Department of Earthquake Engineering, Indian Institute of Technology Roorkee, India
Corresponding author. Rajarshi Das, Department of Earthquake Engineering, IIT Roorkee, 247667, India. Tel.: +917417304628; E-mail: [email protected].
Abstract: Although the application of the Alternate Path method has well proven its efficiency towards increasing the structural robustness of bare frame structures against progressive collapse, it should be further developed for bridge structures, and especially cable stayed bridges, as they are the only type routinely designed for cable loss phenomenon. The main objective of this paper is to analyse a cable stayed bridge for multiple types of cable loss phenomenon to develop a profound knowledge regarding the overall structural response to local failure and the possibility of a failure progression throughout the structure. This paper demonstrates numerical modelling and analysis of a typical cable stayed bridge through a nonlinear static procedure using SAP 2000. The response of the structural model is discussed for multiple types of cable loss cases to identify a definite progressive collapse pattern. Furthermore, a categorical investigation of the impact ratios was also done for different structural properties through a dynamic analysis to recognize the lack of robustness in the structure. The results indicate different design considerations for different elements of the structure and also a variation in the possibility of failure progression through the cable stayed model depending upon the location of the failed cables. The prevailing collapse type is discussed with some suggestions for a more robust design.