Numerical simulation of a scaled composite cable-stayed bridge subjected to extreme loading

Due to important rules of bridges for transportation in daily lives, the serviceability of them are indicated as high level priority after natural hazards or human-made problems. Moreover, increasing the number of accidents during the last decades leads to increasing the importance of their stability against extreme loading. In this study, Numerical simulation of a scaled composite cable-stayed bridge subjected to extreme loading has been performed. In first part of study, the scaled model is subjected to 418.4 kJ, 2092 kJ, 4184 kJ and 6276 kJ energy respectively in the same location (0.5 cm from the bridge tower and 1 cm above the deck). In second part of study, the constant 2092 kJ energy is imposed in three different locations of the scaled bridge (0.5 cm from the bridge tower and 1 cm above the deck, the middle of main span and 1 cm above the deck, at the end of main span and 1 cm above the deck). In the third part of study, the amount of extreme loading is kept in an equivalent value and location (2092 kJ energy in the middle of main span and 1 cm above the deck); however, the number of cables have been reduced to half and one-third of the original number. The effects of different amounts of extreme loading and failure propagation are examined and illustrated in first part. The critical segments of the bridge against an extreme loading and effect of extreme loading locations have been examined in second part. The number of cables’ effect in failure propagation has been investigated in last part. Moreover, examining the failure propagation in different cases is proven that the pylon, the connection area between pylon and main span as well as the cables are the critical parts of the bridge. Failure in these critical parts could result in total failure of the bridge; however, extreme loading near to the horizontal load bearing system could result in instability of structure and partial failure. Separation of the bridge in different parts and providing the alternating load path are recommended as a proper way to increase the bridge’s stability against extreme loading

Keywords:

Cable-stayed bridge , Numerical simulation , Nonlinear analysis , Extreme loading , Failure propagation