| Aluminum alloy is widely used in the field of building structure,which has the advantages of light weight,high strength and good corrosion resistance.However,the elastic modulus of the aluminum alloy is about 1/3 of the steel.Compared with the steel structure,the aluminum alloy structure has more outstanding stability.At present,the domestic research on the problem of Aluminum Alloy axial compression stability has achieved fruitful results,but the research is mostly for 6061-T6,5083-T6 and 6082-T6 weak hardening,hardening of the alloy is lack of research,especially has not had a strong stability test on component hardened alloy,China's " Code for design of aluminum alloy structure" GB50429-2007 on the hardening of alloy component design requirements is only based on the results of numerical simulation.At the same time,GB50429 is based on the analysis of H aluminum alloy axial compression member,which provides the calculation method of stability coefficient.In addition,the formula of the related research at home and abroad is not consistent with the provisions of the GB50429,and it is not enough to support the formulation of norms.Therefore,based on the axial compression thickness ratio of plates meet the specification limits,local buckling does not occur before buckling occurs,a series of stable pressure component hardening alloy on the typical section and the weak hardening alloy shaft,mainly to do the following work:?1?The type of alloy of wood properties includes two kinds of 6061-T4 alloy and 6061-T6 alloy commonly used in engineering.It can be through the tensile test specimen with increasing strain,6061-T4 alloy stress in non linear elastic stage has obvious growth;in addition,the ultimate strain of 6061-T4 alloy is larger than that of 6061-T6 alloy,but its ultimate stress is less than 6061-T6 alloy.?2?Experimental study on the stability of 60 aluminum alloy axial compression specimens.The sample type of alloy includes 6061-T4 and 6061-T6.The section types of the specimens mainly include five typical types,H,square,round,groove and corner.The effects of different alloy types,section types and slenderness ratio on the stability,bearing capacity,failure forms and deformation properties of aluminum alloy axial compression specimens were investigated.The test showed that: whether 6061-T4 or 6061-T6 Aluminum Alloy hardening hardening Aluminum Alloy axial compression specimens,specimens with the increase of the slenderness ratio,the ultimate load will be reduced,the initial stiffness will be reduced,the deflection speed up development.?3?Based on the comparison of the proposed constitutive model of aluminum alloy in China and Europe,a constitutive model is proposed,which is more suitable for theoretical analysis.?4?A finite element Aluminum Alloy axial compression model using the finite element software ANSYS,and using the proposed constitutive model,found that they matched well after the comparison between numerical simulation results and experimental results,to verify the accuracy of finite element method.?5?Test and analysis of parameters based on the results,we can find that the axis symmetric section,width thickness ratio of plate or pipe section diameter thickness ratio of column curves of pressure components Aluminum Alloy shaft two type of alloy have little impact in the design can not take into account the influence of the above two parameters on the stability bearing capacity of axial compression members.Based on the parametric analysis,the geometric imperfection coefficient method,comparing the calculation results,the suggestions and test parameters and analysis results are better,meet the design requirements of precision engineering.?6?For monosymmetric section two alloy type?groove type and T type?of axial compression,calculation formula of non symmetry coefficient ?as section is given in this paper proposed,the calculation results the proposed formulas agree well with the results of finite element analysis,and the comparison of test results is very safe and can be used as the basis for the design of.In addition,the angular cross-section of the shaft two alloy type pressure component,section effect of non symmetry on the buckling stress is very small,but does not consider the effect of non symmetry section of diagonal section of axial compression buckling stress.?7?Through the experiment and finite element calculation results verify the monosymmetric section?groove,angle gauge?using conversion and torsion effect of long feasibility and accuracy of slenderness ratio,determine the column curves of monosymmetric section Aluminum Alloy flexural torsional buckling of axial compression members. |
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