Impact of Continuous Cable-Strut Joints on the Anti-Progressive-Collapse Performance of Suspended-Dome Structures

Abstract

In suspended-dome structures, cable-strut joints can be categorized into discontinuous joints and continuous joints. In calculations, the discontinuous joints can be treated as hinge joints. However, in the event of a cable breakage, the continuous joints might experience slip and detachment phenomena. Simplifying continuous cable-strut joints as hinge joints for calculation purposes can result in a significant discrepancy from the actual load-bearing state of the continuous joints. In fact, under the scenario of cable rupture, the continuous cable-strut joints might undergo slip and detachment. This could influence the formation of new tension paths within the cable support system, thereby affecting the anti-collapse performance of the suspended-dome structure. Therefore, this paper investigates the influence of the slippage and detachment of continuous cable-strut joints on the anti-progressive collapse performance of suspended-dome structures through joint tests, numerical simulations, and theoretical analyses. Firstly, two cable-strut joint test models were constructed. Apart from the difference that one uses a discontinuous cable-strut joint and the other a continuous cable-strut joint, all other conditions were kept identical. Research was conducted on the hoop cable failure test. The results indicate that the slippage and detachment of continuous joints hinder the formation of new tension paths in the lower cable-strut system. Structures using continuous cable-strut joints have lower anti-collapse capabilities compared to those using discontinuous cable-strut joints. Secondly, a simplified numerical simulation algorithm for cable-strut joints’ slippage and detachment is proposed. This algorithm only considers the support of struts to the upper structure and uses an Abaqus subroutine to achieve an equivalent simulation of the slippage and detachment phenomena of continuous joints during the finite element computation process. Then, using this algorithm, a progressive collapse analysis of suspended domes using continuous cable-strut joints was carried out. It was found that for suspended domes with continuous cable-strut joints, the slippage and detachment of the cable-strut joints are extremely detrimental to forming new tension paths, making the structure more susceptible to a progressive collapse. Lastly, using the resistance index, a quantitative analysis was conducted on the anti-collapse carrying capacity of suspended domes using both continuous and discontinuous cable-strut joints.