| The application of aluminum alloy materials in the support and hanger field is the first time in China.In order to promote the scientific and reasonable application of aluminum alloy materials in this field,based on the test and finite element parametric analysis,the mechanical analysis of the compression(axial compression and bending)components of the commonly used aluminum alloy support and hanger products is carried out in this thesis.The main research contents and results are as follows.Through the uniaxial tensile test of 12 new aluminum alloy materials(a high strength aluminum alloy material)and 6 6061-T6 aluminum alloy,it is found that the bearing capacity of the new aluminum alloy material is higher than that of 6061-T6 aluminum alloy,and the deformation of the new aluminum alloy material is smaller than that of 6061-T6 aluminum alloy in the plastic stage.The constitutive relationship curves of new aluminum alloy materials and6061-T6 aluminum alloy were compared by using the calculation method recommended by European aluminum alloy specification and Chinese specification,and its applicability to new aluminum alloy materials and 6061-T6 aluminum alloy was verified.The hardening exponent n was obtained by fitting the constitutive curves of the two materials.Six axial compression tests and eight bending tests were carried out on the I-shaped cross section of 6061-T6 aluminum alloy,considering the slenderness ratio and eccentricity.The instability type and load-displacement curve of the component were obtained through the test.The test found that the stable bearing capacity of the member decreased with the increase of slenderness ratio.With the increase of eccentricity,the bearing capacity of components decreases.For small-section components,the bearing capacity decreases by about 50% within the eccentricity of 10 mm,and the bearing capacity decreases with the increase of eccentricity.Based on the constitutive relationship in this thesis,the finite element software was used to establish the analysis model.By comparing the finite element analysis results with the experimental analysis results,it was found that the experimental data were in good agreement with the finite element analysis data,which verified the applicability of the finite element.The above finite element analysis method was used to analyze the expansion parameters of aluminum alloy support and hanger compression members,and a total of 835 finite element specimens were analyzed.The finite element specimen consists of two different cross-section types: the I-shaped cross-section with rolled edges and the complex H-section.Two different materials: new aluminum alloy material,6061-T6 material.The influence of section size,slenderness ratio,eccentricity,initial defect,instability direction,web opening and residual stress on the compression member of aluminum alloy support and hanger is considered.The finite element simulation results show that the influence of section size on the stability coefficient of axial compression member is small.With the increase of slenderness ratio and eccentricity,the ultimate bearing capacity of members decreases continuously.The initial defect has a great influence on the axial compression member.With the increase of initial defect,the ultimate bearing capacity decreases.The larger the initial defect is,the greater the decrease of bearing capacity is.The initial defect has a relatively small influence on the bending member.The web opening has great influence on the ultimate bearing capacity of short columns.The finite element calculation results are compared with the calculation results of the advanced codes in China and abroad,and it is found that the standard method is conservative.Based on the recommended formula of the current code in China,the relevant parameters are adjusted and corrected,and the calculation methods of the compression members with I-section and complex H-section are proposed,which can provide reference for designers. |
PDF Full Text Request