Study On Seismic Performance Of Steel Reinforced Recycled Concrete Column

With the acceleration of China's urbanization construction,on the one hand,reinforced concrete is used in building construction and road construction,which leads to shortage of natural resources.On the other hand,it is the aging demolition of the old buildings,which produces a lot of waste concrete,and the environmental pollution caused by improper handling.Therefore,more attention paid to the development and application of recycled concrete,but due to the mechanical properties of recycled concrete,compared with ordinary concrete,the deformation capacity of poor shortcomings limit the application of recycled concrete in practical engineering.The reinforced concrete composite structure overcomes the shortcomings of the recycled concrete structure and extends the application range of recycled concrete.At present,there are relatively few researches on the structure of reinforced concrete structures in China.In this paper,a model of two steel reinforced concrete columns is established through ABAQUS finite element software,and the seismic performance analysis is carried out.Found that the results of simulation results with test hysteretic curve and skeleton curve,there are some differences,but the error of the simulation value and experimental value in the range of allowed,in general,the finite element simulation seismic effective steel recycled concrete columns,the simulation results can be used for data analysis.In this paper,the seismic performance of 14 steel reinforced concrete column specimens subjected to low cyclic loading is analyzed.Steel recycled concrete column specimens in the process of simulation,by changing the replace rate of recycled aggregates,specimen shear span ratio,axial compression ratio,stirrup ratio of volume,recycled concrete strength grade and steel strength six parameters,explore the hysteretic characteristics of steel recycled concrete columns and skeleton curve,stiffness degradation,ductility,intensity attenuation performance and the influence of mechanics performance on energy consumption.Simulation results show that recycled aggregate rate has little influence on seismic performance of steel recycled concrete columns,with the increase of replacement ratio,the reduction in seismic performance slightly,instead of the rate of 100%compared with the replace rate of 0,maximum horizontal bearing capacity decreased by 10%;Shear span ratio,axial compression ratio,stirrup ratio and volume of recycled concrete strength grade,the seismic performance of steel recycled concrete columns are of great influence,with the increase of the shear span ratio,the more full hysteretic curve,ductility of the specimens,the shear span ratio of 3.25,compared with the shear span ratio of 1.46 ductility increased by 30%,good seismic performance;Weakened with the increase of axial compression ratio,energy dissipation capacity,and the intensity attenuation speed,axial compression ratio of 0.8 and axial compression ratio of 0.4,compared to the cycle number seven times less,so the smaller axial compression ratio can increase the steel recycled concrete column's ability to fight earthquake;With the increase of volume stirrup ratio,can strengthen reinforced the restriction in recycled concrete,displacement ductility,energy dissipation ability stronger,stirrup ratio and stirrup ratio of 1.09%with 1.97%compared to the limit capacity increased by 20%,effectively improve the seismic resistance of steel recycled concrete columns;With the ascension of recycled concrete strength grade,level limit carrying capacity increased,the stiffness of pillars,brittleness increases,the strength grade of 60 mp compared with 40 mp,10%lower ductility,energy dissipation ability is abate,seismic performance of steel recycled concrete columns;With the increase of strength of steel,steel recycled concrete column horizontal bearing capacity increases,but the displacement ductility decreases,and Q235 grade specimens compared with specimen Q390 level,20%lower ductility and seismic performance.To sum up,the shear span ratio and axial compression ratio on the seismic performance of steel recycled concrete column is larger,in order to meet the requirements of steel recycled concrete columns of earthquake,the shear span ratio should be greater than 2,axial compression ratio should be less than 0.6,recycled concrete strength and the strength of steel on the premise of guarantee the bearing capacity requirement,choose low strength grade of material is more advantageous to enhance the seismic performance of steel recycled concrete column.Based on steel recycled concrete column simulation based on the analysis of the seismic performance,and established the four linear restoring force model of steel recycled concrete column,steel recycled concrete columns and deduces the restoring force model of skeleton curve and the calculation method of feature points is proposed according to the stiffness degradation rule of steel recycled concrete columns,steel recycled concrete columns for research provides reference elastoplastic dynamic response.