Dynamic responses of tunnel lining structure under internal blasts
Zhao Debo1,2 Chu Cheng 3 Su Dong1,2
1. College of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518000, China；
2. Key Laboratory of Coastal Urban Resilient Infrastructures(MOE), Shenzhen University, Shenzhen 518000, China；
3. Rocket Army Engineering Design and Research Institute, Beijing 100000, China
Abstract：To investigate the dynamic responses of tunnel lining structure under internal blast loading accurately, an “explosive-air-structure-soil” coupled finite element (FE) model was established and verified by explosion test results of a full-scale tunnel lining structure. During the ignition phase, a On-dimensional (1D) axisymmetric model with fine mesh was adopted to calculate the propagation of the explosion wave in free space, and the result of the 1D model was mapped to the three-dimensional (3D) fluid-structure coupled model to calculate the interactions among explosion wave, lining structure and soil just before the explosion wave reached the lining structure. The calculated overpressure histories and failure modes of the lining structure fit well with experimental results, indicating the applicability of the FE model and the mapping technique. The characteristics of the explosion wave propagation in the lining structure were analyzed based on the FE model. The results indicate that under the eccentric explosion condition the explosion wave converges at the far-end for a long duration, and the lining structure at this zone, which undergoes large overpressure and impulse, should be regarded as the weak region in the anti-explosion design.
