Local Corroded Member Capacity Assessing Of Existing Reinforced Concrete

Based on the overview of former researches on capacity of existing reinforced concrete member,researchers have carried out many studies,but very few about capacity of local corrosion concrete structures.Practical engineering analysis showed that,as a result of local environmental impacts,many of the actual corrosion of reinforced concrete works are often local corrosion.Therefore,it is urgently carried out study of local corroded reinforced concrete structures carrying capacity assessing.In this paper,finite element software ANSYS was used for capacity research of local corroded reinforced concrete,which made local corroded member capacity assessing model of existing reinforced concrete.Main findings in this paper are included as follows:(1)Through non-linear finite element analysis,the calculation model of damaged bend concrete member is more close to realistic.The law of performance degradation was discussed on a variety of local corrosion of bend reinforced concrete members. The result show that:the geometric cross-section concrete compression is caused by the upper longitudinal reinforcement corrosion which made reinforced concrete beam stiffness decreased;the bond deterioration between steel and concrete is caused by corrosion which made reinforced concrete beam flexural capacity to further reduce. Base on finite element analysis results and using the ultimate equilibrium theory a calculation model for flexural strength of the cross-section local damage member is given in this paper.(2)Finite element analysis results show that:for eccentric compressive member, local corroded rate of force deterioration worse than longitudinal uniform corroded;in different corroded state,local corroded member ratio which bars with tension is to concrete tension strain is greater than uniform corroded;for large eccentric compressive member,the bigger rate of corrosion and longer corrosion length,the bigger stress steel bars is,under the same load.Base on finite element analysis results, the eccentric bearing capacity calculation model of different local corrosion state is given in this paper by using of finite element analysis results.(3)Finite element analysis results show that:for existing reinforced concrete beam, stirrup corrosion reduces bonding effect of reinforced concrete,which stirrup can't reach yield strength when concrete beam damaged and lead to the reduction of shear resistance;the more corrosion the less shear resistance when big height-to-span ratio. In this paper thinking over height-to-span ratio and corrosion rate,it is built respectively diagonal compression failure and shear-compression failure calculation model.