Study On Structural Mechanical Performance And Design Method Of An Innovative Sandwich Wall Panel

The physical and mechanical properties should be considered in the study of the new enclosure structure.In this paper,a new type of sandwich wall panel,Fiber Cement Pressure sandwich wall panel(hereinafter referred to as FCP sandwich wall panel),is designed with fiber cement pressure board as the cover panel.After the completion of the physical performance test,the lateral mechanical properties of the wallboard,the influence on the lateral mechanical properties of the main structure,the bending mechanical properties under uniform load,the failure mechanism and the corresponding design methods are deeply studied.The main contents and results of this paper are as follows1.The lateral mechanical properties of FCP sandwich wall pane under horizontal low cycle cyclic loading are studied.Taking the stud spacing and window opening as the research parameters,the main failure modes of FCP sandwich wall panels with different parameters,the basic form and development law of load-rotation curve,and the basic causes of pinch phenomenon are analyzed;According to the test results of lateral mechanical properties,the effects of different parameters on the lateral bearing capacity,stiffness,ductility,stiffness degradation and energy dissipation capacity are analyzed.2.The simplified calculation model and finite element analysis model of FCP sandwich wall panel are established.Based on the equivalent calculation model of strut and tie,two-column spacing model and shear flow model are used to simplify the analysis,and the simplified calculation model of FCP sandwich wall panel is established;The dynamic time history analysis of steel frame structure with wall panel is carried out by using OpenSEES finite element analysis software.It is proved that FCP sandwich wall panel can effectively reduce the top displacement and inter-layer displacement angle of steel frame under earthquake action.3.The bending mechanical properties of FCP sandwich wall panel under uniform load are studied.Based on the experimental study of full-scale bending mechanical properties of FCP sandwich wall panel,the basic failure mode and the change law of bending bearing capacity of the panel are analyzed with stud spacing,connection mode,window opening and positive and negative direction loading as research parameters;Through the analysis of the strain size and development law of cold-formed thin-walled steel stud,the failure mechanism of FCP sandwich wall panel in the whole bending process is further revealed.4.The finite element model of FCP sandwich wall panel is established.The material non-linearity,geometric non-linearity and interaction between components are considered in the calculation model,and the calculation results are verified by the test results.Based on the results of finite element analysis,the typical failure modes and the corresponding load displacement curves are analyzed,and the load displacement curve of the wall panel under the yield failure mode of the stud is deeply studied.The load-displacement curve is divided into four stages,and the stress size and distribution law of the FCP sheathing and the steel stud at the characteristic points of each stage of the curve are analyzed,The failure mechanism of FCP sandwich wall panel in the whole bending process is revealed.5.The bending design method of FCP sandwich panel is established.Based on the basic theory and stress principle of sandwich structure,the calculation methods of bending stiffness,normal stress and shear stress of section and shear distribution coefficient of core material of FCP sandwich wall panel are obtained;Based on Mindlin plate equation and Hoff's variational theory,and taking into account the contribution of steel stud and FCP sheathing to the bending stiffness,the deformation method of FCP sandwich wall panel is obtained.The calculated results are in good agreement with the finite element analysis results.