弯曲破坏冻融损伤RC框架梁柱数值模型  

Numerical Model of Frost-damaged RC Frame Beam-column Under Flexural Failure

作　　者：李莉斯[1] 索朗白姆[1] 郑山锁[2] 王胜利 LI Lisi;SUOLANG Baimu;ZHENG Shansuo;WANG Shengli(School of Engineering,Tibet university,Lasa 850000,China;School of Civil Engineering,Xi'an University of Architecture and Technology,Xi'an 710055,China;China Energy Engineering Group Shaanxi Electric Power Design Institute Co.,Ltd.,Xi'an 710054,China)

机构地区：[1]西藏大学工学院,西藏拉萨850000 [2]西安建筑科技大学土木工程学院,陕西西安710055 [3]中国能源建设集团陕西省电力设计有限公司,陕西西安710054

出　　处：《应用基础与工程科学学报》2023年第4期906-920,共15页Journal of Basic Science and Engineering

基　　金：国家自然科学基金项目(52068064);西藏自治区自然科学基金项目(XZ 2019ZR G-21)。

摘　　要：为探究弯曲破坏型冻融损伤钢筋混凝土(RC)框架梁柱抗震能力进而对其展开准确评估,通过对国内外已有冻融损伤RC梁柱拟静力试验数据的对比分析与归纳总结,深入系统地探究了冻融循环次数NFTCs、混凝土强度f_(cu)、轴压比n对RC梁柱抗震能力的影响.采用理论知识构建了未冻融RC框架梁柱弯矩-转角(M-θ)恢复力模型骨架曲线计算方法,进而提出了可考虑冻融损伤参数F(F综合了NFTCs和f_(c)的影响)和轴压比n影响的冻融损伤RC框架梁柱M-θ恢复力模型骨架曲线计算公式.在此基础上,基于能量耗散原理,引入循环退化指数βi用以表征梁柱构件的强度退化与刚度衰减,构建了适用于弯曲破坏冻融损伤RC梁柱的M-θ恢复力模型.将所建立的M-θ恢复力模型代入到OpenSEES的零长度单元ZeroLength Element中,利用集中塑性铰模型建立了适用于弯曲破坏型冻融损伤RC梁柱数值模型.通过模拟值与试验值的对比表明,构建的数值模型能较为准确地标定低周往复下弯曲破坏冻融损伤RC框架梁柱的滞回性能,可用于RC框架结构的抗震能力评估.In order to deeply explore the seismic capacity of the frost-damagedreinforced concrete(RC)frame beam-column subjected to flexural failure and then carry out an accurate evaluation.Based on the comparative analysis and summary of the existing quasi-static test data of frost-damaged RC beam and column at home and abroad,the influence of the number of freeze-thaw cycles NFTCs,concrete strength f_(cu) and axial force ratio n on the seismic capacity of RC beam-column is systematically explored.The calculation method of skeleton curve of moment-rotation(M-θ)hysteretic model of unfrozen RC frame beam-column under flexural failure is constructed theoretically.Moreover,a formula for calculating the M-θskeleton curve of frozen-thawed damage RC frame beam-column under flexural failure is proposed considering the influence of freeze thaw damage parameters F(F combines the effects of NFTCs and f_(c))and axial force ratio n.On this basis,based on the principle of energy dissipation,the cyclic degradation indexβi is introduced to characterize the strength degradation and stiffness degradation of beam-column members,and the M-θrestoring force model suitable for frost-damaged RC beam-column subjected to flexural failure is established.The M-θhysteretic model of frost-damaged RC beam-column is substituted into the ZeroLength Element of OpenSEES,and the numerical model of frozen-thawed damage RC beam-column subjected to flexural failure is established by using the lumped plastic hinge model.The comparison results between the experimental and simulated indicate that the numerical model can accurately calibrate the hysteretic behavior of frost-damaged RC frame beam and column under low cyclic reciprocating loading,and can be used to evaluate the seismic capacity of RC frame structures.

关 键 词：冻融损伤 RC框架梁柱 弯曲破坏 集中塑性铰模型 弯矩-转角恢复力模型 抗震性能 OPENSEES 

分 类 号：TU375.4[建筑科学—结构工程]