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131.
132.
以中石化仪征15万m3大型浮顶储油罐工程为例,研究了砂石褥垫层对大型储油罐基础的差异沉降的影响。根据行业标准《建筑地基处理技术规范》(JGJ79—2012)沉降公式计算以及有限元模拟计算,并结合现场实测数据,验证了有限元模拟分析的可行性,在此基础上进行了环墙内砂石垫层厚度及长度对差异沉降影响的扩展研究,为以后的类似工程项目设计施工提供了借鉴。 相似文献
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134.
Method of checking for jack-up elevated performance including leg structure strength, fixation system or jacking system bearing capacity, pre-load requirements, spud can bearing capacity and overturning stability is suggested in this paper. As an example, a jack-up with truss legs is analyzed by finite element analysis method. This paper may be helpful to the rig owners, operators and designers. 相似文献
135.
南海中央海盆岩石圈纵向演化模拟 总被引:1,自引:0,他引:1
基于南海海盆的地质构造历史、地球物理和构造应力场资料建立准三维有限元模型,对南海中央海盆进行岩石圈纵向演化动力学模拟.本文采用弹塑性各向同性连续岩石介质模型,充分考虑拉伸速率、拉伸位移以及模型参数对模拟结果的影响,共建立了3个模型进行比较.从数值模拟结果可以看出中央海盆在被动拉张的地质构造背景下是单向生长的,动态模拟出南海中央海盆在形成过程中的陆缘裂离、海底扩张两个阶段的岩石圈纵向演化过程,并且分析了两个阶段岩石圈的动力学性质.提出水平的被动拉张力是南海岩石圈纵向演化前两个阶段形成的主要因素,并且在这两个阶段中,岩石圈的纵向演化时间主要集中在海底扩张阶段. 相似文献
136.
137.
To address the limitations of manually selecting aids to navigation (AtNs) on charts, a method for automatically selecting AtNs based on their spatial influence domains (SIDs) is proposed. First, the associations between the spatial attributes of an AtN are analyzed. Second, an SID of the AtN is defined, and a model of the SID is constructed based on the associations between the spatial attributes. Third, the importance of the location of the AtN is weighted based on the SID model. Fourth, an algorithm to automatically select AtNs based on the maximum coverage of the SIDS of preselected AtNs is developed. Finally, several AtNs are selected automatically using the algorithm. The experimental results demonstrate that (1) the proposed method can automatically select AtNs and the results comply with the requirements; (2) the automatic selection can eliminate the human-induced errors or the inconsistent results of manual selections from different operators; and (3) the efficiency of the proposed method is higher than that of current manual methods. 相似文献
138.
A time-domain simulation method based on potential flow model has been developed to investigate the berthing problem between two floating bodies in wave. The boundary value problem is formulated with respect to an earth-fixed coordinate system because the relative positions of the two vessels continuously change during the berthing operation. The classical finite element method is used to solve the Laplace equation in the fluid domain with moving boundary. The linearized free-surface boundary conditions are integrated in time by applying 4th-order Adams–Bashforth–Moulton method. A simple re-mesh algorithm with local and global mesh systems is introduced to update mesh by considering large horizontal movement of the berthing vessel. The developed numerical method is used to investigate the berthing problem between a FPSO and shuttle tanker in waves. The focus is on the wave-induced motion response during the berthing process. The characteristics of the motion responses in berthing operation are examined with various wave frequencies, berthing speeds and wave headings. 相似文献
139.
The interaction of a solitary wave with an array of surface-piercing vertical circular cylinders is investigated numerically. The wave motion is modeled by a set of generalized Boussinesq equations. The governing equations are discretized using a finite element method. The numerical model is validated against the experimental data of solitary wave reflection from a vertical wall and solitary wave scattering by a vertical circular cylinder respectively. The predicted wave surface elevation and the wave forces on the cylinder agree well with the experimental data. The numerical model is then employed to study solitary wave scattering by arrays of two circular cylinders and four circular cylinders respectively. The effect of wave direction on the wave forces and the wave runup on the cylinders is quantified. 相似文献
140.
渤海油田中深层轻质油气流富集,原油密度小,气油比高,普遍处于气液同存的的交错相态。由于轻质油、气层荧光、气测等录井特征相似,加之部分井眼条件差,测井资料不完善,造成流体识别难度大。对目前常用的气测录井系统开展轻质油气藏流体性质评价研究发现,基于常规气测组分(C1—C5)的3H组合模型呈现一定的规律性,但与传统解释模型存在差异,结合星型图流体相分析法,可有效识别渤海油田PL7区块凝析气与轻质油,流体界面明显。对于FLAIR气测录井系统,针对测量组分(C1—C8)引入能够敏感反映油气丰度变化的气指数、油指数和水指数3个流体指数,依据这3个流体指数的纵向组合形态和变化趋势,可准确识别油气性质,对渤海油田轻质油气藏的流体评价优势明显。该研究促进了所在区块油气分布格局和储量的落实,在其他钻遇轻质油气流的区块具有较高的推广应用价值。 相似文献