ABSTRACT
Based on the finite element (FE) method, the simulation of the complex intersecting joints of the large-span spatial steel structure at Taiyuan Botanical Garden is performed to investigate mechanical properties such as stress distribution, failure mode, and ultimate bearing capacity. Stress concentration analysis is performed for the typical Y-type intersecting pipe joints, and 75 groups of FE models are computed to explore the stress distribution and stress concentration factor (SCF) of the joints under three working conditions of axial force, bending moment, and axial force with bending moment. Three formulas are derived for calculating the SCF appropriate for Y-type pipe intersecting joints. It is found that the ultimate bearing capacity of the joints satisfies the requirements of the relevant specifications; the peak stress appears at the intersection line of each branch pipe; the main pipe wall thickness has a great influence on the stress concentration, and the influence of the stress concentration could be reduced by increasing the main pipe wall thickness. There is good agreement between the calculated result of the multi-factor fit formula and the FE analysis result, which verifies the reliability of the fitting formulas.
