Study On Seismic Performance Of Damaged Reinforced Concrete Cylinders With CGMM

Defects in design and construction,ship impact,seismic action or deterioration of performance caused by accumulated working time have resulted in the lack of sufficient seismic performance of piers,which will lead to the collapse and destruction of bridges and have a serious impact on social politics,economy and livelihood.Therefore,in order to maintain or even improve the seismic performance of damaged columns,the new reinforcement methods of cement-based grouting material and CGMM are used to study the effect of such reinforcement on the seismic performance of specimens.Main researches and conclusions:(1)Four specimens were fabricated for quasi-static test,and the test process,crack development,failure mode and deformation performance of the specimens were analyzed in detail.The hysteretic curve,skeleton curve and other seismic performance parameters are obtained through the test.Comparing the test results of the specimens,it can be concluded that the cracking load,peak load,cumulative energy dissipation and displacement ductility coefficient of the specimens strengthened with cement-based grouting material and CGMM are higher than those of the original reinforced concrete CP,and the seismic performance of the specimens strengthened with CGMM is improved.(2)Finite element analysis model is established by finite element software ABAQUS to simulate and analyze the specimens.The hysteresis curves and skeleton curves obtained by experiment and finite element simulation are compared and analyzed.In the model,the selection of the constitutive relationship of each material is determined to ensure the rationality of the model,and the simulated hysteresis curves and skeleton curves of each specimen are obtained.Comparing the simulation and test results of CP,CPR,CPRP1 and CPRP2,the results show that the calculation is in good agreement with the test results.The corresponding loads of each circle displacement are within the allowable range of error,and the corresponding peak loads of peak displacement are not very different.At the same time,the rationality of the model is guaranteed.(3)A reasonable finite element model is established by ABAQUS.On this basis,theseismic performance trend of the specimens is studied under different axial compression ratio,strength of cement-based grouting material,thickness of reinforcing layer,reinforcing height,diameter of wire mesh and number of layers of wire mesh.Then,a reasonable and effective restoring force model is established by regression analysis and fitting with MatLab and Origin software.