Protective water curtains as wave attenuators for blast-resistant tunnels

Abstract

Tunnels, as highly cost-demanding infrastructures which facilitate the transportation of people and goods, have been a target of terrorist attacks within the past few decades. The significance of the destructive impact of explosives on these structures has resulted in research on the development of blast-resistant design approaches. In this paper, water curtains are proposed as a blast-resistant system due to the established performance of water against explosives in free fields in previous studies as well as its capability to mitigate the potential incoming fire after an explosion. A parametric study was conducted for this purpose, considering the effects of curtain thickness, the distance of the curtain from the tunnel opening, and the amount of TNT charge. Accordingly, fifty-two finite element (FE) models were created in the FE package ABAQUS to investigate the performance of a water wall in a typical tunnel through the Eulerian approach to simulation. The water curtains had four different thicknesses and were located at three different distances from the reference point. TNT explosive charges were placed at the tunnel opening with four different masses. The thicker walls nearer to the tunnel opening were found to be more effective. However, the peak pressure reduction in all charges was in a desirable range of 53 to 80%. The parametric study also illustrated that the peak pressures were more sensitive to wall thickness rather than TNT charges mass and the wall distance from the explosives. We anticipate this preliminary study to be a starting point for the further development of the concept of water curtains for blast mitigation.

Analysis of the Tunneling Blast Safety Criterion Based on Longitudinal Shocks

“…Te drilling and blasting method has become the most commonly used construction method in tunnel engineering construction. However, although the blasting method has brought signifcant changes to tunnel engineering construction, vibration disasters are also a major concern, especially due to the seismic efect of blasting, which is the foremost disaster [2][3][4][5][6]. Terefore, predicting the propagation law of blasting vibration waves has become a crucial aspect of blasting problems research [7].…”

Simulating the response of buried structures to external blast loads: Methods, challenges, and advances

“…Protecting the tunnels from internal blasts usually requires special considerations in structural design or protective systems. For instance, Kehsavarz et al 29 proposed a water curtain as a blast‐resistant system and investigated the impact of the wall thickness and standoff distance as well as the amount of TNT charge. The results showed a linear relationship between the distance of a thicker wall from the tunnel opening and its efficiency.…”