多重失效机制下钢筋混凝土剪力墙可靠性分析  

Reliability analysis of reinforced concrete shear walls considering multiple failure mechanisms

作　　者：向东 高向玲[1,2] XIANG Dong;GAO Xiangling(College of Civil Engineering,Tongji University,Shanghai 200092,China;International Joint Research Center for Engineering Reliability and Stochastic Mechanics,Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学土木工程学院,上海200092 [2]同济大学工程可靠性与随机力学国际联合研究中心,上海200092

出　　处：《建筑结构学报》2024年第2期205-216,共12页Journal of Building Structures

基　　金：中德科学基金研究交流中心合作交流项目(M-0737);同济大学双带头人项目(0200219296)。

摘　　要：在静力推覆荷载作用下,材料非线性和随机性的耦合作用导致钢筋混凝土剪力墙出现不确定的失效模式,如弯曲失效或剪切失效,而采用构件弯曲失效的阈值难以准确度量剪切失效构件的可靠度。为此,采用基于运动学原理的剪力墙受剪计算方法对27个钢筋混凝土剪力墙的承载力以及8个钢筋混凝土剪力墙的水平荷载-位移曲线进行预测。考虑轴向荷载、结构尺寸及材料参数的不确定性,进行墙体在水平荷载作用下的随机非线性分析;通过定义构件的失效域并作为吸收边界条件,基于概率密度演化方法进行了多重失效模式下剪力墙的可靠度分析。结果表明:该方法能够较好地预测不同破坏模式下剪力墙的非线性响应,剪力墙多重失效的本质是内力重分布不同演化过程的结果;发生多重失效剪力墙的峰值点位移、残余点水平荷载的变异系数均可达到0.3以上。对某一特定的剪力墙考虑混凝土抗压强度、配筋率、配箍率以及高宽比等影响因素,发现提高混凝土强度可显著提高静力推覆荷载作用下钢筋混凝土剪力墙的可靠度。The coupling effect of material nonlinearity and randomness leads to the uncertainty of failure mode for reinforced concrete(RC)shear walls under the static pushover loads,i.e.,flexural failure and shear failure.However,it is difficult to accurately determine the reliability of shear failure components using the threshold value of flexural failure.Therefore,the calculation method of shear capacity of shear walls based on the kinematic theory is adopted to predict the shear capacity of 27 RC shear walls and the lateral load-displacement curves of eight RC shear walls.The uncertainties of axial load,dimensions and material properties are taken into account to conduct the stochastic nonlinear analysis of RC shear walls under lateral load.The reliability of RC shear walls considering multiple failure modes is analyzed based on the probability density evolution method by defining the failure domain and introducing the absorbing boundary condition.The results indicate that the proposed method can accurately predict the nonlinear response of shear walls with different failure modes,and the essence of multiple failures is the result of various evolution of internal force redistribution.The variation coefficients of displacement at peak value and the residual bearing capacity for shear walls with multiple failure modes reach 0.3 or above.Considering the influence factors of concrete compressive strength,longitudinal reinforcement ratio,stirrup ratio and aspect ratio for a specific shear wall,it is found that the reliability of RC shear walls under static pushover load is improved significantly by increasing the compressive strength of concrete.

关 键 词：钢筋混凝土剪力墙 多重失效机制 随机非线性分析 可靠度 

分 类 号：TU375[建筑科学—结构工程]