Multi-conditional dynamic response of parallel multi-pipelines in the same tunnel based on leakage and explosion conditions - A case study of China-Myanmar tunnel pipelines

Abstract

The explosion of oil and gas pipelines, a severe incident, typically results in incalculable losses in terms of life, property, and environmental damage. To assess the impact of leakage and explosions on adjacent pipelines within a triple-tube tunnel, the TNT equivalent of the explosion was calculated based on leakage volume. Subsequently, a 3D nonlinear FE model for tunnel pipelines subjected to explosions was developed to analyze the influence of factors such as leakage area and blast center distance on the extent of damage to adjacent pipelines during an explosion. The concept of blast wall was introduced into the tunnel for the first time to evaluate its protective performance for adjacent pipelines under explosion conditions. This analysis considered factors such as height, material, and other relevant parameters. The results indicate that (1) the equivalent stress of adjacent pipelines rises with an increase in the leakage area of the gas pipeline, internal pressure of adjacent pipelines, and TNT equivalent. Conversely, it is inversely correlated with blast center distance, height, thickness of the blast wall, and the distance between the wall and the explosion center; (2) the primary factor influencing damage to the crude oil pipeline under the impact of blast load is the blast center distance. For the product oil pipeline, the main factors contributing to damage from explosion load impact are the blast center distance and leakage area; (3) due to its high internal pressure, thin wall thickness, and relatively lower strength, the product oil pipeline is more vulnerable to failure when subjected to an explosion compared to the crude oil pipeline. The implementation of a blast wall proves highly effective in preventing pipeline failure. This study provided theoretical reference for pipeline maintenance under tunnel explosion.