Stability Analysis Of Aluminum Alloy Biaxial Compression Members

The structure of Aluminum alloy has many advantages,such as light weight,low maintenance and high recovery rate,which is more and more widely used in bridge and building structures.However,the research on the structure of aluminum alloy started late in China.There is not relevant research on the Stability analysis of the Bidirectional pressure-bending Specimen that made of aluminum alloy at home.Study on the Stability analysis of the Bidirectional pressure-bending Specimen that made of 6061-T4 aluminum alloy is based on numerical analysis.The experiment of the Stability analysis of the Bidirectional pressure-bending Specimen that made of 6061-T6 aluminum alloy needs more work,which provides a basis for theoretical analysis and design formula.The 6061-T4 and 6061-T6 aluminum alloy is used as the typical representative of the weak and hardening aluminum alloy respectively.Therefore,it is necessary to study the Stability of the pressure-bending Specimen that made of 6061-T4 type and 6061-T6 type aluminum alloy,which can promote the application of the structure that made of aluminum alloy.The Stability calculation formula of the Bidirectional pressure-bending Specimen that made of aluminum alloy is a linear combination between the formula of axial compression Specimen and Stability calculation formula in the design code of the structure of Aluminum alloyGB50429-2007.The Coefficient of correction in the Stability calculation formula of the Bidirectional pressure-bending Specimen that made of aluminum alloy is same as the calculation formula of curved Specimen.Therefore,it is necessary to determine the correction coefficient of the Stability calculation formula of the Bidirectional pressure-bending Specimen that made of aluminum alloy.The constitutive model and the finite element analysis model of 6061-T4 and 6061-T6 shape aluminum alloy were selected on the basis of the experimental study.whether the Stability calculation formula of the pressure-bending Specimen in the GB50429 can apply for the pressure-bending Specimen that made of 6061-T4 type and 6061-T6 type aluminum alloy On the basis of parameter analysis.And there are some suggestions about how to gain the correction coefficient in the Stability calculation formula of the pressure-bending Specimen.whether the Stability calculation formula of the Bidirectional pressure-bending Specimen in the GB50429 can apply for the Bidirectional pressure-bending Specimen that made of 6061-T4 and 6061-T6 aluminum alloy on the basis of parameter analysis.as well as it is important for the Stability calculation formula that was modified of the Bidirectional pressure-bending Specimen that made of aluminum alloy to verify the reasonability.The main productions of this paper can be found in the following list:?1?The 92 texts of the aluminium beam-column,the 48 texts of the aluminium beam-column under unequal end bend and the 40 texts of the biaxial bending beam-columns that made of aluminum alloy were carried out.The main parameters are slenderness ratio and load eccentricity.the 6061-T4 and 6061-T6 shape aluminum alloy materials is related.The specimen section type contains H section,square tube and flat pipe section.This paper mainly studied the buckling form in the different types of Aluminum Alloy bending section under the different stress modes and the influence of various parameters on the bearing capacity and deformation performance.?2?The Influence factor of finite element model of the pressure-bending Specimen was studied.And it is necessary to identify the finite element model of pressure-bending Specimen.Based on the material test data,the constitutive relation of two kinds of aluminum alloy materials with 6061-T4 and 6061-T6 shape are selected.The finite element model of the pressure-bending Specimen and The experimental of the pressure-bending Specimen results were compared.The Experimental results show that the finite element analysis results are accurate and reliable and in this paper,the finite element analysis method can be used as a predictive the ultimate bearing capacity of the pressure-bending Specimen.Therefore,the experimental results are accurate and reliable,which can be used for parameter analysis.?3?Generally,In the GB50429 the capacity calculation formula of In-plane instability bearing of the pressure-bending Specimen is slightly conservative when it is applied for the curved Specimen that made of 6061-T6 type aluminum alloy.In this paper,The value of the correction factor ?₁ is suggested to gain 0.75 for the 6061-T6 aluminum alloy.The value of the GB50429 is reserved;The capacity calculation formula of In-plane instability bearing of the pressure-bending Specimen is excessively conservative when it is applied for the curved Specimen that made of 6061-T4 type aluminum alloy.The value of the correction factor ?₁ is suggested to change from 0.9 to 0.8,which will become more accurate.?4?In the GB50429,The capacity calculation formula of In-plane instability bearing of the pressure-bending Specimen is slightly conservative when it is applied for the pressure-bending Specimen and whose H section is subject to the strong axis bending.In the GB50429,The capacity calculation formula of In-plane instability bearing of the pressure-bending Specimen Can be used to guide the design of 6061-T4 and 6061-T6 aluminum alloy components;In the GB50429,The capacity calculation formula of In-plane instability bearing of the pressure-bending Specimen is excessively conservative when it is applied for the pressure-bending Specimen and whose H section is subject to the strong axis bending.The value of the correction factor ? is suggested to change from 0.7 to 0.55 for the 6061-T4 and 6061-T6 aluminum alloy that whose section is box,which becomes more accurate.?5?The test results of aluminium beam-column in the plane under unequal end bend were greater than the results of the design formula in GB50429,and the difference between the two data was within 20%,which indicates that the calculation formula of aluminium beam-column in the plane under unequal end bend in GB50429 is conservative,can guide the design of the 6061-T4 and 6061-T6 aluminum alloy.?6?The test results of aluminium beam-column out the plane under unequal end bend were greater than the results of the design formula in GB50429,and the difference between the two data was greater than 20%,which indicates that the calculation formula of aluminium beam-column out the plane under unequal end bend in GB50429 is conservative,can guide the design of the 6061-T4 and 6061-T6 aluminum alloy.?7?Based on the parameter analysis of Biaxial Beam-columns,the design formula in the GB50429 is verified and some reasonable suggestions are put forward.The results showed that the stability design method in the GB50249 is conservative for the H section and box section Biaxial Beam-columns,which shows that the calculation formula of GB50429 external bending stability can be used to guide the design of 6061-T4 and 6061-T6 aluminum alloy components;It is suggested that the precision of the GB50429 method in the design of 6061-T4 and 6061-T6 aluminum alloy biaxial bending member is improved with the proposed value of the modified coefficient and the recommended value of the influence coefficient.