Mechanical Properties Research Of Non-uniform Corroded Reinforced Concrete Shear Wall Based On UMAT

The shear wall is widely used in high-rise buildings,and as the main anti-lateral force member of the high structure,the influence of force performance on the structure is especially important.Steel corrosion become the important factors that influenced the structure performance as the use of years increasing.The simulation analysis of the existing study almost from the uniform corrosion of steel bar,while non-uniform corrosion of steel bar in the actual project is more common,which the simulation research is relatively pinch.In this paper,we study the mechanical properties of the structural components of shear wall structures,and the main research contents and conclusions are as follows:(1)In this article we use ABAQUS user subprogram UMAT to write the subprogram that implements the rust-and-steel model,and verifies the validity of the program.By assigning different materials properties to different steel bars in the component,the distribution of the non-uniform corrosion of steel bars is realized.Using the force of the simple support beam,the differences in the stress performance of the uniform corrosion and non-uniform corrosion elements were analyzed.(2)By using the spring unit to consider the effect of the bond slip.As for the spring unit can't consider the damage change of components when unloaded.So we can just use spring element to consider the corroded reinforced beam stress under monotonic loading for summarizing the bond-slip of corroded reinforced concrete members the influence law of bearing capacity,and use penalty function method to the influence of bond-slip dispersion to damage evolution of concrete function,only to considering the damage evolution of the component under stress,the unloading damage does notcontinue to increase,and consider compressive damage recovery problem by the recovery coefficient.Then the performance of the reinforced concrete component under reciprocating load is approximated by the damage evolution function(3)From the comparative analysis of shear wall under different corrosion rate of mechanical properties,we can draw the conclusion when the shear wall corrosion rate is15%,the bearing capacity decreased to 84.63% of intact artifacts,which drops more obviously.It can be used as a canonical example to further study when the corrosion rate of 15%.(4)From the analysis of edge constraint component under different longitudinal reinforcement corrosion rate of shear wall mechanical properties,we can concluded that when the rate of corrosion attain 15%,it's 82.98% of the bearing capacity of shear wall undamaged,while drop more obviously.(5)when the corrosion rate was 15%,we can draw the conclusion from the different of Axial compression ratio of shear wall mechanical properties that with the increase of axial compression ratio,the bearing capacity of the shear wall increased,but the ductility performance was reduced,stiffness decrease rate faster.