沉管隧道管节沉放施工技术*

以国内外已建沉管隧道相关施工技术为依托,对常用管节沉放方法进行对比分析.阐述常用管节沉放方法如浮吊法、浮箱沉吊法、升降平台法和抬吊法的施工流程及技术措施,并对4种管节沉放方法的优缺点进行综合比较,给出每种管节沉放方法的适用范围,为沉管隧道管节沉放方法的选择、工艺优化以及新技术研究提供参考依据.     

深中通道首节沉管成功沉放海底

<正>本刊从交通运输部获悉,2020年6月17日,世界首例双向八车道钢壳沉管隧道——广东深中通道首节沉管成功沉放海底,与西人工岛隧道暗埋段实现对接。此次安装采用世界首创的自航式沉管运输安装一体船作业方式,极大提高了施工精度和效率。深中通道全长约24 km,沉管隧道长6. 8 km,由32节沉管组成,沉管浮运安装是项目建设过程中技术难度最大的控制性环节。本次对接的首节沉管长123. 5 m、宽46 m、高10. 6 m,重约6万t。     

沉管隧道管节沉放施工技术

以国内外已建沉管隧道相关施工技术为依托,对常用管节沉放方法进行对比分析。阐述常用管节沉放方法如浮吊法、浮箱沉吊法、升降平台法和抬吊法的施工流程及技术措施,并对4种管节沉放方法的优缺点进行综合比较,给出每种管节沉放方法的适用范围,为沉管隧道管节沉放方法的选择、工艺优化以及新技术研究提供参考依据。     

沉管隧道异形管节安装对接监控技术研究

沉管隧道具有埋深浅、断面大等优势。香港沙中线隧道横跨维多利亚湾,连接九龙和香港岛,由11节沉管组成。文章针对沙中线隧道建设中遇到的异形沉管的安装难题,在研究异形管节坐标系建立、姿态监测系统建立校准、RTK GPS校准的基础上,开发了一套沉管安装对接监控系统,指导了异形沉管E1、E10和E11的安装对接。此外,给出了沉管安装后轴线偏差快速测量方法——铅锤激光仪投点法。与传统的全站仪贯通测量法相比,此安装对接监控系统完全可以满足精度要求,具有明显优势,可广泛推广应用。     

高强度洋流作用下沉管的力学性能研究

沉管水下沉放中,管节与船舶采用缆索连接吊放下沉.为解决外海复杂海况条件下,船管缆系耦合受力的状态与水下管节的位移不受控和缆力超限的问题,通过数值仿真计算和物模试验相结合的方式,分析了不同沉放深度的沉管沉放过程中,船舶受外载荷和管节水下受水动力双重作用时的动力响应情况.通过计算和试验,开展了自由状态下的衰减试验、系泊系统下模型单自由度运动衰减试验、作业状态下沉管和安装船运动响应及各缆绳的受力测量,得到系泊缆、沉管吊缆和安装缆,在浪、流组合作用下的受力和水下运动位移情况,选取了适用于本项目管节沉放施工缆系的关键力学取值,并进行了工程应用验证和对比分析,证明了该研究成果的正确性,研究成果可为类似工程大型构件水下精确沉放和施工提供技术依据.     

海上大直径超长HDPE管段沉放工艺

HDPE管段的沉放工艺直接影响管段水下对接的效率以及成功率,是HDPE管段水下安装工程中的重要环节。针对大直径超长HDPE管段的灌水沉放工艺进行系统研究,将理论分析与现场试验相结合,首次提出采用气囊配合"牺牲绳"控制管段灌水沉放的方法,并得出确定气囊数量的方法与原则,进而提出满足变水深条件下的大直径超长HDPE管的灌水沉放工艺。该工艺已成功应用于沙特吉赞JIGCC取排水工程大直径超长HDPE管段安装工程中,为今后类似工程的建设提供参考。     

波浪作用下沉管隧道管段沉放过程的频域响应(英文)

大型沉管隧道管段的沉放是沉管隧道施工中的关键环节之一.为了解沉管隧道管段沉放过程中的运动特性,对双驳船施工沉放的沉管隧道管段进行了频域计算分析.基于线性波理论和三维分布源法,计算得到波浪作用下沉管管段沉放过程中的波浪荷载及频域运动响应.计算中假定驳船本身的运动较小,忽略了驳船的运动对管段运动响应的影响,缆绳作用力由静力学方法计算.计算结果表明,沉管受到的波浪荷载在靠近水面的位置较大,并随着沉管沉放深度的增加而减小;随着波浪周期的增大,沉管受到的波浪荷载先增大而后减小;沉管的运动响应一般在离水面近的位置较大,并随着沉放深度的增加而减小.     

海流作用下沉管—双驳船沉放系统沉放过程的阻力特性分析

文章通过CFD方法对海流作用下沉管管节与双驳船组成的沉放系统在不同沉放水深时的阻力进行分析,采用RANS方程和SST k-ε湍流模型,利用试验结果验证所用模型和方法的正确性。结合沉放过程三个典型工况,分析90°来流时的流场变化对阻力特性变化产生的影响。结果表明数值结果与试验结果差异较小,驳船和沉管之间的相对位置、沉管沉放深度对流阻力大小影响较大。     

千日奋战 节节平安——大桥海事处护航港珠澳大桥岛隧工程33节沉管水工作业

正3月6日16时,港珠澳大桥最后一节重达7万吨的沉管E30管节历经6个小时10余海里的浮运后,终于安全到达距离伶仃主航道约2.8km、龙鼓西航道约1.3km的港珠澳大桥海底隧道沉放位置实施安装作业,7日8时40分对接成功。至此,历时1 417天,大桥海事处攻克了多项监管难题,圆满完成了港珠澳大桥岛隧工程全部33节沉管施工作业的水上交通安全保障任务,创造了海事部门"零伤     

高强度洋流作用下沉管的力学性能研究（英文）

沉管水下沉放中,管节与船舶采用缆索连接吊放下沉。为解决外海复杂海况条件下,船管缆系耦合受力的状态与水下管节的位移不受控和缆力超限的问题,通过数值仿真计算和物模试验相结合的方式,分析了不同沉放深度的沉管沉放过程中,船舶受外载荷和管节水下受水动力双重作用时的动力响应情况。通过计算和试验,开展了自由状态下的衰减试验、系泊系统下模型单自由度运动衰减试验、作业状态下沉管和安装船运动响应及各缆绳的受力测量,得到系泊缆、沉管吊缆和安装缆,在浪、流组合作用下的受力和水下运动位移情况,选取了适用于本项目管节沉放施工缆系的关键力学取值,并进行了工程应用验证和对比分析,证明了该研究成果的正确性,研究成果可为类似工程大型构件水下精确沉放和施工提供技术依据。     

第十二届深水操作会议和展览会(英文)

正November 4-6,2014Moody Gardens HotelConvention Center/Galveston,TX The Deepwater Operations Conference and Exhibition is celebrating its 12th anniversary this year.This growing event will continue the tradition of excellence in addressing operational challenges involved in developing deepwater resources.We will return to the Moody Gardens Hotel and Convention Center on November 5-7,2014 in Galveston,Texas.     

The 11th International Conference on Hydrodynamics (ICHD 2014)

正19–24 October 2014 SingaporeCONFERENCE THEMES The overall aim of the ICHD Conference is to provide a forum for participants from around the world to review,discuss and present the latest developments in the broad discipline of hydrodynamics and fluid mechanics.The first International Conference on Hydrodynamics(ICHD)was initiated in 1994 in Wuxi,China.Since then,9 more ICHD conferences were held subsequently in Hong Kong,Seoul,Yokohama,Tainan,Perth,Ischia,Nantes,Shanghai and St Petersburg.Evidently the ICHD conference has become an important event among academics,researchers,engineers and operators,working in the fields closely related to the science and technology of hydrodynamics.The 11th ICHD will be held in Singapore in 2014.     

33rd International Conference on Ocean,Offshore and Arctic Engineering （OMAE2014）

正San Francisco,California,June 8-13,2014.OMAE 2014 is the ideal forum for researchers,engineers,managers,technicians and students from the scientific and industrial communities from around the world to:·meet and present advances in technology and its scientific support;·to exchange ideas and experiences whilst promoting technological progress and its application in industry·to promote international cooperation in ocean,offshore and arctic engineering.In line with the tradition of excellence of previous OMAE conferences,more than 900 technical papers are planned for presentation.Outreach for Engineers Specialty Forum This Specialty Forum is designed for students and professionals who may not be familiar with the Ocean and Offshore industry,as well as those who have just recently specialized in this field.     

Catalyzing Coastal Management in Kenya and Zanzibar: Building Capacity and Commitment

Site-based projects were initiated in Chawka Bay-Paje, Zanzibar, and Nyali-Bamburi-Shanzu, Kenya, to demonstrate the benefits of an integrated coastal management (ICM) approach for addressing coastal issues such as tourism development and enhancement of resource-dependent village economies in eastern Africa. A two-year, multidonor project used three primary strategies to make rapid, but sustainable, progress toward ICM. These included using interagency government teams for ICM planning, adopting an internationally recognized framework for ICM as a project ''road map,'' and explicitly incorporating capacity-building strategies into all aspects of the project. Within two years, integrated ICM action strategies, prepared through participatory processes, were being implemented at both sites, and both teams were working to expand the scale and scope of ICM in their nation. More importantly, the project helped create committed, capable, interagency groups that continue to work together to address urgent ICM issues.     

A simplified method for reliability- and integrity-based design of engineering systems and its application to offshore mooring systems

This paper presents a simplified method for the reliability- and the integrity-based optimal design of engineering systems and its application to offshore mooring systems. The design of structural systems is transitioning from the conventional methods, which are based on factors of safety, to more advanced methods, which require calculation of the failure probability of the designed system for each project. Using factors of safety to account for the uncertainties in the capacity (strength) or demands can lead to systems with different reliabilities. This is because the number and arrangement of components in each system and the correlation of their responses could be different, which could affect the system reliability. The generic factors of safety that are specified at the component level do not account for such differences. Still, using factors of safety, as a measure of system safety, is preferred by many engineers because of the simplicity in their application. The aim of this paper is to provide a simplified method for design of engineering systems that directly involves the system annual failure probability as a measure of system safety, concerning system strength limit state. In this method, using results of conventional deterministic analysis, the optimality factors for an integrity-based optimal design are used instead of generic safety factors to assure the system safety. The optimality factors, which estimate the necessary change in average component capacities, are computed especially for each component and a target system annual probability of system failure using regression models that estimate the effect of short and long term extreme events on structural response. Because in practice, it is convenient to use the return period as a measure to quantify the likelihood of extreme events, the regression model in this paper is a relationship between the component demands and the annual probability density function corresponding to every return period. This method accounts for the uncertainties in the environmental loads and structural capacities, and identifies the target mean capacity of each component for maximizing its integrity and meeting the reliability requirement. In addition, because various failure modes in a structural system can lead to different consequences (including damage costs), a method is introduced to compute optimality factors for designated failure modes. By calculating the probability of system failure, this method can be used for risk-based decision-making that considers the failure costs and consequences. The proposed method can also be used on existing structures to identify the riskiest components as part of inspection and improvement planning. The proposed method is discussed and illustrated considering offshore mooring systems. However, the method is general and applicable also to other engineering systems. In the case study of this paper, the method is first used to quantify the reliability of a mooring system, then this design is revised to meet the DNV recommended annual probability of failure and for maximizing system integrity as well as for a designated failure mode in which the anchor chains are the first components to fail in the system.     

含裂纹钢板复合材料修补强度和刚度数值分析

用ANSYS有限元分析软件对复合材料补片修复含边裂纹和中心裂纹钢板的强度和刚度进行了数值分析.引入相对刚度的概念,研究了钻有止裂孔裂纹的长度对损伤钢板相对刚度的影响,分析了损伤钢板刚度复合材料贴片修补效果;引入屈服载荷提高率的概念,分析了损伤钢板强度的修复效果.     

舰艇反鱼雷技术

对目前舰艇反鱼雷技术中的非杀伤、软杀伤和硬杀伤等比较先进的手段进行了阐述,并在此基础上分析研究了舰艇反鱼雷技术的发展趋势。     

混凝土道路、堆场面层裂缝的产生与防治

从混凝土道路、堆场的各个结构层分析裂缝产生的原因,并针对性地说明预防措施,阐述裂缝维修方法。     

利比亚米苏拉塔市萨瓦瓦区5000套住宅项目中心区设计

从确定符合项目实际情况的设计原则入手,通过利比亚米苏拉塔市萨瓦瓦住宅区中心区总体布局和建筑设计两个方面的设计实践,探讨了"传统、现代与文脉"这一当今时代无法回避的文化议题。并且针对具有鲜明文化、宗教和气候特征的建筑设计的特点、方法与风格进行了总结,为今后的实践提供借鉴。     

Community-Based Management for Sustainable Fisheries Resources in Phang-nga Bay,Thailand

Fishing communities, the Government of Thailand Department of Fisheries, local nongovermnental organizations, universities, the Food and Agriculture Organization of the United Nations (FAO), and FAO's Bay of Bengal Program have undertaken a partnership in management of Phang-nga Bay's coastal resources. It is the first project of its kind in Thailand, and although still in the early stages, offers insights that may contribute to our knowledge of how we can improve our management of coastal resources, including the importance of (1) building relationships within the governance process; (2) combining education, enforcement, and economic incentives to achieve compliance; (3) implementing solutions early; and (4) government support of community-based decisions. These insights reinforce trends emerging in other coastal management projects in the Asian region.