Local buckling of thin-walled circular hollow section under uniform bending

This article presents a semi-analytical finite strip method based on Marguerre’s shallow shell theory and Kirchhoff’s assumption. The formulated finite strip is used to study the buckling behavior of thin-walled circular hollow sections (CHS) subjected to uniform bending. The shallow finite strip program of the present study is compared to the plate strip implemented in CUFSM4.05 program for demonstrating the accuracy and better convergence of the former. By varying the length of the CHS, the signature curve relating buckling stresses to half-wave lengths is established. The minimum local buckling point with critical stress and corresponding critical length can be found from the curve. Parametric studies are performed to propose approximative expressions for calculating the local critical stress and local critical length of steel and aluminum CHS.

STUDY ON ADJUSTABLE CONNECTOR OF RECIPROCAL FRAME

In this paper, we design an adjustable connector of reciprocal frame, and a three-dimensional solid model of this connector with Circular Hollow Section has been created in the FEM software Abaqus CAE to study its mechanical properties. When the plastic hinge is formed at the end of the Circular Hollow Section, the connector is still in an elastic state. It is concluded that the adjustable connector of reciprocal frame has high strength and rigidity, realizing the goal for designing higher connector strength over Circular Hollow Section strength. Then parametric analysis is used to analyse the influence of the connector about each part on the mechanical properties, and the flexural rigidity of the connector has been derived. A three-dimensional wire model of reciprocal frames has been created in the FEM software Abaqus CAE, and a full-scale test model of the structure is designed. The numerical simulation results agree well with the test results. It is verified that the reliability of the modeling method and the accuracy of the connector mechanical model.