Research On Mechanical Properties Of H-shaped Aluminum Alloy Members With Web Openings And Their Spatial Grid Structure

Aluminum alloys are widely used in various large-span space structures because of their lightweight and corrosion resistance.The Tamco system is the most widely used in engineering.It consists of three parts: gusset plate,H-shaped member,and bolts,but the gusset plate is only connected to the upper and lower flanges of the H-shaped member,not the web of the H-shaped member.Aluminum alloy material strength is not fully utilized.In order to overcome the existing deficiencies,consider using the H-shaped cross-section form with openings in the web to facilitate pipeline crossing,reduce self-weight,and save costs.Most of the researches on aluminum alloy components focus on considering the influence of section form,material type,etc.,on the mechanical properties of components.However,the research on the mechanical properties of aluminum alloy open-hole components is still relatively scarce.It is necessary to conduct in-depth research on the mechanical properties of H-type aluminum alloys with web openings.The main research results of this paper are as follows:1.Twenty H-shaped aluminum alloy members with web openings were designed,of which six were used for an axial compression test,six were used for an eccentric compression test,and eight were used for a pure bending test around the strong axis.The test results show that:(1)For the H-shaped aluminum alloy specimens with web openings under axial compression,the slenderness ratio affects the failure mode of the opening members.When the slenderness of the specimen is small,the strength of the specimen is damaged,and the bearing capacity of the specimen is controlled by its net section.When the slenderness of the specimen is relatively large,the overall instability of the specimen occurs,and the bearing capacity of the specimen is controlled by its stability coefficient.(2)For the H-shaped aluminum alloy specimens with web openings under bias,the specimens suffer from bending buckling failure in the eccentric direction,and the small slenderness ratio specimens are acco MPanied by local buckling.The effect of opening on the bearing capacity of the specimen under abnormal pressure is smaller than that under axial compression.The reduction range is basically the same as the reduction range of the net section resistance moment of the open-hole specimen around the strong axis.2.The accuracy and effectiveness of the model in the stability of H-shaped aluminum alloy members with web openings are verified by the co MParative analysis of the finite element results and the ultimate load and failure mode of the corresponding tests.A parametric analysis of various factors affecting the stable bearing capacity of components(including mesh size,initial bending,slenderness ratio,width-to-thickness ratio,opening parameters,etc.)is carried out through numerical simulation.3.The design method of the H-type aluminum alloy axial compression and biasing members with web openings is studied,and the calculation formula of the stability coefficient is given based on the assumption that the members are deformed according to the half-sine wave.Co MPared the suggested formulas given in this paper with the Chinese standard,the results show that the suggested formulas proposed in this paper have a curve close to the lower envelope,which is safe and can be applied to practical projects.4.A simplified modeling method of the H-shaped aluminum alloy space mesh with web openings is proposed and modeled,and the accuracy of the modeling method of the H-shaped aluminum alloy reticulated shell with web openings is verified.After that,the parametric analysis of the H-type aluminum alloy reticulated shell with web openings was carried out,and the design methods and suggestions for the H-type aluminum alloy reticulated shell with web openings were given.