Structural Stability Analysis of Steel Tubular Scaffold with Couplers Based on Direct Analysis Method

Abstract

Direct analysis method (DAM) is a second-order nonlinear analysis approach widely used for its high accuracy and simple flow. It is suitable for pinpointing the internal force response and nonlinear behavior of steel tubular scaffold with couplers (STSC), which has large initial defects arising from repeated use. This paper firstly quantifies the initial defects of steel tubes of the scaffold and draws the column curves of the tubes with different initial bending and residual stresses. On this basis, a reference value was derived for the overall initial defect of the tubes with different initial bending. Through a calculation example, a finite-element model was established in view of the overall initial defect, the initial defects of components, and the nonlinear semi-stiffness of nodes and the DAM flow was introduced for the STSC. The calculation example verifies the rationality of the reference value for the overall initial defect, making it easier to apply the DAM to actual engineering.