某预应力混凝土简支T梁车撞受损分析及加固方案的研究  

Analysis of car crash damage analysis of a prestressed concrete simply supported T-beam and study of its reinforcement plan

作　　者：孙清祥 SUN Qingxiang(Changsha City Investment International Exhibition Center Investmentand Development Co.,Lud.,Changsha 410000,Hunan,China)

机构地区：[1]长沙城投国际会展中心投资开发有限责任公司,湖南长沙410000

出　　处：《工程建设》2022年第8期43-50,共8页Engineering Construction

摘　　要：为研究超高车辆与跨线桥梁体撞击后所需合理的加固或处理方案,本文以某预应力混凝土简支T梁为例,根据现场事故的检测报告及相关资料,建立受损前后的全桥模型进行分析,分别对承载能力极限状态和正常使用极限状态进行验算,并针对桥梁损坏程度提出不同的解决方案。结果表明:现状桥梁受损的三榀梁中,有两榀梁的损伤轻微,验算后均能满足规范要求,所以只需进行简单的混凝土修复即可;而受损最为严重的梁段正截面的压应力无法满足规范要求,需要进行加固处理,采用精细的非线性有限元,通过控制单元生死模拟桥梁结构的损伤、加固等受力阶段并行验算,发现采用修复混凝土及补强钢板后,受损区域的混凝土在活载作用下依旧容易开裂,该补强措施仍无法改善已有的损伤情况,难以消除应力重分布产生的较大压应力。本文可为同类事故的加固方案提供设计和分析思路。In order to study the reasonable reinforcement or treatment plan after the collision between vehicle and cross-line bridge, in this paper, a prestressed concrete simply supported T-beam is taken as an example.Based on the inspection report of the on-site accident and related data, a whole span bridge finite element(FE) model after damage is established.The bridge model is analyzed, and the ultimate state of the bearing capacity and the serviceability limit state are checked respectively.The results show that among the three beams of damaged bridge, two beams are slightly damaged, and they can meet the requirements of the specification after checking, simple concrete repair is needed.However, the compressive stress of the most severely damaged beam section cannot meet the requirements of the specification and needs to be strengthened.A nonlinear FE model is established, and the damage and reinforcement of the bridge structure are simulated through controlling birth and death of the element.The check calculation results show that after the repaired concrete and the reinforcing steel plate are used, the concrete in the damaged area is still prone to cracking under live load, and these two reinforcing measures cannot improve the existing damage and it is difficult to eliminate the large compressive stress caused by stress redistribution.The resultscan provide design and analysis ideas for the reinforcement of similar accidents.

关 键 词：梁格模型 非线性有限元 单元生死 损伤塑性模型 

分 类 号：U447[建筑科学—桥梁与隧道工程] TU375.1[交通运输工程—道路与铁道工程]