Study On Shear Failure Mechanism Of Polyurethane Foam Steel Frame Metal Panel Integrated Wall Panel

In recent years,the construction market has had higher and higher standards for building products.How to complete the construction with the shortest construction cycle,the lowest cost and the least construction waste is particularly important.Among them,prefabricated buildings have the advantages of easy installation,less construction noise,shorter construction period and lower construction cost.The polyurethane foam-steel framemetal panel integrated wall board mentioned in this paper(referred to as RSM integrated wall in this paper)is composed of steel frame as the main body.The metal plate is fixed on both sides of the steel frame by screws,and the polyurethane foam is injected between the metal plates on both sides.In practical application,the RSM integrated wall is placed in the beam and column frame of the house and connected by connecting parts.As there is no mature specification,procedure and standard for RSM in China,the synergy between steel frame,metal plate and polyurethane is not considered in the actual engineering design process,which greatly underestimates the actual performance of RSM integrated wallboard.Therefore,the shear failure mechanism of RSM integrated wallboard is studied in this paper.In this paper,the shear capacity and failure mechanism of the wall are analyzed through the pseudo-static test.The analysis shows that the RSM integrated wall relies on the steel plate torsional deformation,frame deformation and polyurethane deformation to jointly bear the horizontal load.Under the action of low cyclic cyclic horizontal load,the steel plate is in the state of deformation-recovery-reverse deformation.Initially,all components are in the elastic stage,with the increase of load,steel plate damage,frame yield,until steel frame damage,horizontal bearing capacity rapidly decreases,wall damage;Reducing the ratio of height to width and encrypting the spacing of self-tapping screws make the steel plate damage later and the overall damage faster;The thickened steel plate,the thickened side column section thickness and the strengthened polyurethane all make the metal plate tear later.Changing metal plate to aluminum plate,increasing vertical load or removing tensile parts have no effect on wall failure mechanism.The steel plate will be deformed out of plane after the addition of steel strip.By analyzing the hysteretic curve and skeleton curve,the shear capacity of the wall was compared.Compared with the pure frame,the shear capacity of the steel frame after the installation of steel plate was increased by 21%.The shear capacity of the wall(standard wall)increased by 45% after polyurethane filling;The shear capacity of the perforated wall is reduced by 19%.Reducing the ratio of height to width increases the shear capacity of wall by 36%.The thickened steel plate increases the wall shear capacity by 75%;When the metal plate is changed to aluminum plate,the shear capacity increases by 3%,basically unchanged;The thickened side column section increases the shear capacity of the wall by38%.The shear capacity of the wall was increased by 14% by polyurethane.The spacing of self-tapping screws increases the shear capacity of the wall by 34%.The shear capacity of the wall is increased by 33% by adding steel belt.The shear capacity of the wall decreases by 7% and 3%,respectively,when the tensile parts are removed or the vertical load is increased.By analyzing the monotonic load displacement curve,the initial shear stiffness of the wall was compared.Compared with the pure frame,the initial shear stiffness of the steel frame after the steel plate was installed was increased by 142%.The initial shear stiffness of the wall(standard wall)increased by 233% after polyurethane was injected.The initial shear stiffness of the holed wall is reduced by 141%.Reducing the ratio of height to width increases the initial shear stiffness of wall by 30%.The thickened steel plate increases the initial shear stiffness of the wall by 22%.The initial shear stiffness was reduced by 41%when the metal plate was changed to aluminum plate.The initial shear stiffness of the wall increases by 8% after the section of the side column is thickened.The initial shear stiffness of the wall increased by 8% after the polyurethane was strengthened.After the spacing of self-tapping screws is encrypted,the initial shear stiffness of the wall increases by 6%,which is basically unchanged.The initial shear stiffness of the wall increased by 8% after the steel strip was added.The initial shear stiffness of the wall decreases by 7% and 6%respectively when removing the tensile parts or increasing the vertical load,which is basically unchanged.Compared with the pure frame,the energy dissipation capacity after the installation of steel plate is increased by 260%;The wall filled with polyurethane improved 333% in this respect;After opening holes,the wall is reduced by 52% in this respect;Reduce the height to width ratio of the wall in this respect by 7%,basically unchanged;The thickened steel plate increased by 14% in this respect;After the metal plate is changed to aluminum plate,the wall is improved by 14% in this respect;The thickened side column section improves the wall by 47% in this respect;Reinforced polyurethane improves the wall by 12% in this respect;Encrypted self-tapping screw spacing increases the wall by 9% in this respect;Add steel belt to increase wall width in this aspect by 20%;After removing the tensile parts or increasing the vertical load,the wall will decrease by 7% and 1%,respectively,basically unchanged.