【作者】 韩东颖；

【导师】 周国强；

【作者基本信息】 大庆石油学院 ， 安全技术及工程， 2004， 硕士

【摘要】 石油井架是石油装备的重要组成部分。多年来，井架倒塌事故时有发生，只在线弹性范围内评价井架的承载性能已经不能完全满足现场井架作业的需要，因而合理地预报出井架的极限承载力，已成为石油井架安全评定理论所研究的重要内容。 鉴于工程上最常用的方法是通过测试现场井架应力，以线性外推法确定井架的安全承载力，因而本文提出了以测试杆件的应力为参照修正井架数值模型从而预测井架极限承载力的方法，这一方法的提出实现了安全评定理论与极限承载预测在算法上的统一和在理论上的连续性。 本文首先应用有限元法分析了井架结构的几何非线性和材料非线性，并借助大型工程辅助分析软件ANSYS建立了无初始缺陷井架数值模型，分析了在设计承载范围内，几何非线性对井架承载各参数的影响；并对数值模型井架进行了几何非线性和双重非线性极限承载性能分析，得出预测A形井架的极限承载力必须考虑双重非线性的影响。 本文将理论分析与测试数据相结合，室内试验与室外试验相融合，采用64通道实时并行大容量静动态测试系统，基于PCI总线DAQ系列数据采集板，LabVIEW数据采集软件，DASYLab数据分析平台对室内实验室模型井架和现场在用井架进行数据采集及分析，为准确预测井架极限承载力提供了准确充足的数据。 最后，基于以上理论分析及测试数据，本文提出了以参考应力法修正无初始缺陷井架数值模型从而预测含损伤缺陷井架极限承载力的方法，这种方法虽在理论上能达到精确的程度，但必须修正数值模型井架每一单元的应力，工作量大，因而本文实际做法以测试杆件的应力为参照来预测井架的极限承载力。实验室模型井架预测结果与试验值相差仅为5％，从而验证这一做法的可行性。更多还原

【Abstract】 Oil derrick is an important part of oil equipment. For many years, some accidents of derrick collapse have happened occasionally, only according to the elastic theory to evaluate can’t meet the need of oil field derrick work fully. Therefore, forecasting the ultimate bearing capacity properly has become an urgent content of safety evaluation theory.As the most frequently employed method is to determine the load resisting capacity by the method of the linearity extrapolation from the measured data about stress, thus this paper present the ultimate bearing capacity method based on the measured stress of derrick members to modify the computer numerical model, which realized the unification on algorithmic analysis and continuity on theory between safety evaluation and ultimate bearing capacity forecasting.This paper firstly analyzed the geometric and material nonlinearity according to FEM method. After it, it established the numerical model of perfect derrick by using huge engineering auxiliary software-ANSYS, and analyzed the influence of geometric nonlinearity on the parameters of derrick; In addition, this part discussed the geometric and double nonlinear ultimate bearing capacity aiming at numerical model and concluded that double nonlinearity must be considered if you want to acquire the ultimate bearing capacity of A-shaped mast.This thesis combined not only the theory analysis of derrick structure and measured data but also test in Lab and test in oil field. Further more, this research has adopt mass parallel real-time test system with 64 channels, DAQ data acquisition panel with PCI wire, Labview software and DASYlab analysis platform. We gathered and analyzed data of Lab model and derrick in oil field and then offered enough and accurate data for forecasting ultimate bearing capacity.Finally, according to the research above, the author presented the method, with which we can forecast the ultimate bearing capacity of derrick with defeats and defacements by modifying the perfect numerical derrick model with the method of taking measured stress as reference. This method could achieve excellent solution, but we must modify each element of FEM numerical model and then the amount of work is very large. Therefore practically the author took the measured stress of derrick members as reference to infer the ultimate bearing capacity. The relative error is only 5% between the forecasting result of Lab model and the result of collapsing test, which also proved that it is a feasible.更多还原