受拉钢筋混凝土构件破坏过程的数值模拟

采用三维材料破坏过程分析MFPA3D系统,对钢筋混凝土构件轴心受拉条件下的受力、变形与内部裂纹萌生、扩展及最终破坏全过程进行了数值试验研究。数值模型中引入统计分布函数反映了混凝土的非均匀性影响,并采用具有残余强度的弹性损伤本构模型及其破坏单元材料性质退化方法,利用位移加载方式对钢筋混凝土构件实施拉伸加载。通过对钢筋、素混凝土方形体以及钢筋混凝土方形柱体构件在拉伸作用下破坏过程的数值试验,分析了钢筋与混凝土两种材料之间的相互作用、约束机理和破坏机理。数值试验成果对于深入了解钢筋和混凝土的联合受力规律和钢筋在开裂前后对整体钢筋混凝土结构的作用机制有参考价值。

Numerical simulation of failure process of reinforced concrete specimen under uniaxial tension

By using MFPA3D,a modeling system of 3D Material Failure Process Analysis,reinforced concrete member under axial tensile has been analyzed for stress distribution,deformation and overall process of the initiation,propagation and final failure.The statistics functions that were utilized to the numerical models reflect the influence of the heterogeneous feature of the concrete.The analysis considers the constitutive model with residual strength after elastic damages and the failed elements are treated with reduced properties.The displacement-controlled loading scheme is used to fulfill the numerical simulation of failure process of the specimens.Through numerical modeling on the failure processes of reinforcement steel bars,plain concrete cubes and reinforced concrete prism specimens under tensile loading,the interaction,the confinement mechanism and the failure mechanism between the reinforcement steel and the concrete have been studied.The results of this numerical modeling improved our understanding to the stress distribution features of the reinforced concrete,as well as the functions of reinforcement steel to structures of the reinforced concrete before and after its fracture failure.