基于车桥耦合振动的波形钢腹板箱梁体外预应力束疲劳损伤评估  

Fatigue Damage Assessment of External Prestressed Beam of Corrugated Steel Web Box Girder Based on Vehicle-bridge Coupling Vibration

作　　者：张甫 高华睿 杨渊 ZHANG Fu;GAO Hua-rui;YANG Yuan(The 4th Engineering Co.,Ltd.,of China Railway 12th Bureau Group,Xi'an 710000,China;Geotechnical and Structural Engineering Research Center of Shandong University,Jinan 250061,China)

机构地区：[1]中铁十二局集团第四工程有限公司,西安710000 [2]山东大学岩土与结构工程研究中心,济南250061

出　　处：《科学技术与工程》2023年第28期12250-12257,共8页Science Technology and Engineering

基　　金：山东省自然科学基金(ZR202102260046,ZR202102240664)。

摘　　要：波形钢腹板连续箱梁桥的动力特性研究相比其静力性能研究而言有所欠缺,尤其是车桥耦合振动下体外束疲劳损伤评估方面。基于ANSYS建立精细化波形钢腹板箱梁桥数值模型,开展体外束疲劳分析。利用MATLAB编制了考虑车辆类型,行车位置、速度、车头距及轴重等因素的随机车流程序。采用雨流计数法计算24 h内随机车流作用下体外束应力等效应力幅以及等效应力循环次数。修正Muller研究结果,提出应力比低于0.035且考虑侧向弯曲磨损作用下的钢绞线S-N(应力-寿命)公式。利用Miner累积损伤准则并考虑冲击系数的影响,推算波形钢腹板箱梁桥体外预应力束的疲劳损伤度及剩余疲劳使用寿命,同时分析了桥梁跨径对体外束疲劳损伤的影响。结果表明:移动荷载对不同位置处体外束应力影响线的大小顺序为:中跨跨中位置>边跨跨中位置>中跨1/4跨位置,中跨跨中位置处的体外束应力受到的车辆荷载的影响较大;随机车流对体外束产生的疲劳损伤随跨径增加而减小。Compared with the static performance of continuous box girder bridge with corrugated steel webs,the research on dynamic characteristics of continuous box girder bridge with corrugated steel webs is deficient,especially in the fatigue damage assessment of external tendons under vehicle-bridge coupling vibration.The ANSYS finite element software was used to establish a refined numerical model of corrugated steel web box girder bridges,and to perform external beam fatigue analysis.Using MATLAB,a random traffic flow program was prepared considering factors such as vehicle type,driving position,speed,head distance and axle load.The rain current counting method was used to calculate the equivalent stress amplitude of external beam stress and the number of equivalent stress cycles under the action of random vehicle flow within 24 h.Modified Muller's research results,put forward the S-N(Stress-Life)formula of steel strands with stress ratio lower than 0.035 and considering lateral bending wear.Using the Miner cumulative damage criterion and considering the impact of the impact coefficient,the fatigue damage degree and remaining fatigue life of the external prestressed beam of the corrugated steel web box girder bridge are calculated,and the effect of the bridge span on the external beam fatigue damage is also analyzed.The results show that the order of the effect of moving loads on the external beam stress at different positions is:mid-span mid-position>side span mid-position>mid-span 1/4 span position,and external beam stress at the mid-span position is greatly affected by vehicle loads.The fatigue damage of the external beam caused by random traffic flow decreases with the increase of the span.

关 键 词：波形钢腹板连续箱梁桥 随机车流 体外预应力束 疲劳 数值模拟 

分 类 号：U443.35[建筑科学—桥梁与隧道工程]