Overseas trade vis-a-vis overseas shipping: Growth and performance in India (1999–2009)

Maritime trade has been and even continues to account for about a lion's share of India's total cargo volumes. Despite the growth of multimodal transport (by land, water and air), shipping still continues to be the major mode of transport in the bulk carriage of country's overseas trade. In view of this vital role of shipping, in the first four decades of independence, under the initiative of planned development and active government support, India's shipping and port sector saw dramatic growth in their performance to build adequate national fleet, in keeping up with the transport of overseas cargo. However, the onset of economic liberalization in 1991 has given rise to many new dimensions in the development of the shipping and port sector of the country with a significant redefinition of shipping and port services, in response to the new global trend patterns. For instance, it has also established the new era of containerization in the mode of cargo delivery from the dominance of the era of bulk and break-bulk trade during the decade of sixties and seventies. Moreover, as global competition increases, in response to this emerging trade patterns within this country, India's volume of traffic growth also increases manifold. So, India's shipping and port sectors need, significantly, to build up and furnish their capacity by increasing the frequency of this mode of transport i.e. the growth of the national overseas fleet to meet this surging demand. This paper, therefore, have focused on this role of shipping in such rising overseas trade, with a view to examine the shipping performance (the growth of overseas fleet) in response to the growing overseas trade at all ports of India during the period (1999–2000 to 2008–2009), in terms of both a mathematical model and a graphical representation. Finally, it concludes that the absolute overseas trade, being highly import dependent, have led to a more or less stagnant performance in overseas shipping, owing to the lack of the adequate growth of absolute overseas exports during this period.     

软土路基真空-堆载预压沉降变形特征及卸载时机研究

针对处于沿海滩涂软土路基之上的铁路专用线,采用真空-堆载联合预压的方案加固路基地基,开展了大量的表层沉降、孔隙水压力、分层沉降等观测项目.据实测资料,分析了地基表面的沉降规律,并考虑了地基分层沉降与孔隙水压力的变化规律,全面揭示了整个地基地层的沉降变化特征.运用双曲线合理地预测了工后沉降,且推算出地基整体的固结度;采用工后沉降与地基固结度建立卸载时机判别标准.结果表明:真空-堆载联合预压的处理方案有效地加固了沿海滩涂软土地基;全面考虑地基表面沉降、分层沉降及孔隙水压力,并采用工后沉降与地基固结度相结合的方式,为堆载预压的卸载时机判别标准研究提供了一种新的思路.     

大型海岸工程对水流和泥沙运动的影响研究

在淤泥质海岸建设大型海岸工程,会对周边海域的水沙环境产生一定影响。文章以连云港为例,应用波浪潮流泥沙数学模型,模拟计算了连云港海域大型海岸工程实施后对于水流泥沙运动的影响。研究结果表明:连云港区、徐圩港区以及灌河口双导堤工程实施后,工程区以外的大范围海域潮流场和含沙量场基本没有改变,变化主要集中在工程区和工程区附近近岸海域,总体呈现出动力减弱、含沙量减少的趋势。     

畸形波对直墙式构筑物作用的探索

文章借助一个工程试验,探索性地研究了工程前天然地形下近岸畸形波的存在情况以及工程后畸形波和常规随机波浪对直墙式核电取水构筑物作用的区别,给出了该试验畸形波和常规随机波浪对直墙式构筑物作用的关系及工程设计方面的建议。     

集装箱港区交通系统规划研究

通过分析集装箱港区用地和交通构成的特点,系统地阐述了集装箱港区的交通规划过程,包括现状凋查分析、交通需求预测以及港区重要功能区之间的交通组织设计等内容.将港区内的交通分为集疏运交通和非集疏运交通2大类分别进行研究,重点研究了集疏运交通特别是其交通需求预测.该方法在深圳西部港区疏港道路工程规划和组织设计中得到了应用.     

客运专线抗台风措施研究

客运专线高速车辆轻量化,使其抗强风能力减弱。为保证客运专线安全运输,从线路、路基、桥梁、隧道、站场及电气化设施等方面提出抗台风的设计原则,可采用的运输安全监控预警及运营安全措施。以上研究成果可确保沿海铁路的运营安全,进一步提高沿海铁路建设质量。     

近海T形梁桥上部结构极端波浪作用试验

飓风引起的极端波浪是影响近海桥梁结构安全的重要灾种之一,曾在美国墨西哥湾沿岸造成了大量已建低矮跨海桥梁损毁。探究台风波浪对桥梁上部结构的作用机理,发展波浪作用力计算方法,对保证中国近海地区桥梁结构安全具有重要意义。为准确考虑台风极端波浪的频谱特征,使用连续聚焦波作为入射波,开展了不同波幅、峰值频率和净空的模型试验。试验基于Froude准则采用1∶25缩尺比进行设计,研究对象为T形肋梁桥,试验过程中观测了聚焦波作用下T形梁桥受到的水平和竖向波浪作用力。研究结果表明：采用连续聚焦波作为入射波,通过设置合适的聚焦波周期可以避免二次反射波对入射波的污染,确保试验结果的可信性;波浪作用力中包含了低频准静力和高频砰击力,砰击力峰值一般出现在波浪与结构接触的初始阶段;一般情况下波浪作用力随波幅增大而增大,但存在明显的非单调特征;T形梁桥波浪力随净空增大有明显的先减小后增大的趋势,但峰值频率为0.4 Hz的大波幅聚焦波在净空为2.0～3.0 cm时波浪作用力最大;基于试验结果拟合出的波浪力简便估算方法能够有效计算波浪作用力,可为T形梁桥抗波浪设计提供参考。     

Rising Sea Levels: Helping Decision-Makers Confront the Inevitable

Sea-level rise (SLR) is not just a future trend; it is occurring now in most coastal regions across the globe. It thus impacts not only long-range planning in coastal environments, but also emergency preparedness. Its inevitability and irreversibility on long time scales, in addition to its spatial non-uniformity, uncertain magnitude and timing, and capacity to drive non-stationarity in coastal flooding on planning and engineering timescales, create unique challenges for coastal risk-management decision processes. This review assesses past United States federal efforts to synthesize evolving SLR science in support of coastal risk management. In particular, it outlines the: (1) evolution in global SLR scenarios to those using a risk-based perspective that also considers low-probability but high-consequence outcomes, (2) regionalization of the global scenarios, and (3) use of probabilistic approaches. It also describes efforts to further contextualize regional scenarios by combining local mean sea-level changes with extreme water level projections. Finally, it offers perspectives on key issues relevant to the future uptake, interpretation, and application of sea-level change scenarios in decision-making. These perspectives have utility for efforts to craft standards and guidance for preparedness and resilience measures to reduce the risk of coastal flooding and other impacts related to SLR.     

Vulnerability of Coastal Resort Cities to Mean Sea Level Rise in the Mexican Caribbean

We evaluated the potential economic impacts of increasing sea level rise (SLR) along the Mexican Caribbean where there are major gaps in our understanding of the mechanisms controlling flooding duration and frequency associated to future ecological and economic impacts. We determined the negative economic impact of SLR on infrastructure in the largest urban centers (Cancun, Isla Mujeres, Playa del Carmen, Puerto Morelos and Cozumel) in the state of Quintana Roo (Mexico) that are considered the largest tourism “hot spots” (resort cities) in the country. The tourism industry in this coastal area injects >8 billion dollars year^?1 to the Mexican economy. Our conservative economic assessment regarding the impact of SLR, under a 1?m scenario for all coastal cities is $330 million USD. Further projections for worst scenarios (SLR >2 m) show a non-linear trend where the cost of inaction can reach up to $1.4 billion USD (2?m SLR scenario) and $2.3 billion USD (3?m SLR scenario). This potential loss of infrastructure, as construction cost, is staggering and represents a robust baseline to start evaluating with more detail future impacts of climate variability and change on the Mexican Caribbean coastline.