【作者】 杨涛；

【导师】 张文福；

【作者基本信息】 大庆石油学院 ， 油气田防灾减灾工程及防护工程， 2010， 硕士

【摘要】 液化天然气(Liquefied Natural Gas,以下简称LNG)具有便于运输和储存、使用安全的特点,在过去的几十年中,世界LNG消费量大幅度增加,各国均将液化天然气作为一种低排放的清洁燃料加以推广。LNG储罐是存储、使用LNG过程中所用到的重要设备。目前国外对LNG储罐已有不少研究成果并且很多成果已应用到工程实际中,但是针对LNG储罐的抗风和抗震研究相对欠缺,结构设计人员也迫切需要了解LNG储罐在承受各种动力荷载内力及变性规律。因此,开展LNG储罐的抗风和抗震的力学性能研究具有重要的意义。本文的主要研究工作集中于两种LNG储罐的自振特性、风致屈曲和地震响应分析。主要内容包括:1.LNG储罐有限元模型的建立采用有限元软件ANSYS建立有限元模型,利用ANSYS单元库中提供的Shell63、Shell91单元分别建立混凝土LNG储罐模型和夹心LNG储罐模型,并通过模型的振动特性验证其合理性,验证标准为本文建立的Solid45有限元模型。2.LNG储罐的自振特性建立两种LNG储罐空罐状态下的全罐、半罐、1/4罐模型,分别对其进行模态分析,得到六种有限元模型的各阶频率和振型,分析两种简化的有限元模型同整体模型的异同。3.LNG储罐风致屈曲分析比较国内外几种圆柱形结构物的周向及竖向风压分布,并提出适合本文的风压分布形式。将上述风压以面荷载的形式施加到储罐上,得到两种LNG储罐的临界屈曲风速。4.LNG储罐地震响应分析按照我国《建筑抗震设计规范》要求,选取三种地震波对两种储罐进行单向水平地震波作用下的响应分析,记录储罐特殊位置点的时程曲线,得到LNG储罐在三种地震波作用下的位移、加速度、应力分布规律。更多还原

【Abstract】 Liquefied Natural Gas (hereinafter referred to as LNG) has the features of convenient transport and storage, safety use. In the past few decades, the world LNG consumption has a substantial increase, all countries put LNG as a clean fuel with low emissions to promote them. LNG tank is the important equipment in storage, use of LNG tank.There has been a lot of research results abroad and many of them have been applied to engineering practice, but lack of wind and seismic studies for the LNG tank. Structural designers also have an urgent need for internal force and deformation law of LNG tanks under a variety of dynamic loads.Therefore, shoud have an in-depth study of LNG tank resist wind and seismic.This study focused on vibration characteristics, wind-induced buckling and seismic response analysis about two kinds of LNG tanks. The main contents include:1. Verfication for element model of LNG tankUsing finite element software ANSYS creat finite element model, in which shell63, shell91 element models provided by ANSYS cell libraries were used to creat concrete LNG tank and sandwich LNG tank model. Verifing its legitimacy through the vibration characteristics of the model, based on the results of Solid45 finite element model provided by ANSYS.2. The vibration characteristics of LNG tankCreating the whole tank, half tank, 1 / 4 tank model of empty state of two types of LNG tanks, first sixth orders of natural frequency and vibration mode are obtained through mode analysis for finite element model.Analysis the similarities and differences of two simplified finite element model with the whole tank model.3. Wind-induced buckling analysis of LNG tankComparison of several circumferential and vertical wind pressure distribution of cylindrical structures abroad to propose suitable form of wind pressure distribution for this article, and put this wind pressure in the form of surface loads applied to the storage tank, to get critical buckling velocity of this two kinds LNG tank.4. Seismic response analysis of LNG tankAccording to requirements of Chinese "code of building seismic design", analyze this two kinds of tanks of unidirectional level seismic response analysis under the action of selected three kinds of seismic waves, recording the time-history curve for special points of LNG tank. Obtaining LNG tank’s displacement, acceleration, stress distribution law under the action of selected three kinds of seismic waves.更多还原