旧桥承载力的分析及鉴定

Analysis and Verification of Load Bearing Capacity of Old Bridge

研究目的:鉴定旧桥承载力,可以评估桥梁运营的安全性,为加固设计提供依据。本文以钢筋混凝土简支T形梁桥为例,从桥梁整体工作状况、钢筋锈蚀程度、梁体开裂程度等因素入手,通过数值分析,对旧桥的承载力进行分析和鉴定。总结出旧桥承载力鉴定的基本程序。研究结论:旧桥承载力的鉴定,应该按照全桥检查、细部检测、主梁承载力检算、全桥承载力鉴定的程序进行。即首先根据桥梁的整体工作状况及病害情况确定折减系数,然后对病害最为严重和负荷最大的两类主梁进行检算,最后根据检算结果对桥梁承载力进行鉴定。对文中所列桥梁的承载力进行鉴定可见:该桥设计荷载低,加之病害的影响,承载力不能满足荷载的要求。必须对桥梁进行提高承载力加固,以保证桥梁运营的安全。

Research purposes：By verification of the load bearing capacity of the old bridge,the operation security of bridge can be appraised and the basis can be offered to the reinforcement design of the bridge.In this paper,taking a reinforced concrete simply-supported T-beam bridge as an example,the analysis and verification are made for the loading bearing capacity of the old bridge by a numerical analysis from the aspects of the overall working situation of the bridge,the corrosion degree of the steel bar and the cracking degree of beam,and the basic procedure of verifying the load bearing capacity of old bridge is offered. Research conclusions：When verifying the load bearing capacity of old bridge,the procedures of overall inspection,detailed detection,calculation of load bearing capacity of the beam and the verification of the load bearing capacity of the bridge should be followed.It means that,firstly,the reduction coefficient is defined according to the overall working situation and the defect situation of the bridge,then the load bearing capacity of the beams with most serious defects or bearing maximum load is calculated,and finally,the load bearing capacity of the bridge is verified according to calculation result.The verification of the load bearing capacity of the bridge presented in this paper shows as the design load of this bridge is low and the bridge has some defects,the load bearing capacity of the bridge can＇t satisfy request.So the bridge must be reinforced to enhance its load bearing capacity for ensuring the operation security of the bridge.