Disproportionate collapse of a cable-stayed bridge

Abstract

The disproportionate collapse of an existing cable-stayed bridge was investigated at the numerical level by employing a validated model from the literature and the applied-element method. An earthquake input was used for the numerical simulations and applied at increasing intensity to assess the bridge response. The role of redundancy in the bridge structural scheme was proved to be a strategic measure for avoiding disproportionate collapse and improving robustness. Therefore, an alternative configuration of the structural scheme was assessed as a possible countermeasure to improve the response of the cable-stayed bridge by providing different loading paths against disproportionate collapse. New redundancy indices that account for the system reserve resources are also introduced.

Collapse prognosis of a long‐span cable‐stayed bridge based on shake table test and nonlinear model updating

“…Each cable is modelled by one truss element and the sag effects are considered by the Ernst method 26 . Such a modelling strategy is also commonly used in many existing studies 10,11,17,26 . The steel hollow section girder, which remained elastic during the tests, 11 is modelled by elastic shell elements.…”

“…26 Such a modelling strategy is also commonly used in many existing studies. 10,11,17,26 The steel hollow section girder, which remained elastic during the tests, 11 is modelled by elastic shell elements. The reinforced concrete main towers and sider piers are modelled by nonlinear four-node multi-layered shell elements, which consist of concrete layers and smeared rebar layers.…”

“…Therefore, specialised analyses based on advanced numerical methods are needed for performance evaluation and collapse simulation of these bridges. There are some studies on the collapse progress simulation of long‐span cable‐stayed bridges 5,8,15–17 . Lin et al 5 adopted multi‐layered shell elements to account for the failure process of the beam‐column conjunction of a bridge pylon.…”

“…Zhou et al 16 compared the failure process of a multi‐span cable‐stayed bridge under two different ground motions using LS‐DYNA. Domaneschi et al 17 built the FE model of a cable‐stayed bridge with a main span of 260 m and simulated the disproportionate collapse of the bridge based on the applied element method. However, most of the numerical models used in the existing studies are based on the design documents of the bridges, which do not consider the actual damage state of the bridge structure.…”

“…There are some studies on the collapse progress simulation of long-span cable-stayed bridges. 5,8,[15][16][17] Lin et al 5 adopted multi-layered shell elements to account for the failure process of the beam-column conjunction of a bridge pylon. The earthquake-induced collapse simulation of a super long-span cable-stayed bridge with a main span of 1,500 m under a long-period ground motion was successfully conducted based on the open-source FE software OpenSees.…”