Анализ риска аварий магистральных трубопроводов на сейсмоопасных участках
Strong earthquakes can cause fires and explosions on pipelines, as well as the emergence of environmentally dangerous leakages of transported products. This paper presents a methodical approach in assessment of risk of accidents on the pipelines crossing the zones of seismic activity, which is based on the need of correlation of probability of an accident in the earthquake-prone areas with the frequency of occurrence of strong damage causing earthquakes. In case of earthquake the probability of pipeline accident depends on the intensity of the seismic event. The frequency of occurrence of earthquakes of varying intensity in the areas can be determined by the terrain maps of general seismic zoning of Russian Federation territory (GSZ-97). The pipeline is divided into parts with different earthquake intensities in accordance with the general seismic zoning maps. The expected value of the length of the zones with possible accidents is determined by the GSZ-97maps. The conditional probability of accidents on the considered pipeline in the implementation of the events is also determined be the GSZ-97 maps. The estimation of the risk of accidents on the pipeline is provided by the map-based possible danger. The proposed approach is represented in the form of algorithm for determining the risk of pipeline accidents in seismic areas. Additionally, the algorithm is presented in matrix form. An example of the calculation of the risk on the main oil pipeline is considered. The frequency of accidents on the main oil pipeline in seismic areas is defined by accounting the intensity of pipeline accidents in the industry over the past 5 years and the frequency of earthquakes in pipeline zones. The proposed method of accident risk analysis can be used to assess the effectiveness of measures to reduce the individual, complex and social risks along the pipeline, as well as the reduction of factors of technical and environmental risk.