摘要
为研究堆载对桥梁被动桩的影响,以某桥为背景,采用有限差分法进行被动桩偏移受力分析,判断基桩能否继续使用并提出处理措施。采用有限差分法建立下部结构模型,计算堆载作用下桥墩偏移并与实测值对比,分析基桩内力及偏移,按圆形截面钢筋混凝土偏心受压构件计算最大裂缝宽度并评估基桩状态,根据评估结果提出处理措施。结果表明:堆载导致桥墩偏移,墩顶横向偏移计算值与实测值比较吻合;堆载作用下,基桩产生了较大偏移和弯矩,桩顶轴力和桩身轴力分布不均,并产生不同程度的负摩阻力(距堆载越近负摩阻力越大);最大裂缝宽度为0.08mm,小于规范限值,判断基桩可以继续使用,提出堆载反压和应力释放孔联合纠偏,开挖卸载、水平顶推结合应力释放孔纠偏等处理措施。
To study the influences of stacked load on the bridge passive piles,a bridge was taken as the research object,the force analysis of offsetting of the passive piles was conducted by the finite difference method,the piles were judged if they could be continuously used and the corresponding handling measures were proposed.The models for the substructure of the bridge were set up also by the finite difference method,the offsetting of the piers of the bridge under the action of the stacked load was calculated and the calculated values were compared to the measured ones.The internal forces and offsetting of the piles were analyzed.In terms of the circular reinforced concrete eccentric compression components,the maximum crack width of the piles was calculated,the force conditions of the piles were assessed and based on the assessment,the handling measures were proposed.The results show that the stacked load causes the offsetting of the piers and the calculated and measured values of the lateral offsetting of the pier tops are accordant.Under the action of the stacked load,the great offsetting and bending moment occur in the piles,the axial force distribution in the pile tops and pile shafts is not uniform and the negative frictional resistance of different degrees occurs （the closer to the stacked load,the greater the negative frictional resistance will be）.The maximum crack width of the piles is 0.08 mm and is less than the specified values in the codes.It is therefore judged that the piles can be continuously used and the handling measures of rectifying the offsetting of the piles,using the combined method of reverse compression of the stacked load and stress release holes and the measures of excavating,unloading,horizontal pushing aided by the utilization of the stress release holes are also proposed.
出处
《桥梁建设》
EI
CSCD
北大核心
2014年第4期22-26,共5页
Bridge Construction
关键词
桥梁基础
被动桩
堆载
位移
轴力
负摩阻力
裂缝宽度
纠偏
有限差分法
bridge foundation
passive pile
stacked load
offsetting
axial force
negative frictional resistance
crack width
offsetting rectifying
finite difference method
作者简介
马远刚 1976-,男,教授级高工 1997年毕业于武汉水利电力大学水利工程专业,工学学士,2000年毕业于武汉水利电力大学岩土工程专业,工学硕士,2011年毕业于中国科学院武汉岩土力学研究所岩土工程专业,工学博士.研究方向：岩土工程科研检测 E-mail：brsi2004@126.com
王艳芬 1972-,女,高级工程师 1996年毕业于华中理工大学建筑工程专业,工学学士,2002年毕业于华中科技大学结构工程专业,工学硕士,2007年毕业于华中科技大学结构工程专业,工学博士.研究方向：岩土工程数值分析 E-mail：yinying20015@163.com
陈晨 1984-,男,博士生 2007年毕业于湖北工业大学桥梁工程专业,工学学士,2012年毕业于武汉理工大学岩土工程专业,工学硕士.研究方向：岩土工程地面与地下工程 E-mail：clarencechen@yeah.net
