Numerical Simulation Study On The Dynamic Mechanical Behaviors Of Reinforced Concrete Shear Walls

The reinforced concrete(RC)shear wall is one of key components in many buildings.During the period of their serves,shear walls may endure all kinds of dynamic loading.Due to the strain-rate sensitivity of the steel and concrete materials,the dynamic mechanical properties of the RC shear wall should be different from those at the static loading conditions,which may lead to the shear failure although it is designed according to bending failure by the code.Therefore,it is necessary to study the dynamic shear characteristics of RC shear walls.Although the behavior of shear wall is studied abundantly,the research of the dynamic shear failure of the shear wall is lack.In order to intensively study the mechanical behaviors of the dynamic shear failure of the shear wall,the rate-dependent concrete damage plastic model and the Cowper-Symonds model of steel in ABAQUS are used to analyze the dynamic behavior of RC shear walls with different loading rates.The following research work and result will be carried out in the paper:(1)The research methods of RC shear walls in experimental research,numerical calculation and shear theory analysis are reviewed.The advantages and disadvantages of the three research methods are contrasted.The research method is selected as numerical calculation.(2)The damage-plasticity model of concrete and rate-dependent plasticity model of steel,the nonlinear dynamic analysis method in ABAQUS are introduced.The feasibility and accuracy of the model and method are demonstrated by numerical simulation of a typical RC shear wall.The results show that the load-displacement curves of the numerical simulation fit for the experimental data.The distribution of the cloud is in accordance with the typical shear failure characteristics.It is feasible to use the above models and methods for numerical simulation.(3)The monotonic loading of RC shear walls designed according to the code are simulated in ABAQUS.Based on the results,such as loading-displacement curves and clouds,the effects of loading rate,shear span ratio,horizontally and longitudinal reinforcement ratio on the ultimate load,peak displacement,energy dissipation capacity,displacement ductility and failure modes of shear walls are studied.The results show that the ultimate load,ductility and energy dissipation capacity of RC shear walls are improved with the increasing of loading rate and horizontally reinforcement ratio,the transition of RC shear walls from shear failure to flexural failure is promoted.Following the increasing of longitudinal reinforcement ratio,the ultimate load,ductility and energy dissipation capacity are reduced.With the increasing of shear span ratio,the ultimate load is obviously reduced,and the ductility and energy dissipation capacity are obviously improved.(4)The reversed cyclic loading of RC shear walls are simulated.Based on the results obtained,the effects of loading rate,shear span ratio,horizontally and longitudinal reinforcement ratio on the ultimate load,peak displacement,hysteretic energy,displacement ductility,stiffness degradation,skeleton curve and failure modes of RC shear walls are studied.The results show that the results of monotonic loading are different from reversed cyclic loading,due to the neglect of the bond slip.The ultimate load of reversed cyclic loading is reduced by 10%~20% compared with monotonic loading,the displacement is obviously reduced,and the decreasing of strength is faster.The effects of loading rate,shear span ratio,and reinforcement ratio are similar to monotonic loading.