Research On Seismic Behavior Of Rural Masonry Reinforced With Pp-bands

As an emerging reinforcement technology of masonry structure,the pp-bands reinforcement technology has a vast prospect and development space.Compared with traditional strengthening materials,pp-bands have many outstanding advantages such as good physical and mechanical properties,convenient construction,light weight,high strength and low price.China is a country with frequent earthquakes and all previous earthquakes often destroyed a large number of masonry structures.Therefore,in view of the severe situation about earthquake resistance of masonry structures in china at present.It can provide a new idea for seismic strengthening of buildings by carrying out research on the reinforcement of pp-bands and has important engineering significance and research value.In view of the fact that scholars at home and abroad have not yet carried out a comprehensive and thorough study on the reinforcement technology of pp-bands.Its reinforcement mechanism,mechanical analysis model and the calculation formula of the shear capacity after reinforcement are still unclear.Therefore,a series of quasistatic tests and numerical simulation studies have been carried out in this paper.The main research work is as follows.1.In this paper,a two-story masonry building that had experienced JiujiangRuichang earthquake is selected and the cross wall of the bottom layer is used as the research object.Many masonry wall pieces are built according to the proportion of 1:2 and 6 of them were selected for key study.The mechanical properties of the unreinforced wall and the wall with different reinforcement modes such as development of crack,failure pattern,shear capacity,hysteretic curve,skeleton curve,stiffness degradation curve,ductility,energy dissipation capacity are compared and analyzed.The results show that the seismic performance of the wall pieces after the reinforcement of the pp-bands and the cement mortar have been improved.The deformation capacity and the ductility coefficient of the wall are improved significantly after the reinforcement of the pp-bands.2.Based on the results of quasi-static test,the finite element simulation of the above-mentioned 6 pieces of masonry wall is carried out by using ABAQUS finite element software.The finite element model is established by bonding interface and compared the failure pattern,the stress distribution,the hysteresis curve,the skeleton curve with the results of masonry wall piece during the quasi-static test.It is proved that it is feasible to carry out numerical simulation of pseudo-static experiment by separated modeling scheme.3.The factors that influence the shear capacity of the masonry wall are summarized and analyzed.Based on the previous experimental results and numerical simulation results,the reinforcement mechanism,mechanical analysis model and calculation formula of shear capacity which are suitable for the reinforcement of ppbands are derived.The calculated value of this formula is in good agreement with the quasi-static test value and the numerical simulation value.Its error is between 3% and 7% which can meet the requirements of practical engineering application.So it can provide reference and guidance for practical engineering application.