圆筒型FPSO阻尼板结构强度计算方法研究

阻尼板作为增加圆筒型FPSO附连水质量和黏性阻尼的关键装置,可有效降低垂荡和横摇运动.阻尼板通常为与柱型筒体相连的悬臂梁式箱型结构,阻尼板及其与筒体连接区域处的结构设计及强度校核是圆筒型FPSO结构设计的关键.以阻尼板处最大压力及最大阻尼力作为目标设计载荷,采用子模型法校核其结构强度,以总强度分析得到的变形作为子模型边界条件,采用Morison法模拟黏性阻尼载荷,对阻尼板结构强度进行校核分析,为阻尼板的结构设计提供依据和指导.     

仿生机器鱼胸尾鳍协同推进的水动力学分析

利用CFD技术对仿箱鲀科胸尾鳍协同推进机器鱼的水动力学特性进行分析,将整个机器鱼放入流场,对其胸鳍推进模式、尾鳍推进模式和胸尾鳍协同推进模式的水动力学特性进行对比,得出不同模式下机器鱼水动力学的变化规律。分析得出,在压力变化云图中,胸尾鳍协同推进产生的压力变化最为复杂;在速度涡量变化图中,胸尾鳍协同推进产生最为复杂的涡量变化,胸鳍运动产生的涡会逐渐脱落向后移动,与尾鳍产生的涡互相作用,增加尾鳍的推力,从而证明胸尾鳍协同推进模式是一种高效的推进机制。     

浅谈预应力仓库张拉工艺

着重介绍能够承载重型集卡行走的二楼仓库层面结构,井字形主次梁内预埋波纹穿管,待砼浇注后采用预应力张拉钢绞筋法施工工艺。通过预应力后张拉使得楼层承载力得以极大提高,并使主次梁截面明显缩小。达到确保结构稳定可靠、并有效节约工程投资的目的。     

船舶制造企业数据中台建设研究

随着船舶建造企业信息化建设的不断推进,企业内部信息系统间也开始产生数据流通不畅等问题。为此,本文深入分析了船舶建造企业当前数据问题产生的根源,以提高船舶建造企业自身生产经营效率为目的,针对数据互联互通需求,探索讨论了适合船舶建造企业的数据中台建设路径和总体架构。     

碳纤维缠绕复合材料在潜水外压容器上的应用

在铝合金圆筒体以外以浸渍树脂碳纤维进行缠绕复合增强，可大幅度提高筒体的耐静水外压能力，整体缠绕的全复合材料筒体，在耐静水外压能力及减轻自身重量方面也获得了明显的效果。此外，在铝合金细长圆管的外壁复合缠绕纤维，能有效地提高圆管对轴向压载荷的抗失稳与抗屈曲破坏能力。     

Research on the Influence of Vertical Deformation of Bridge on the Track RegularityEI北大核心

Research purposes: The vertical deformation of high-speed railway (HSR) bridge will cause the track irregularity, which threatens the safe and efficient operation of the HSR. Taking the 32 m simple supported beam bridge as the research object, based on the existing mapping analytical model for bridge vertical deformation and rail geometry, the influence of the track regularity of the CRTS Ⅰ slab ballastless track structure caused by the key parameters such as the bridge vertical deformation amplitude, the hanging length of the beam end and the vertical stiffness of mortar layer were studied, and the corresponding measures to control the rail deformation were proposed, to provide theoretical reference for comprehensive treatment of rail deformation of HSR bridge. Research conclusions:(1) The pier settlement, the vertical rotation of the beam end and the beam fault will cause the rail to follow the beam deformation, and "up-warping" of the rail on the vertical deformation boundary will appear. (2) The rail deformation is directly proportional to the vertical deformation amplitude of the bridge and the key to control the rail deformation is to reduce the vertical deformation of the bridge. (3) The rail deformation can be controlled by reducing the hanging length of beam and vertical stiffness of mortar layer. (4) The research results can provide a theoretical reference for controlling the vertical rail deformation of high-speed railway bridges. © 2018, Editorial Department of Journal of Railway Engineering Society. All right reserved.     

单线特长铁路隧道CRTSI型双块式无砟轨道施工技术

双线隧道内整体道床的施工可以通过另一条线运输材料,布设机具、行车调度都不是难点技术,但在单线隧道内,施工工序的安排受到很大影响,材料机具只能摆放在避车洞内或水沟电缆槽盖板上,不但影响了作业空间,而且对盖板破坏较为严重。托架式工具轨法所采用的材料机具简单,在经过工艺改进后,可以有效解决空间狭小的问题;通过拉日铁路盆因拉隧道成功实践,可供类似隧道整体道床施工参考。     

Online channel strategies under different offline channel power structures for the Belt and Road of China

ABSTRACT

This paper explores the online channel strategies adopted by Chinese manufacturers with regard to the Belt and Road. It also investigates the effect of offline channel power structures and maritime transportation costs on online channel mode selection and pricing strategies. The offline channel power structures are classified into three types, namely, Chinese manufacturer Stackelberg (MS) structure, vertical Nash (VN) structure, and foreign retailer Stackelberg (RS) structure. Furthermore, a game model is developed among the Chinese manufacturer, foreign retailer, and cross-border e-tailer to investigate the interactions among offline channel power structures, maritime transportation costs, and Chinese manufacturers’ online channel mode selection. The results show that Chinese manufacturers’ preferences for the online agency selling mode increases correspondingly with the decrease in their market position and bargaining power. Moreover, foreign retailers can obtain higher profits in the online agency selling mode under the VN structure. However, the level of profit for foreign retailers depends on the intensity of their competition with cross-border e-tailers under the MS and RS structures. Finally, consumers in countries along the Belt and Road can obtain a higher surplus in the online agency selling mode under all of the structures.     

高速铁路路桥过渡段地基沉降测试与预测方法研究

以津秦客运专线路桥过渡段路基沉降测试为例,利用BP神经网络方法和灰色系统法研究了路桥过渡段沉降预测问题。计算实例表明,神经网络法和灰色系统法短期沉降预测结果比较准确,简便易行,因而具有广泛的工程实用价值和应用前景。     

轮轨润滑降低重载货车轮轨磨耗作用的研究

轮轨润滑是重载铁路减轻轮轨磨耗及损伤的有效措施之一。基于多体动力学理论,建立了配装不同类型转向架的C80B型重载车辆动力学分析模型,利用多点接触轮轨模型和轮轨接触摩擦功进行磨耗评价。计算得出了不同曲线工况下,轮轨润滑对交叉支撑转向架和径向转向架轮轨磨耗的作用规律。