Numerical And Theoretical Study Of High-Strength Steel Stranded Wire Meshes Reinforced ECC Under Tensile And Bending Load

Combined the advantages of Engineering Cementitious Composites(ECC)with multiple micro-cracking development pattern and tensile strain-hardening characteristics,and high tensile strength and good corrosion resistance of high-strength steel strands,the research group innovatively proposed a novel type of high-performance composite materials-high-strength stainless steel wire mesh reinforced ECC.In this paper,based on the previous experimental research,the theoretical analysis and numerical simulation on the tensile and flexural properties-of high-strength stainless steel wire mesh reinforced ECC are further conducted.The main research contents and conclusions are as follows:(1)The software DIANA is used to establish the finite element(FE)model,and the accuracy and validity of the high-strength stainless steel wire mesh reinforced ECC tension model are verified by comparing the FE model results with the test results.According to the test and finite element simulation results,the expression of the descending stage of the tensile constitutive relation of the high-strength stainless steel wire mesh reinforced ECC is proposed.By further changing the reinforcement ratios anddiameters of the steel strand,ECC strength and other parameters etc al,the accuracy of the full curve expression of the high-strength stainless steel wire mesh reinforced ECC tensile constitutive model is verified.(2)On the basis of the ECC tensile the "ideal rigid-plastic" model,it is recommended to improve the parameter values of the ECC tensile "ideal rigid-plastic" model based on the bending test results of the high-strength stainless steel wire mesh reinforced ECC plate.The simplified calculation formula of the flexural bearing capacity of the high-strength stainless steel wire mesh reinforced ECC plate is proposed.Meanwhile,the theoretical calculation formulas of the maximum reinforcement ratio and the minimum reinforcement ratio are proposed,and the applicable scope of the simplified theoretical formula of bearing capacity is clarified.(3)ABAQUS finite element software is used to establish the bending model of high-strength stainless steel wire mesh reinforced ECC plate,and the accuracy of the model is verified based on the previous test results of the research group.The effects of longitudinal steel wire strands reinforcement ratio,section geometry parameters and ECC material parameters on the performance of the high-strength stainless steel wire mesh reinforced ECC plate are analyzed.The results show that by increasing the reinforcement ratio,section height,ECC cracking strength and ultimate tensile strength of longitudinal steel strands,the flexural rigidity and bearing capacity of the plate are obviously improved,and the ductility is decreased;By improving the compressive strength of ECC,the bearing capacity,stiffness and ductility of the plate have been significantly improved;The finite element analysis of full-scale high-strength stainless steel wire mesh reinforced ECC plate is carried out.The longitudinal steel strand reinforcement ratio and plate section height had significant effects on the stiffness,bearing capacity and ductility of the full-scale plate,and the influence rule is the same as the above results.(4)The comparative analysis of the results of the simplified bearing capacity calculation formula of the high-strength stainless steel wire mesh reinforced ECC plate under bending with the test results and the finite element analysis results shows that the formula for calculating the bearing capacity of flexural members proposed in this paper has high accuracy and wide applicability.