Research On Stability Of Partially Encased Composite Wall

Partially encased composite walls（PEC walls）have been widely used in the field of prefabricated buildings.In recent years,it has been gradually applied in building structures.However,the researches on the stability performance remain to be improved.In this paper,the stability performance of PEC wall under axial compression is studied.The research shows that the calculated values of the stability curve formula are in good agreement with the finite element results,which can provide references for related research and practical engineering applications.In this paper,the finite element analysis model is established by using the finite element software ABAQUS.In chapter 2,the parameter setting and modeling process of the finite element model are introduced in detail,the accuracy of the model was verified by comparing the linear buckling load with the Euler critical load and the ultimate bearing capacity with the existing tests.In chapter 3,the ultimate bearing capacity of PEC shear wall under axial compression is analyzed by parameters,and the influence of each parameter on the ultimate bearing capacity is investigated,including:the calculated length,material strength,steel plate thickness of the main steel,the cross-section size of the components.In the process of parameter analysis,the control variable method is used to study the influence of each parameter on the stability of PEC shear wall,and the force characteristics and regulations are summarized.In chapter 4,a formula for calculating theφ-λcurve of the axial compression stability of PEC shear walls is presented.Then,based on the stability theory of the combined structure,the equivalent strength f _EQ and equivalent elastic modulus E_EQ of the combined section are comprehensively determined according to the composition of concrete and main steel parts in the combined section,and the regularized slenderness ratioλ_n of the PEC wall components is derived.Then,based on the results of finite element analysis,the axial stability curve of PEC wall is drawn,and the stability curve of four types of sections of steel structure is compared with the stability curve of PEC wall,the regulation is summarized,and the calculation method suitable for the stability curve of PEC wall components is found.Finally,based on the parameter analysis results,the influence of each component parameter on the stability curve of PEC wall is summarized,and the key component parameters are introduced as control variables in the calculation formula of the axial compression stability curve of PEC wall,and the calculation formula of the axial compression stability curve of the"three-stage"PEC wall is proposed based on the characteristics of the mode of the components under different calculated lengths.In chapter 5,the concrete thickness of PEC shear wall is studied,and the influence of load condition,web thickness,length and section height on in-plane stability of web is investigated.The concrete thickness needed to keep the in-plane stability of webs is studied under each parameter.