深圳市过境与疏港货运交通特性分析

对深圳市过境与疏港货运交通特性进行研究,分析了空间需求分布和交通流向分布,识别过境与疏港货运交通走廊,对存在的问题进行诊断及成因剖析。研究成果将为深圳市过境、疏港货运交通组织提供基础资料,对其他城市的货运交通规划和组织也有借鉴作用。     

运营状态下杨浦大桥模态试验与状态评估方法研究

利用频域一空间域分解法,建立桥梁运行模态识别方法.该方法对桥梁在实际运行状态下车辆激励的响应测量数据进行无偏功率谱估计;然后采用奇异值分解技术,将随机响应数据空间分解成信号和噪声2个子空间,得出模态指示函数;并利用空间模态滤波技术分离出单一模态,准确识别出桥梁结构的模态参数.通过对杨浦大桥进行动力试验,测试桥梁在环境激励下的振动信息,采用该方法分析得到桥梁结构的动力参数,并与有限元计算结果相对比,有效实现了对桥梁结构整体状态和工作性能的评估.     

旧桥大边梁加宽加固承载潜力研究

大边梁加宽加固旧桥是一种很有效的桥梁加固方法。通过对不同纵横向刚度比的大边梁加宽加固效果进行对比．探讨其对发挥旧桥结构承载潜力的作用,以确定较好的加固方式,可供桥梁加固时参考。     

SLG6792CF-1型流动银行车的设计

提出流动银行车的设计依据和要求,介绍为满足功能而实施的方案.     

芜湖长江公铁大桥2号墩围堰气囊法下水设计

为给双壁钢套箱围堰气囊法下水施工组织设计提供理论支撑,以商合杭铁路芜湖长江公铁大桥2号主墩圆端形双壁钢套箱围堰为例,研究双壁钢套箱围堰气囊法下水的设计方法。结合围堰拼装场地地形条件进行坡道与气囊布置并进行后端地笼计算。将围堰下水过程分解为多个工况进行静力计算,在计算过程中考虑气囊受力不均对围堰角度的修正。运用能量守恒原理简便求解围堰下水时的初速度和围堰入水后的漂移长度。采用该方法指导芜湖长江公铁大桥2号主墩围堰下水,过程顺利、可控,证明该方法正确可行。该方法可同时适用于圆形、矩形、哑铃形等各类双壁钢套箱围堰气囊法下水设计。     

湛江港航道会船区设置方案研究

随着航运的快速发展,大型船舶通过进出港航道占用航道时间越来越长,在进港航道设置会船区是十分必要的。现行规范中对于会船区的有关规定及计算尚不明确。针对湛江港航道里程长、规模大、通航环境复杂的客观实际,在对现状船型尺度调研的基础上,分析了拟建会船区的水深、波浪、流速条件。提出了30万、15万t不同船舶组合通航方案,并计算了统一断面与复式断面两种形式下的航道通航宽度,确定会船区长度、宽度、转弯半径、设计底高程等参数,选取了水深良好、位置恰当的会船区平面布置方案。     

界牌枢纽船闸引航道优化设计

针对界牌枢纽改建船闸工程上、下游引航道口门区横流超标的问题,通过调整引航道分水墙长度与挂板高程,通过水流条件试验,得到合理可行的引航道平面优化布置方案;针对下游引航道地质条件突变、原设计采用的混合式结构不再适用的问题,通过进行重力式结构与重力墩+挂板结构的经济技术比选,确定更改方案。结果表明,重力式结构的抗船舶撞击能力强且施工简单,增加投资略高,可作为推荐方案。     

Does a circular high-speed rail network promote efficiency and spatial equity in transport accessibility? Evidence from Hainan Island,China

This paper investigates the efficiency and spatial equity impacts of a unique island-looping high-speed rail (HSR) network in Hainan province, China. An integrated network and raster-based model is applied to accurately measure the accessibility indicators. We perform analysis at four different geographical planning levels – island, corridor, spillover, and county level. The HSR with a non-polarized topology can increase the accessibility of the entire island and corridor, but only leads to a slight increase in the spillover areas without HSR stations. HSR construction also leads to spatial cohesion for the entire island and corridor. Although the circular HSR network consists of several HSR stations distributed relatively equally, the results show that counties contribute differently to the cohesion of the entire island due to the varied initial level of accessibility values. Moreover, the county-level analysis reveals that the internal changes of each county are also different with balancing, polarization, and neutral effects appearing. Therefore, the internal equity of counties needs to be combined with their external contributions to global equity. Our framework permits policymakers to make customized HSR transport policies at different planning levels, particularly for an isolated area.     

India’s air traffic: towards an empirical framework for systems analysis

The paper explores patterns of flows within India’s Air Traffic System through the lens of carriers’ networks and route structures between 2006 and 2014. Through observations of frequency distributions and their distinct patterns an analytic framework is derived heuristically by means of classification and aggregation. The well-known skewed traffic distribution which spatially concentrates traffic around relatively few airports serves as the starting point for decomposing the air traffic system (ATS) into its constituent route types. Airline operations along distinct route classes allows for classifying individual carrier’s network features as an embedded part of the system. Discussion of their role includes a spatial component. Inferences about development paths – past, present, future – of the Indian commercial ATS can be made.     

A constraint programming model with time uncertainty for cooperative flight departures

The lack of a proper integration of strategic Air Traffic Management decision support tools with tactical Air Traffic Control interventions usually generates a negative impact on the Reference Business Trajectory adherence, and in consequence affects the potential of the Trajectory-Based Operations framework. In this paper, a new mechanism relaying on Reference Business Trajectories as a source of data to reduce the amount of Air Traffic Controller interventions at the tactical level while preserving Air Traffic Flow Management planned operations is presented. Artificial Intelligence can enable Constraint Programming as it is a powerful paradigm for solving complex, combinatorial search problems. The proposed methodology takes advantage of Constraint Programming and fosters adherence of Airspace User’s trajectory preferences by identifying tight interdependencies between trajectories and introducing a new mechanism to improve the aircraft separation at concurrence events considering time uncertainty. The underlying philosophy is to capitalize present degrees of freedom between layered Air Traffic Management planning tools, when sequencing departures at the airports by considering the benefits of small time stamp changes in the assigned Calculated Take-Off Time departures and to enhance Trajectory-Based Operations concepts.