Response of Single Plane Reinforced Concrete Cable-Stayed Bridge with Prestressed Deck under Blast Load

Abstract

Studies on cable-stayed bridges exposed to blast loads encounter significant challenges arising from the complex interaction among different structural elements. Despite extensive investigation into how buildings respond to explosive loads, there is limited literature on the dynamic response of prestressed concrete bridge decks to blast loads. Single plane cable stayed bridges are very sensitive to cable loss or degradation. This study investigates the response of a prestressed concrete cable-stayed bridge with a single plane under blast loads, utilizing a comprehensive Finite Element (FE) model that incorporates nonlinear effects. The investigation considers blast weights of 230 kg, 680 kg, and 2270 kg of TNT. The analysis reveals that even small explosions cause damage to the deck, with more significant effects observed under higher blast loads, resulting in a damaged region measuring 12 m x 10 m with a 2270 kg TNT weight. Forces in cables near the detonation point increase by 19% during a 2270 kg TNT explosion. Notable changes are observed in pylon moments under different explosion charges. Maximum Bending Moment (BM) values are observed at the base under dead loads, while BMs at mid-height increase under various blast weights, with no discernible change at the base. This study provides valuable insights for designers, emphasizing the importance of incorporating explosion-resistant design principles into cable-stayed bridges.

Keywords

• cable-stayed bridge
• structural response
• prestressed concrete
• blast load