断层地表同震位错的平均位移估计方法

Estimation of average displacement of fault surface co-seismic dislocations

根据管道性能设计的理念,现行管道抗震设计规范规定现行输油气管道重要区段和一般区段的设防断层位移分别为预测的最大位移值和平均位移值,目前的断层位移估计方法一般给出的只是断层未来一百年的最大位移值,而不能给出平均位移值。针对此问题,本文综合国内外发震断层在地表的同震位错分布调查结果,总结分析了断层同震位错沿断层地表破裂走向的分布形态特点,并通过对实际震例中不同计算方法得到的平均位移进行对比分析,得到了断层的平均同震位错量与断层最大同震位错量的比值关系。基于国内外地震断层位移的大量数据,考虑一定的安全系数,本文建议采用预测断层最大位移值的2/3作为一般区段输油气管道的设防断层位移。

According to the concept of pipeline performance design,the current seismic code for oil and gas pipelines stipulates that the displacement of fortified faults in important sections and general sections are the predicted maximum displacement and average displacement,respectively.However,at present,the fault displacement estimation method generally gives only the maximum displacement of the fault in the next 100 years,but not the average displacement.Therefore,based on the investigation results of co-seismic dislocation distribution of seismogenic faults on the surface at home and abroad,the distribution characteristics of co-seismic dislocations along the surface fracture trend of the fault are summarized and analyzed in this paper.And then the ratio of the average co-seismic dislocation of the fault to the maximum co-seismic dislocation of the fault is summarized by the statistical comparison and analysis of the average displacement obtained by different calculation methods in the actual earthquake cases.Anyway,based on a large number of data of seismic fault displacement at home and abroad,considering a certain safety factor,this paper suggests that 2/3 of the maximum displacement of the predicted fault should be used as the fortification displacement of the oil and gas pipeline in general sections.