柔性栈桥新概念设计研究

为提高铁路轮渡栈桥对船型的适应性,提出一种一端固定连接岸上,另一端能够上下、左右移动,从而连接来船不同部位,便于车辆进出船舱的柔性或活动船岸连接栈桥构造方案.给出这种新型柔性栈桥的基本构造和主要构件组装特征,说明了其工作原理.进而推导出栈桥活动端的横移距离、偏转角度、纵桁外伸长度等关键设计参数的函数关系.研究结果表明,这种新型柔性栈桥具有可行性和实用性.     

海洋平台栈桥管道应力分析的模拟方法

栈桥是连接海上油气田两个或多个平台间油气水管线、电控线缆和人员通行的通道.平台间在风、波浪、船舶靠泊等荷载作用下会发生相对运动,通过栈桥的管道会承受平台间相对运动产生的位移荷载,管道应力水平是否满足规范要求在应力分析中需要重点考虑.应用CAESAR II软件,结合旅大27-2/32-2油田开发项目栈桥管道柔性计算实例,介绍了栈桥管道应力分析的模拟方法,并根据计算结果对管道布置提出建议和进行优化,为以后栈桥管道的设计提供计算方法和参考.     

琼州海峡铁路轮渡港口工程中汽车和旅客活动栈桥液压系统设计

介绍新建的琼州海峡铁路轮渡工程和汽车和旅客活动栈桥液压系统设计方案及其实施后的效果。     

船载登陆栈桥系统卸载时的横摇响应计算

在无码头的情况下,利用集装箱船改装后的渡海输送登陆栈桥系统,具有装卸载不依赖吊装设备的优点,使登陆栈桥系统能够迅速展开和拼装.在缺乏港口屏蔽的海浪环境中,登陆栈桥系统进行卸载,必须考虑波浪对船的作用和登陆栈桥系统与船的相互作用.利用浮基多体系统动力学方法,考虑海况、船型和登陆栈桥系统在船上运动参数等因素,计算了各工况下的横摇运动响应,进而给出了登陆栈桥系统安全卸载的操作要求,对集装箱船改装可行性提供了理论支持.     

海上风电运维船小型化波浪补偿登乘栈桥设计

针对海上风电机组运维需求,设计海上风电运维船的小型化波浪补偿登乘栈桥。进行登乘栈桥的总体设计、力学分析和软件设计,并对登乘栈桥的三维模型进行有限元仿真。仿真结果表明,所进行的设计可满足海上风电运维船的小型化和轻量化要求,保证人员与物料的安全和作业环境的稳定。     

铁路轮渡技术现状与研究动态

铁路轮渡运输是铁路在水上延伸运输的一种传统模式.回顾这种运输模式发展的历史进程,介绍了铁路轮渡工程中一些关键技术的现状,分析了现实需求与现有技术的差异.在此基础上,提出需要进一步深入研究的技术问题,指出铁路轮渡发展的关键是研究设计出更加方便、灵活且具有通用性的船岸连接设备,未来发展的趋势是在全球范围内形成水陆一体化综合运输系统.     

谈烟大铁路轮渡工程汽车和旅客栈桥设计

文中介绍烟大铁路轮渡工程汽车和旅客栈桥总体设计方案,及方案实施后的效果,以供借鉴。     

粤海铁路轮渡码头汽车活动栈桥支座病害原因分析及对策

基于对粤海铁路南、北港汽车活动栈桥投入使用后的长期观察,描述了栈桥支座发生病害的特征经过,并通过对栈桥支座病害原因分析,提出了一些改善栈桥性能的建议和措施.     

野战移动栈桥的设计思路

去年7月,"野战移动栈桥"参与了"成功8号"渡海登岛作战演习,架设跨度30米临时栈桥供部队重装备滚装,仅耗时21分钟就圆满完成了任务,创造了国际上单车架设栈桥长度的新纪录,得到全军军交运输工作会议的充分肯定.     

铁路渡轮装卸过程模拟方法初探

为了模拟一种采用新型柔性连接轨道的铁路渡轮的装卸过程,推导了柔性轨道在各种弯曲状态下的几何表达式,设计了机车、车辆运动控制算法和装卸作业流程图。以Matlab软件为平台,开发了铁路渡轮装卸过程模拟程序,能够动态地模拟这种基于柔性轨道的新型装卸设备的装卸作业过程。模拟结果还可以同时给出装卸作业需要的总时间,便于与现有系统进行对比分析。     

单向格栅软体排顺水沉排受力特性研究

单向格栅软体排是一种以单向格栅为受力构件,自下而上由反滤土工布、单向格栅和混凝土压载块3部分组成的新型软体排结构。以长江中下游护底工程为应用场景,利用有限元法模拟单向格栅软体排在顺水沉排施工条件下的受力特性,发现随着相对移船位移、水深、水流流速和压载质量的增大,单向格栅软体排体的最大应力逐渐增大;随着水流方向与沉排方向夹角的增大,单向格栅软体排所承受的最大应力逐渐减小。在各种顺水沉排条件下,铺排船翻板下端处的单向格栅软体排受力最明显,且软体排承受的最大应力位于翻板下端的软体排宽度方向上距离两侧边缘约1 m的位置,软体排中间部位受力较小。结果表明：单向格栅软体排所承受的最大应力远低于其抗拉强度,该新型软体排结构在长江中下游护底工程中具有较好的适应性,相对于传统的加筋软体排,单向格栅软体排可减少20%以上的排布成本。     

受损伤的预应力混凝土T梁无损检测分析

结合河南省某高速公路特大桥施工过程中受损伤的预应力混凝土T梁的无损检测,通过超声波对测方式普查T梁底部和两端腹板底部混凝土,并结合混凝土表面裂缝分布形态和裂缝大小,确定了混凝土内部缺陷状况;采用回弹法确定了混凝土表面强度大小及其分布的均匀性。为同类结构的无损检测提供参考。     

缓波型柔性立管构型优化及敏感性分析

针对缓波型柔性立管存在的波型较陡和浮子段张力较大的问题,对其进行优化,将单波构型优化为双波构型,运用集中质量法对改进前后的2种结构形式进行分析,确认双波构型在静力和动力响应下的张力及弯曲特性更优。在此基础上,对双波型柔性立管进行敏感性分析。在静力状态下,悬挂点和第2段浮子段末端对浮子段间隔和浮子段长度敏感;在动力响应下,悬挂段到第1段浮子段的张力变化和最小弯曲半径对浮子段间隔和大悬挂角非常敏感。研究得到的敏感性参数结论可作为缓波型柔性立管总体布置设计的参考。为提升缓波型柔性立管的性能,可合理增加浮子段与浮子段的间隔和悬挂角,但同时要满足规范的要求,避免关键部位动力响应过大。     

柔性立管整体分析(英文)

The mechanical performance of a flexible riser is more outstanding than other risers in violent environmental conditions. Based on the lumped mass method, a steep wave flexible riser configuration attached to a Floating Production Storage and Offloading (FPSO) has been applied to a global analysis in order to acquire the static and dynamic behavior of the flexible riser. The riser was divided into a series of straight massless line segments with a node at each end. Only the axial and torsional properties of the line were modeled, while the mass, weight, and buoyancy were all lumped to the nodes. Four different buoyancy module lengths have been made to demonstrate the importance of mode selection, so as to confirm the optimum buoyancy module length. The results in the sensitivity study show that the flexible riser is not very sensitive to the ocean current, and the buoyancy module can reduce the Von Mises stress and improve the mechanical performance of the flexible riser. Shorter buoyancy module length can reduce the riser effective tension in a specific range of the buoyancy module length when other parameters are constant, but it can also increase the maximum curvature of the riser. As a result, all kinds of the riser performances should be taken into account in order to select the most appropriate buoyancy module length.     

柔性叶片垂直轴潮流能水轮机性能分析（英文）

In this study, a vertical axis tidal turbine with flexible blades is investigated. The focus is on analyzing the effect of flexible airfoils types and blade flexibility on turbine net output power. To this end, five different flexible airfoils(Symmetric and Non-symmetric) are employed. The results show that the use of a thick flexible symmetric airfoil can effectively increase output power compared to that achievable with a conventional rigid blade. Moreover, the use of highly flexible blades, as opposed to less flexible or rigid blades, is not recommended.     

Performance analysis of a vertical axis tidal turbine with flexible blades

In this study, a vertical axis tidal turbine with flexible blades is investigated. The focus is on analyzing the effect of flexible airfoils types and blade flexibility on turbine net output power. To this end, five different flexible airfoils (Symmetric and Non-symmetric) are employed. The results show that the use of a thick flexible symmetric airfoil can effectively increase output power compared to that achievable with a conventional rigid blade. Moreover, the use of highly flexible blades, as opposed to less flexible or rigid blades, is not recommended.     

The development of studying flexible pipe bend reinforced by Kevlar fibers

The flexible pipe bend can not only reduce the structural vibration and fluid noise in pipeline, but also realize the flexible connection of a horizontal line and a vertical line and compensate the displacement of three dimensions produced by the shock or vibration of pipeline in the special situations. Up to now, little attention has been paid to study the flexible pipe bend applied in the pipeline of medium or high pressure, because no appropriate framework materials can be used to reinforce it which must endure the burst pressure higher than 10 MPa. The investigation shows that it is possible to produce the flexible pipe bend of medium or high pressure if such fibers with high performance as Kevlar fibers are used to be its reinforced materials. However, its structural designing theory, manufacturing technology and measuring techniques aren‘t yet perfect and systematic, which leads to the instability of the performance of products. Furthermore, few references about its research can be seen. Therefore, it is necessary to systematically and thoroughly develop the structural designing theory, manufacture technology and measuring techniques of flexible pipe bend.     

Stress analysis of the subsea dynamic riser baseprocess piping

Thesubsea dynamic riser base （SDRB） is an important piece of equipment for the floating production platform mooring system.One end is connected to the rigid pipeline, carrying a rigid pipeline thermal expansion load and the other end is connected to a flexible riser, carrying the dynamic load of the flexible riser, so its function is a transition connection between the flexible riser and the rigid pipeline which fixes the flexible riser on the seabed. On the other hand. as a typical subsea product, the design will satisfythe requirements of the standards for subsea products. By studying the stress analysisphilosophy of the topside piping and subsea pipeline, a physical model and procedure for piping stress analysis of the SDRB have been established.The conditions of the adverse design load have been considered, and a combination of the static load from the rigid pipeline and the dynamic load flexibility has also been optimized. And a comparative analysis between the AMSE, DNV and API standards for piping stress with the checking rules has been done.Because theSDRB belongs to the subsea pipeline terminal product, the use of DNV standards to check its process piping stress is recommended. Finally, the process piping stress of the SDRB has been calculated, and the results show that the jacket pipe and the carrier pipe stress of the SDRB process piping satisfy the DNV standards as a whole.The bulkhead cannot be accurately simulated by the AutoPIPE software which uses the FEA software ANSYS inthe detailed analysis, but the checking results will still meet the requirements of the DNV standards.     

Response prediction of long flexible risers subject to forced harmonic vibration

Several research efforts have been directed toward the development of models for response prediction of flexible risers. The main difficulties arise from the fact that the dynamic response of flexible risers involves highly nonlinear behavior and a self-regulated process. This article presents a quasi-steady approach for response prediction of oscillating flexible risers. Amplitude-dependent lift coefficients are considered, as is an increased mean drag coefficient model during synchronization events. Experimental validation of the proposed model was carried out using a 20-m riser model excited by forced harmonic vibration at its top end. Large variations in the hydrodynamic force coefficients, a low mass ratio value, and synchronization events are the main features of the model presented in this article. Experimental validation was provided for the asymmetric, transverse, diagonal, and third vortex regimes.