Numerical Simulation Of Dynamic Shear Failure Of Reinforced Concrete Beams

In order to avoid the catastrophic effect caused by shear failure of RC(reinforced concrete)structures,it is important to study the shear failure mechanism of RC members.During their service life,reinforced concrete structures may also be subjected to various types of dynamic loads.Due to the strain-rate effect of steel and concrete,the shear behaviors of reinforced concrete structures under dynamic loads behave quite differently as compared to the static load.At present,although the dynamic shear characteristics of reinforced concrete beams have been concerned by researchers,the current research is not systematic,especially lack of effect research of the loading rate,longitudinal reinforcement ratio,stirrup ratio and shear span ratio and other factors on the dynamic strength of the reinforced concrete beams,shear deformation and failure mode.This research mainly focuses the following four aspects:(1)The current research situations and obtained achievements in shear theory are described systematically.The main analysis model of shear resistance of RC beams are introduced in details,such as truss model,statistical analysis method,limit equilibrium theory,plasticity theory and nonlinear finite element theory.(2)The concrete damage plasticity model and the implicit solver and explicit solver commonly used in ABAQUS finite element software are summarized in details.A three-dimensional nonlinear finite model is carried out and the simulation results are verified with an experimental results to prove the feasibility of the simulation.(3)The RC beam FE model is established with the ABAQUS finite element software and the effects of the loading rate,shear span ratio and longitudinal reinforcement ratio on the mechanical properties,deformation and damage characteristics are systematically investigated.Further the parametric study is designed to investigate the influence of longitudinal reinforcement ratio,transverse reinforcement ratio and shear span ratio on dynamic increase factor(DIF)of ultimate resistance of RC beams under varying loading rates.(4)Based on the finite element software MSC.MARC and the user subroutine Uvscpl,the dynamic shear mechanical behaviors and deformation behaviors of reinforced concrete beams under different cyclic loading rates are simulated.Further the influences of shear span ratio,longitudinal reinforcement ratio and stirrup ratio on ultimate resistance of RC beams under varying cyclic loading rates are discussed.