摘要
基于欧拉伯努利梁理论,提出非均布荷载、轴向力、梁端弯矩和非线性温度分布共同作用下的有滑移组合梁统一解析模型,推导组合梁挠度、界面剪力、滑移及截面应力的计算公式,开展简支组合梁和连续组合梁算例分析,讨论界面刚度和温度作用对界面滑移和挠度的影响.研究结果表明,组合梁温度作用产生的挠度与界面滑移由等效温度滑移应变和等效温度曲率决定,可以通过将桥面板与钢梁的温度分布各自分解为有效温度、竖向线性温差和残余温度等相互独立的3部分进行计算.简支梁和2跨连续梁算例在温度作用下的界面滑移沿梁长呈现反对称分布,滑移主要集中在距端部小于2 m的范围内,受滑移的影响,组合梁端部桥面板底面的拉应力水平较高,可以超过2 MPa,增加了底面混凝土开裂的风险.提出了温度作用下界面滑移组合梁的挠度影响系数,可以用于组合梁挠度的快速计算,其大小不仅与界面完全连接与界面无连接时组合梁的抗弯刚度比和组合效应系数有关,还受温度作用系数的直接影响.
A composite girder analytical model under the combined action of non-uniform distributed load,axial force,bending moment and nonlinear temperature load was proposed by considering interface slip based on Euler-Bernoulli beam theory.Analytical expressions of deflection,interface shear force,slip and sectional stress were deduced.Simply supported beam and continuous beam were taken as analysis examples.The influence of interface stiffness and temperature action on interfacial slip and deflection was discussed.Results showed that deflection caused by temperature action and interface slip of composite girders were determined by equivalent temperature slip strain and equivalent temperature curvature,which could be calculated by decomposing the temperature distribution of concrete deck and steel girder into three independent parts:uniform temperature,vertical linear temperature difference and residual temperature.The interface slips of simply supported beam and 2-span continuous beam under temperature action presented an anti-symmetric distribution along the beam length,and the slip was mainly concentrated in the range of less than 2 m of the end.The tensile stress level was high at the bottom surface of the concrete deck at the end of the composite girder due to the slip,which could exceed 2 MPa,increasing the cracking risk.The deflection influence coefficient under temperature action was proposed,which could be used for quick calculation of the temperature-caused deflection of composite girders.The deflection influence coefficient is not only related to the bending stiffness ratio of composite beams with complete shear connection and no interface connection and the combined effect coefficient, but also directly affected by the temperature effect coefficient.
作者
刘江
张宁
刘永健
马印平
LIU Jiang;ZHANG Ning;LIU Yongjian;MA Yinping(School of Highway,Chang’an University,Xi'an 710064,China;School of Water Resources and Architectural Engineering,Northwest A&F University,Yangling 712100,China;School of Civil Engineering,Chongqing University,Chongqing 400044,China)
出处
《浙江大学学报(工学版)》
EI
CAS
CSCD
北大核心
2024年第5期988-1000,共13页
Journal of Zhejiang University:Engineering Science
基金
国家自然科学基金资助项目(52108111)
中国博士后科学基金资助项目(2021M692747)
长安大学中央高校基本科研业务费专项资金资助项目(300102212102)。
关键词
钢-混组合梁
界面滑移
温度作用
等效温度滑移应变
等效温度曲率
挠度影响系数
steel-concrete composite girder
interface slip
temperature action
equivalent temperature slip strain
equivalent temperature curvature
deflection influence coefficient