曲线变宽桥梁爬移成因分析及处治对策  

Cause Analysis and Treatment Of Bridge Creep With Curve Widening

作　　者：李伟 

机构地区：[1]广东和立土木工程有限公司

出　　处：《交通与港航》2024年第6期90-94,共5页Communication & Shipping

摘　　要：广东省某高速公路匝道桥出现整体爬坡,导致支座严重损坏,固定支座垫石开裂,单向滑动支座纵向限位钢板断裂;通过对整体温度、梯度温度、收缩、徐变、汽车制动力、离心力等因素进行分析,得出桥梁产生整体爬移及支座相关病害的主要原因为:在温度力的反复作用下,桥梁沿纵向和径向均出现不同程度的膨胀收缩现象,纵桥向出现整体爬坡现象,同时由于曲线变宽桥梁结构特性及支座约束边界的影响,使得桥梁实际位移方向与支座允许滑动方向不一致,导致支座限位钢板受到较大的交变应力荷载,最终造成支座钢板断裂破坏。通过采取更换支座形式,使新旧支座共同承担水平力,验算表明更换支座形式可有效防止既有桥梁爬移,处治对策有效。An expressway ramp bridge in Guangdong province appears integral climbing,resulting in serious damage to the support,cracking of the fixed support cushion stone,and fracture of the longitudinal limit plate of the one-way sliding support.Through the analysis of the overall temperature,gradient temperature,shrinkage,creep,automotive braking force,centrifugal force and other factors,it is concluded that the main causes of the bridge’s overall climbing and bearing related diseases are as follows:Under the repeated action of temperature forces,the bridge expands and contracts in different degrees along the longitudinal and radial directions,and the overall slope climbs along the longitudinal direction.At the same time,due to the influence of the structural characteristics of the bridge with a wider curve and the constrained boundary of the support,the actual displacement direction of the bridge is inconsistent with the allowable sliding direction of the support,resulting in greater alternating stress loads on the limiting steel plate of the support.Finally,it causes the fracture of the support steel plate;By replacing the support form,the new and old supports jointly bear the horizontal force.The checking calculation shows that the replacement of the support form can effectively prevent the existing bridge from climbing,and the treatment measures are effective.

关 键 词：曲线变宽桥梁 整体爬移 支座相关病害 处治对策 

分 类 号：U445.7[建筑科学—桥梁与隧道工程]