车辆荷载作用下钢-混凝土组合梁疲劳应力分析  

Fatigue Stress Analysis of Steel-Concrete Composite Beam Under Vehicle Load

作　　者：黄己伟[1] 刘丹[1] HUANG Jiwei;LIU Dan(Sichuan College of Architectural Technology,Deyang 618000,China)

机构地区：[1]四川建筑职业技术学院,四川德阳618000

出　　处：《河南科技》2024年第9期78-82,共5页Henan Science and Technology

基　　金：四川建筑职业技术学院院级课题项目(2022KJ09);四川建筑职业技术学院院级课题项目(2020KJ05);四川建筑职业技术学院“四技服务”项目“恶劣环境下耐候钢拱桥桥面系叠合梁疲劳性能研究”。

摘　　要：【目的】随着桥梁服役期延长和车辆荷载增加等多种因素的影响,结构承载力会变得越来越弱,疲劳寿命不断降低,最终可能导致低应力疲劳破坏。因此有必要对车辆荷载下拱桥钢混组合梁的疲劳细节应力进行研究。【方法】采用数值模拟的方法,利用Midas FEA NX软件建立3个标准长度的三维实体精细有限元模型,分析钢混组合梁易损疲劳关键点的位置,并研究车辆荷载横向最不利加载位置和纵向加载下的疲劳细节应力变化规律。【结果】结果表明,组合梁次横梁与中纵梁交点处有三处疲劳关键点;靠近桥梁中线位置是车辆荷载下钢梁疲劳最不利的横向加载位置;四种不同标准的纵向车辆加载时,三个疲劳关键点均出现两次应力峰值,且最大应力幅值均低于常幅疲劳强度的极限值。【结论】研究成果可为钢-混凝土组合梁试验和相关研究提供参考。[Purposes]With the extension of bridge service life and the increase of vehicle load,the bear⁃ing capacity of the structure will become weaker and weaker,and the fatigue life will continue to de⁃crease,which may eventually lead to low stress fatigue failure.Therefore,it is necessary to study the fa⁃tigue detail stress of steel-concrete composite beam of arch bridge under vehicle load.[Methods]A three-dimensional solid finite element model of three standard lengths was established by using Midas FEA NX software through numerical simulation method.The location of the key points of vulnerable fa⁃tigue of steel-concrete composite beams was analyzed,and the variation law of fatigue detail stress under the most unfavorable lateral loading position and longitudinal loading of vehicle load was studied.[Find⁃ings]The results show that there are three fatigue key points at the intersection of the upper transverse beam and the middle longitudinal beam of the composite beam.The position near the midline of the bridge is the most unfavorable transverse loading position for the fatigue of the steel beam under vehicle load.When four different standards of longitudinal vehicle are loaded,there are two stress peaks at three fatigue key points,and the maximum stress amplitude is lower than the limit value of constant amplitude fatigue strength.[Conclusions]The analysis results can provide reference for the test and related re⁃search of steel-concrete composite beams.

关 键 词：拱桥 钢-混凝土组合梁 疲劳应力 S—N曲线 车辆荷载 

分 类 号：U448.36[建筑科学—桥梁与隧道工程]