view:27620 Last Update: 2020-2-29
داوود نادري ، جواد مرادلو
تحليل غيرخطي ديناميکي ديوارهاي بتني مسلح با ديدگاه مکانيک آسيب
Nonlinear dynamic analysis of concrete shear walls using damage mechanics approach
In many case of engineering problems, for precise analysis, impact of nonlinear behavior of materials must be regarded. In this study, attention is focused on the nonlinear dynamic analysis of reinforced concrete shear walls. Reinforced concrete shear walls are commonly used in structures in seismic areas to resist laterally applied earthquake loads. A new crack model based on damage mechanics approach is presented. The proposed model considers the nonlinearity of concrete and reinforcement. The concrete model is based on damage mechanic model in concept of rotational cracking theory. Reinforcement is modeled by a bilinear relationship with Smeared model. In Smeared model assumed that the reinforcement bars are distributed in concrete element and form reinforced concrete element. In analysis a 4-node rectangular isoparametric plane stress element is used in finite element discritization. The Newmark method to solve the dynamic equation and the modified Newton-Raphson method to linearization of nonlinear equations is employed. Based on mentioned algorithms a new FEM code is developed. Validity of the proposed model and numerical algorithms has been checked using the available experimental results. Nonlinear dynamic analysis of some concrete shear wall is carried out. The comparison shows that this approach has good accuracy. Keywords: Reinforced concrete, Finite element method, Smeared model, Damage mechanics, nonlinear dynamic analysis .