城镇燃气PE管道第三方挖掘施工损伤风险评价技术研究

发布时间：2018-05-07 07:32

本文选题：燃气PE管道 + 挖掘载荷　；参考：《西南石油大学》2017年硕士论文

【摘要】：随着我国对天然气等清洁能源的需求逐渐增大,城镇燃气事业进入蓬勃发展时期,城镇燃气管网的建设不断加快。在燃气管道工程中,由于聚乙烯(Polyethylene,以下简称PE)管的优良特性,已得到广泛的应用。但随着城市扩张步伐的加快,各类挖掘施工增多,挖掘施工导致的燃气PE管道泄漏事故频繁发生,因此需要提高对燃气PE管道第三方挖掘施工损伤的重视度。为解决对PE管道评价研究的相对欠缺,丰富城镇燃气管道风险评价的技术手段,本文针对城镇燃气PE管道第三方挖掘施工损伤开展了风险评价技术研究。主要研究内容如下:(1)分析管道所受外载荷,结合PE管道变形、应力、应变三个力学特征,建立力学模型;研究PE管道的力学损伤机理,从微观结构的角度分析管道破坏的原因;依据PE管道的三个力学特征,制定在挖掘载荷作用下的失效准则。(2)根据工程实际,运用ABAQUS有限元软件建立模型,从挖掘机斗齿直接作用于管道和未直接作用于管道两方面进行模拟,分析PE管道的动力响应、力学特征以及各参数变化对管道受力的影响。(3)引入易损性理论,结合致灾事件的危险性和受灾物体的易损性得到PE管道的失效概率。基于"人-机-环境-管理"系统建立危险因素体系,以专家评判为基础得到事件的危险概率;根据有限元软件的模拟结果和PE管道特性,确定易损函数,采用结构可靠度分析方法计算易损概率;结合危险概率与易损概率,最终得到管道的失效概率。(4)研究管道的泄漏模型与气体的扩散模型,确定发生各类事故后果的经验概率,建立喷射火、球火、闪火和蒸气云爆炸的计算模型,制定了热福射与冲击波超压的伤害破坏准则,并依据伤害破坏准则确定了事故后果的危害面积、死亡人数和经济损失。(5)引入ALARP原则,并结合风险矩阵,对失效概率和失效后果进行等级划分,确定燃气PE管道挖掘施工损伤的风险等级。运用本文建立的风险评价模型对实际案例进行评价,所得结果与实际情况相符,本文的研究成果能够为我国燃气管道的风险评价技术与完整性管理提供一定的技术支持。
[Abstract]:With the increasing demand for clean energy such as natural gas in China, the urban gas industry has entered a period of vigorous development, and the construction of urban gas pipeline network is accelerating. In the gas pipeline project, due to the excellent characteristics of polyethylene (Polyethylene, hereinafter referred to as PE) pipe, it has been widely used. With the increase of class excavation construction and the frequent occurrence of gas PE pipeline leakage caused by excavation construction, it is necessary to raise the attention to the third party mining damage of gas PE pipeline. In order to solve the relative lack of research on the evaluation of PE pipeline, the technology means to enrich the risk evaluation of urban gas pipeline is enriched. This paper aims at the third party of the urban gas pipeline of urban gas. The main research contents are as follows: (1) analyzing the external load of the pipe, combining the three mechanical characteristics of PE pipeline deformation, stress and strain, establishing the mechanical model, studying the mechanism of the mechanical damage of the PE pipe, analyzing the cause of the damage of the pipe from the angle of the microstructure, and according to the three mechanics of the PE pipe. Characteristics, the failure criterion under the action of excavating load is formulated. (2) according to the engineering practice, the ABAQUS finite element software is used to establish the model. The dynamic response of the PE pipe, the mechanical characteristics and the influence of the change of each parameter on the force of the pipe are analyzed. (3) the effect of the change of the parameters and the change of each parameter on the force of the pipe. Into the vulnerability theory, the failure probability of the PE pipeline is obtained by combining the hazard of disaster causing events and the vulnerability of the affected objects. Based on the "human machine environment management" system, the risk factor system is established, and the risk probability of the event is obtained based on the expert evaluation. The vulnerability function is determined according to the simulation results of the finite element software and the characteristics of the PE pipeline. The structural reliability analysis method is used to calculate the vulnerability probability, and the failure probability of the pipeline is finally obtained by combining the risk probability and the vulnerability probability. (4) to study the leakage model of the pipeline and the diffusion model of the gas, to determine the experience probability of all kinds of accidents, and to establish the calculation model of the explosion of the spray fire, the ball fire, the flash fire and the vapor cloud. The damage damage criterion of shock wave overpressure is determined, and the damage area, death toll and economic loss are determined according to the damage failure criterion. (5) introducing the ALARP principle, combining the risk matrix, grading the failure probability and failure consequence, determining the risk grade of the construction damage of the gas PE pipeline, and using the wind established in this paper. The risk evaluation model evaluates the actual case, and the results are in conformity with the actual situation. The research results of this paper can provide some technical support for the risk evaluation technology and integrity management of gas pipeline in our country.

【学位授予单位】：西南石油大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU996.7

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