环保》2024年第6期206-211,共6页CHINA ENERGY AND ENVIRONMENTAL PROTECTION

基　　金：南方电网公司科技项目资助(035100KK52220024/GDKJXM20220843)。

摘　　要：在山区修建变电站等工程时,经常会遇到复杂场地基础的问题。倾斜软土地基是其中的一种特殊基础,具有独特的工程特性,给变电站的施工带来很大困难。为了研究复杂场地基础中预应力管桩的加固效果,指导预应力管桩设计。利用有限元软件建立了预应力管桩加固斜坡软土地基模型,研究了不同桩间距、桩长对路堤安全系数的影响,分析了预应力管桩的荷载传递规律、沉降以及路堤破坏机理。结果表明,在倾斜软土地基中设置预应力管桩,可以有效减少基础的变形,提高其稳定性;桩间距和桩长的改变对加固效果的影响显著,随着桩间距的减小和桩长的增加,倾斜软土地基变形逐渐减小,路堤安全系数逐渐增大;桩长应深入到嵌固层以下,过度减小桩间距后加固效果提高不大;路堤中部的桩基主要提供承载力,产生竖向位移较大,两侧的桩基主要提供抗滑力,产生横向位移较大;桩身轴力沿桩身先增大再减小,以软土层底面为分界线,上部桩身与下部桩身受剪应力相反,主要受力部位集中在桩端。在相关工程中,可根据需要合理设计预应力管桩的桩长、桩数和桩间距等参数,实现更加经济合理的加固方案。In the construction of substations and other projects in mountainous areas,the problem of complex site foundation is often encountered.The slope soft soil foundation is one of the special foundations.It has unique engineering characteristics and brings great difficulties to the construction of the substation.In order to study the reinforcement effect of prestressed pipe piles on the basis of complex sites and guide the design of prestressed pipe piles,the finite element software was used to establish the model of slope soft soil foundation reinforced by prestressed pipe pile,and the influence of different pile spacing and pile length on the safety factor of embankment was studied.The load transfer law,settlement of prestressed pipe pile and failure mechanism of embankment were analyzed.The results show that setting prestressed pipe piles in inclined soft soil foundation can effectively reduce the deformation of the foundation and improve its stability.The change of pile spacing and pile length has a significant effect on the reinforcement effect.With the decrease of pile spacing and the increase of pile length,the deformation of inclined soft soil foundation decreased gradually,and the safety factor of embankment increased gradually.The pile length should be deep below the embedded layer,and excessive reduction of pile spacing does not significantly improve the reinforcement effect.The pile foundation in the middle of the embankment mainly provides bearing capacity and produces large vertical displacement.The pile foundation on both sides mainly provides anti-sliding force and produces large lateral displacement.The axial force of the pile body increases first and then decreases along the pile body.Taking the bottom surface of the soft soil layer as the dividing line,the upper pile body is opposite to the lower pile body under shear stress,and the main stress part is concentrated at the pile end.In related projects,the parameters of pile length,pile number and pile spacing of pile-supported slope soft soil embank

关 键 词：预应力管桩 斜坡软土地基 强度折减法 荷载传递规律 有限元分析方法 

分 类 号：U416.1[交通运输工程—道路与铁道工程]