Risk Analysis of a Long-Distance Pipeline System in a Mountain Area Subjected to Multi-Hazards II: The Application

In mountain areas, the pipeline system is friable to multi-hazards such as: (1) the rainfall-induced flood and landslide; (2) the deterioration of the pipe materials due to the erosive effects of soil, gas, and wastewater inside or outside the pipe, and; (3) improper municipal construction. In the second of a series of papers on the risk analysis of a pipeline in a mountain area, the risk analysis models of rain-caused landslide and rain-induced flood are applied to evaluate the safety grade of the pipeline system. The extreme value distribution functions of the rain-induced flooding in different rainfall recurrence intervals are modeled by taking into account the terrain features and surface runoff of a specific gully, and also the statistics of the rainfall records in the recent 30 years in Chongqing. Taking into account the multi-damage modes of the pipe under multi-hazards, a comprehensive hierarchical model for the risk assessment of the pipeline is proposed. In the end, the application of the present model in Chongqing is given approval of its practicability.