【作者】 丁宇奇；

【导师】 刘巨保；

【作者基本信息】 东北石油大学 ， 油气田地面工程， 2014， 博士

【摘要】 立式拱顶储罐是原油储运过程中重要的储存设备，而储罐内超压产生原因、破坏压力计算与破坏条件判定和弱顶设计一直是储罐设计、安全运行中的关键技术问题。本文开展储罐内超压产生原因、储罐在不同超压形式下的破坏压力计算，以及储罐破坏条件与弱顶判定和弱顶设计的理论、数值分析方法研究，具有重要的学术价值和良好的工程应用前景。本着从简单到复杂的原则，开展如下研究工作。首先，以立式拱顶储罐为研究对象，对储罐内两种动态升压方式可燃气体燃烧和爆炸进行了分析。采用定容燃烧法对储罐内可燃气体燃烧升压几何分析、燃烧温度和燃烧速度进行计算，得到了储罐内由于可燃气体燃烧引起超压的计算方法；通过对TNT爆炸影响的因素分析，建立了由于可燃气体爆炸导致储罐超压的TNT当量计算法，考虑爆炸冲击波峰值压力在储罐内的反射问题，结合爆炸冲击波的几何分析，得到了储罐内可燃气体爆炸的峰值超压计算方法。其次，针对储罐静压作用下的超压问题，分析了罐顶两种破坏形式，抗压环屈服导致的局部失稳破坏和由于顶壁连接焊缝强度不足导致的强度破坏。对拱顶储罐抗压环截面受力进行了分析，分析了储罐设计标准中顶壁连接处破坏压力与抗压环截面的计算方法。以危险截面的平均应力达到材料的屈服强度，建立了储罐的强度破坏条件。并通过对储罐顶壁连接处的有力矩理论分析，建立了考虑弯矩的储罐顶壁连接处破坏压力计算公式。其三，采用壳单元、实体单元、梁单元对罐顶肋条、连接焊缝、包边角钢、顶板、底板、壁板、地基等结构进行离散，采用接触单元模拟顶板与肋条、底板与地基的单向接触摩擦问题，建立了储罐空间数值计算模型，通过对不同容积储罐在空罐、半罐和满罐的有限元计算分析，得到了罐顶与罐底的破坏压力。按照结构相似性，制造了实验储罐，通过储罐超压破坏试验，对罐顶两种破坏方式及破坏压力计算公式与储罐破坏条件进行了验证。其四，分析了储罐内由于可燃气体燃烧和爆炸引起的储罐内两种动态超压过程，在燃烧超压中，储罐内各位置处的压力仅与燃烧时间有关；在爆炸超压中，储罐内各位置处的压力与距爆炸点位置和时间均有关。通过建立储罐动力学计算模型，给出了储罐在不同动压下的破坏条件，对典型容积拱顶储罐在两种超压模式下，罐顶与罐底的破坏压力进行了计算。最后，通过对不同容积拱顶储罐在空罐、半罐和满罐下各种受力状态的力学分析，结合储罐顶壁连接处与底壁连接处破坏条件与破坏压力，建立了拱顶储罐弱顶评价条件，并建议储罐为弱顶结构时k empty1.5(空罐)、 k full2.5(满罐)。对不同容积拱顶储罐在不同超压形式下的弱顶性能进行了计算，得到了储罐在不同液位下的弱顶性能变化规律。针对影响储罐弱顶性能的主要影响因素，对各容积储罐在不同工况的弱顶性能进行了分析，提出了不同容积储罐的弱顶设计方法。通过改变储罐单个设计参数或多个设计参数，使其满足弱顶性能，设计出了满足弱顶要求的拱顶储罐。本文研究成果可作为储罐事故发生原因、预防和灾难救援，火灾控制以及储罐弱顶设计提供重要的理论基础与计算方法。更多还原

【Abstract】 Vertical dome roof tank is important storage equipment in the process of storage andtransportation of crude oil, and the tank overpressure mechanism, failure stress calculation,destruction condition judgment and weak roof design have been the key technical problemsof the tank design and safe operation. This paper carried out the mechanism of tankoverpressure, tank failure stress calculation in different forms of overpressure, the judgmentof storage tank damage and weak roof judgment and a weak roof design theory as well asnumerical analysis method of study, which have important academic value and goodprospect of engineering application. Based on the principle of from simple to complex,carry out the following research work.First of all, take vertical dome roof tank as the research object, two kinds of dynamicpressure rise inside the tank, combustible gas burning and explosion are analyzed. Using theconstant volume combustion method, combustible gas in the tank booster geometricanalysis, combustion temperature and combustion rate has been calculated, got thecalculation method of storage tank caused by combustible gas explosion; By TNT explosiveimpact on the factor analysis, established the TNT equivalent calculation method caused bycombustible gas explosion overpressure, considering the blast shock wave peak pressure inthe storage tank reflection, according to the geometrical analysis of the explosion shockwave, got to the overpressure peak value calculation method of combustible gas explosion.Secondly, in view of the storage tank overpressure problem under the action of staticpressure, analyzed two damage forms of the tank roof, local buckling failure caused bycompression ring yield and strength damage caused by the hanging wall connection weldstrength insufficient. The vault tank compression ring cross-section stress is analyzed,analyzed the calculation method of roof joint damage pressure and compressive ringcross-section in tank design standard. Established the tank damage conditions by makingthe average stress of dangerous section to achieve material yield strength. Through torquetheoretical analysis of storage tank roof joint, established tank roof joint damage stresscalculation formula considering bending.Thirdly, the shell element and solid element and beam element are adopted to roof rib,weld joint, edge Angle, roof, bottom plate, shell, foundation etc to discrete the structure,contact elements are adopted to simulate the roof and rib, bottom plate and the foundationof one-way contact friction problem, storage space numerical calculation model isestablished, based on different capacities of the storage tank under the empty, half loadedand full working conditions finite element analysis, the destruction of the roof and bottom pressure are obtained. Manufactured experimental tank using structure similarity principle,by the destruction test on the tank overpressure, two failure modes and failure pressurecalculation formulas and tank damage conditions are verified.Fourthly, the paper analyzed the two kinds of dynamic process of overpressure ofstorage tank caused by combustible gas combustion and explosion in storage tank, incombustion overpressure, pressure on different location is only related to the burning time;in explosion overpressure, pressure on different location is associated with both distancefrom blast point position and time. By establishing a dynamic computational model ofstorage tank, given the destruction of the storage tank under different pressure conditions,calculated the failure pressure of typical capacities storage tank under two kinds ofoverpressure, the destruction of the roof and bottom.Finally, based on different capacities of the dome roof storage tank in the empty, halfloaded and full working condition tank under various stress mechanics analysis, combiningof tank roof joint and the bottom joint damage conditions and destruction pressure,established the evaluation condition of a dome roof storage tank, and recommended thatwhen the storage tanks is with weak roof structure, k empty1.5(empty tank),k full2.5(full tank). Based on calculation on dome roof storage tank of different capacitiesunder different forms of overpressure, got the weak roof performance variation underdifferent liquid levels. In terms of the main influencing factors of the tank weak roofperformance, analyzed the weak roof performance of different capacities under differentworking conditions, and put forward weak roof design methods of the tank in differentcapacities. By changing a single or some parameters of storage tank to satisfy its weak roofperformance, to design a tank that satisfies the requirement of weak roof.This article research results can be used as tank disaster relief, prevention and rescue,fire control, and storage tank design, providing important theoretical basis and numericalcalculation method.更多还原