双向压弯下RC矩形空心截面桥墩承载能力评估  

Evaluation on Load Capacity Calculation of RC Rectangular Hollow Section Bridge Columns Subject to Axial Force and Biaxial Bending

作　　者：董振华[1] 韩强[1] 杜修力[1] 

机构地区：[1]北京工业大学城市与工程安全减灾省部共建教育部重点实验室,北京100124

出　　处：《中国公路学报》2014年第2期77-83,共7页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(50908005;51178008);NSFC-JST重大国际合作研究项目(51021140003);国家重点基础研究发展计划("九七三"计划)项目(2011CB013602)

摘　　要：为了评估双向弯曲作用下钢筋混凝土(RC)空心截面桥墩的安全性,根据双向弯曲共同作用下RC矩形空心截面中和轴的布置形式,推导了其轴力P和弯矩Mx及My的计算公式。结合数值模拟得到P-Mx-My三维相互作用屈服面,基于Bresler极限强度理论提出了轴压比小于0.3时,双向弯曲作用下RC矩形空心截面极限承载力的简化计算式。结果表明:应用P-Mx-My三维相互作用屈服面对试验墩的安全性校核结果与试验现象一致,且通过算例验证了提出的极限承载力简化计算式可准确校核双向水平荷载作用下矩形空心墩的安全性。In order to estimate the safety of the RC bridge columns with hollow section under biaxial bending, the calculation formulas for axial compression capacity and bending moment were proposed according to the distribution forms of neutral axis for rectangular RC hollow section under biaxial bending. The 3D interaction yield surface diagram of P-Mx-My was presented by numerical simulation. The simplified formula for ultimate bearing capacity calculation was obtained based on the Bresler ultimate strength theory for the RC bridge columns with rectangular hollow section with axial compression ratio less than 0.3 and under biaxial bending. The results show that the safety check result obtained by the 3D yield surface diagram is accordance with the observed experimental phenomena of tested RC bridge columns. The proposed formula is proved to be accurate to estimate the safety of rectangular hollow cross section under biaxial bending.

关 键 词：桥梁工程 空心截面桥墩 理论推导 极限承载力 双向压弯 三维相互作用屈服面 

分 类 号：U442.5[建筑科学—桥梁与隧道工程]