Numerical Analysis Of Earthquake Resistance Of Brick Masonry Strengthened With Pasted Steel And Polymer Mortar

Masonry structure is widely used in industrial and civil construction in China because of its low cost,wide material source,good durability,good fire resistance and convenient construction.However,the masonry structure is self-contained and has poor seismic performance,which causes serious damage during the earthquake.Reinforcement is currently the main means to improve the performance of existing masonry structures.Domestic and foreign scholars have done a lot of experimental research.With the development of computer and finite element theory,the establishment of masonry numerical model to study its reinforcement performance is more efficient and convenient,and has important guiding significance for practical engineering.In this paper,based on the method of reinforcing steel-polymer mortar surface layer masonry,the reinforcement performance is systematically studied.In the research process,the masonry modeling strategy was first studied,and the appropriate mechanical assumptions were made for the masonry mate rials and the reinforcement materials.The constitutive relations and parameters of the masonry and the reinforcement materials were given.Secondly,based on the ABAQUS/CAE module,the numerical model of unreinforced masonry and reinforced masonry is established.The multi-parameter comparison verification is carried out based on the existing experimental results.The simulation errors of each index are quantitatively analyzed,and the reinforcement described in this paper is demonstrated.Feasibility of masonry modeling methods.Finally,the variable parameters analysis of the reinforced masonry model is carried out within the working conditions permitted by the current regulations.The seismic behavior index of the reinforced masonry is affected by various factors,and the best reinforcement scheme is given.Perform a horizontal comparison analysis.Based on the test results and simulation results,the standard formula for the shear capacity of low-strength brick masonry walls is appropriately modified,and the influence of the aspect ratio is considered.Combined with the calculation formula of shear capacity of steel mesh cement mortar surface layer reinforcement method in the current masonry reinforcement specification,the calculation formula of shear capacity of bonded steel-polymer mortar surface layer masonry reinforcement method is given.The numerical results show that the numerical model constructed in this paper has a good simulation effect on the cracking displacement,ultimate load,ultimate displacement,ductility coefficient,stiffness and energy consumption index of the wall.According to the comprehensive statistics,the guarantee value of the absolute value of the error within 20% is 81%.In addition,this paper analyzes the reinforcement effect and applicable conditions of the bonded steel-polymer mortar surface layer to strengthen the masonry,and gives specific reinforcement suggestions.The modified formula of the shear strength of the unreinforced masonry given in this paper is better for the low strength grade brick masonry.The correction formula for the shear capacity of masonry reinforced with cement-polymer mortar surface layer proposed in this paper is good,which can provide technical reference for the engineering application and p romotion of the reinforcement method.