| China is a frequent geological disaster-prone country,as an important part of the lifeline inevitably,pipeline passes through typical geological disaster areas,such as strong earthquake areas,active fault zones.These natural disasters can cause pipeline prone to excessive deformation and failure,resulting in significant economic losses and casualties.This paper focuses on deformation and strain of buried pipeline crossing fault,finite element software is used to calculate the reliability of buried pipeline in different conditions.Based on it,the main aspects of the work can be concluded as following several points.First of all,the different strain-based design criteria are compared and analyzed.The calculation and basic theory of reliability analysis are studied,and the reliability analysis method is determined.The calculation of ultimate strain of the pipeline is studied,and the specific calculation formula is obtained.Combined of the reliability theory and strain criterion,the reliability model of buried pipeline strain is established.Secondly,the finite element software is used to analyze and study the established finite element model for pipe-soil interaction.The influence of fault parameters and geometrical parameters on the axial maximum strain and axial strain distribution of buried pipelines crossing fault are calculated and analyzed.It is discovered that when the fault displacement reaches a certain value,the axial compression strain will increase sharply due to the focus of strain and the appearance of wrinkle,and the phenomenon of buckling will happen on the compression side firstly.The reliability of the pipeline under different conditions is also calculated in this paper.The influence of the variation coefficient of random variables and the selected types are analyzed on the influence on the result of reliability calculation.Research on the distribution along the pipeline are also carried.In general,the reliability in the position where the maximum axial strain occurs will be lowest,and it is most easily damaged in the position.In the reliability analysis,the reduce of random variables will make the calculated reliability to a certain extent increasing,and the influence of geological variables on strain reliability of pipeline is greater.In order to ensure safety,it is needed to take full account of the parameters related to pipeline and the fault,especially the fault related parameters to obtain the more safe and reliable results.The programming language Visual Basic is used compile the interactive software which is based on finite element software to calculate.The software helps increase the efficiency of large amount of computation,it also provides great convenience for the engineering technicians who are unfamiliar with finite element software. |
PDF Full Text Request