NUMERICAL SIMULATION OF OIL AND GAS PIPELINE VULNERABILITY EVALUATION INDEXES UNDER EFFECT OF LANDSLIDE

摘要

The integrity of oil and gas pipelines is seriously impacted by landslides in tough terrain in westemChina. The quantitative e-vahiation technology is an effective method for pipelines risk management under the threat of geohazard. In order to establish the pipeline vulnerability evaluation indexes under effect of landslide, the finite element method is adopted to simulate landslide movement, pipeline mechanical behavior and soil-pipe interaction by changing geometrical sizes and mechanical characteristics of them, such as the landslide area, landslide thickness, material composition of landslide, movement type of landslide, pipehne length in landslide, diameter, wall thickness and strength of pipelines. The regularity for change of stresses and deformations of pipeline subjected to landslide can be obtained by means of numerical simulation. The results show that the geometrical sizes of landslide and the pipeline length in landslide have great effect on pipeline vulnerability, and the effect increases with increasing of the above indexes; the wall thickness and strength of pipeline have less effect on pipehne vulnerability and the effect can be ignored. In the end, the weights and scores of every vulnerability evaluation index can be given on the basis of the above conclusion.