结合桥梁实际影响线信息的预应力识别方法  

Prestress identification method based on actual influence line information of bridge

作　　者：王宁波[1] 王灿 沈伟 黄天立[1] WANG Ning-bo;WANG Can;SHEN Wei;HUANG Tian-li(School of Civil Engineering,Central South University,Changsha 410075,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075

出　　处：《振动工程学报》2023年第3期688-697,共10页Journal of Vibration Engineering

基　　金：国家自然科学基金面上项目(52278233,52078486)。

摘　　要：预应力技术广泛应用于桥梁工程领域,对于在役桥梁结构,随着服役时间延长不可避免地存在预应力损失。准确识别桥梁预应力有助于了解其实际承载能力,保证桥梁长期安全稳定运营。本文研究预应力导致影响线的变化机理,建立预应力与桥梁影响线之间的对应关系(预应力梁影响线微分方程),并给出解析与数值求解方法,通过与仿真计算结果比较验证微分方程的正确性。研究预应力筋线形对挠度影响线(Deflection Influence Line,简写为DIL)的影响,在此基础上将影响线微分方程进行简化,提出结合实际影响线的预应力识别方法。开展预应力梁桥车‑桥耦合数值仿真试验,进行桥梁动力响应计算和影响线提取,验证本文结合桥梁实际影响线进行预应力识别方法的正确性与可行性。Prestressed concrete has been widely used in bridge engineering.In the service life of bridge structures,the prestress loss is inevitable.Therefore,an accurate identification of effective prestress is important to ensure the long-term safety and stable operation of bridge.The paper investigates change mechanism of influence line due to prestress and establishes the governing equation of the prestressed beam influence line.Both analytical and numerical solution are presented and verified by numerical simulation results.The influence of prestressing tendon line shape on the Deflection Influence Line(DIL)is further studied,the governing equation of the prestressed beam influence line is simplified.As such,a prestress identification method combined with the actual influence line is proposed.A numerical simulation test of the vehicle-prestressed beam bridge is carried out to calculate the dynamic response and extract the influence line of the bridge.The results are used to verify the correctness and feasibility of the proposed prestress identification method using the actual influence line of the bridge.

关 键 词：预应力识别 桥梁影响线 移动荷载 影响线微分方程 基函数 

分 类 号：U441[建筑科学—桥梁与隧道工程] U448.35[交通运输工程—道路与铁道工程]