Disproportionate collapse analysis of cable-stayed steel roofs for cable loss

Abstract

Disproportionate collapse has been identified lately as a real cause of failure for structural engineering projects. Rare and unexpected, the phenomenon of disproportionate collapse usually results to many fatalities and thus, its analysis and mitigation is deemed necessary. This work describes the analysis of a cable-stayed steel roof under the scenario of a cable loss. The event of a cable loss is assumed to be brittle, while relevant recent recommendations suggest the application of a scaled equivalent static force at the points of the anchorage of the cable but in the opposite direction of the original cable force. In this paper, three different conditions have been considered in order to study the effect of the cable loss into the overall structural response of a typical cable-stayed roof; the level of the equivalent nodal load in the opposite direction of the original cable force varies. The steel structure of the roof, in its complexity, closer to responding as a cable-stayed bridge rather than a steel roof provides a useful template for conclusions; several topics regarding disproportionate collapse and cable losses are discussed.

Failure Test of a Suspendome Due to Cable Rupture

“…In suspendomes, tensioned cables may experience accidental damages or rupture scenarios during their service period due to construction errors or human factors. In addition, cable failure will not only result in the sudden failure of structural components but also involve a considerable unloading effect on the remaining structure owing to the high-tension state (Wang and Bai [12]; Gerasimidis and Baniotopoulos [13]). Chen and Sun [14] explored the internal force distribution pattern and the nonlinear stability behavior of suspendomes before and after cable failure by directly running static simulation with or without ruptured cable pieces.…”