扩大长江干线航道通过能力研究

城区段河道规划是关系到城市人民财产、生命安全的重要方面,更是提升城市品位,提高人民生活质量的根本。本文就整体规划方案分析,使水利工程向“美、靓、实”的方向规划,供大家共同探讨。     

武汉天兴洲公铁两用长江大桥正桥工程风险分析与评价

在对我国近年来长江上修建的特殊结构桥梁风险管理工作调研基础上,结合武汉天兴洲公铁两用长江大桥工程特点,对该桥的风险因素进行识别,并建立了风险分析层次结构图,利用层次分析法(AHP)对工程主要风险因素进行了评价,从而有效地指导了工程项目的风险管理工作。     

Characteristics and potential impacts of under-ice river plumes in the seasonally ice-covered Bothnian Bay (Baltic Sea)

The northernmost basin of the Baltic Sea, the Bothnian Bay, is ice-covered for about half the year. During this time, distinct under-ice river plumes develop, even seaward of the smallest rivers, that are substantially thicker and larger in extent than during the summer months. Wind mixing is negligible, and during late spring in April or May, the highest annual discharge occur while the sea is ice covered, thus providing conditions for the formation of extensive under-ice plumes. These plumes are characterised by high levels of trace elements (e.g., Al, Fe and Zn), organic matter (TOC and dissolved organic carbon [DOC]), nutrients and also optically active substances (colored dissolved organic matter, CDOM). The under-ice plumes provide an important pathway for undiluted transport of land-derived substances to the pelagic waters of the basin, affecting the salinity, chemistry and optical properties of coastal waters. Freshwater ice growth on the underside of an existing sea ice sheet also restricts the buildup of sea ice and under-ice algal communities, potentially in large areas along the coasts. Plume water influences the optical characteristics of coastal waters for a period of time after ice break-up, potentially affecting primary production in these areas. Furthermore, the formation of under-ice plumes potentially has a positive feedback on the ice season length due to freshening of the coastal waters (earlier freeze-up) and restricted oceanic heat flux (slower melting).     

三峡工程变动回水区上洛碛滩航道整治

分析川江上洛碛滩滩险特性、碍航原因及三峡水库分别按156m和175m蓄水位运行时期该滩的滩势变化,并根据实测资料分析本整治工程(156m蓄水位运行期)的效果。     

基于智能化道路交通运输管理的模式研究

随着社会经济的不断发展,交通的重要性已经积极的呈现出来,逐渐成为了经济发展的基础部分。正因如此,交通运输管理工作受到了社会各界的重视,建设科学、完善的管理体制与系统势在必行。交通运输管理体制包含了两个方面,分别是铁路交通运输管理系统和公路交通运输管理系统,两者关系密切,虽然相互独立,有能相互统一,两者的运输管理系统的高校发展对交通运输管理的发展起到了奠基作用。     

Road characteristics and environment factors associated with motorcycle fatal crashes in Malaysia

This study aims to determine risk factors contributing to traffic crashes in 9,176 fatal cases involving motorcycle in Malaysia between 2010 and 2012. For this purpose, both multinomial and mixed models of motorcycle fatal crash outcome based on the number of vehicle involved are estimated. The corresponding model predicts the probability of three fatal crash outcomes: motorcycle single-vehicle fatal crash, motorcycle fatal crash involving another vehicle and motorcycle fatal crash involving two or more vehicles. Several road characteristic and environmental factors are considered including type of road in the hierarchy, location, road geometry, posted speed limit, road marking type, lighting, time of day and weather conditions during the fatal crash. The estimation results suggest that curve road sections, no road marking, smooth, rut and corrugation of road surface and wee hours, i.e. between 00.00 am to 6 am, increase the probability of motorcycle single-vehicle fatal crashes. As for the motorcycle fatal crashes involving multiple vehicles, factors such as expressway, primary and secondary roads, speed limit more than 70 km/h, roads with non-permissible marking, i.e. double lane line and daylight condition are found to cause an increase the probability of their occurrence. The estimation results also suggest that time of day (between 7 pm to 12 pm) has an increasing impact on the probability of motorcycle single-vehicle fatal crashes and motorcycle fatal crashes involving two or more vehicles. Whilst the multinomial logit model was found as more parsimonious, the mixed logit model is likely to capture the unobserved heterogeneity in fatal motorcycle crashes based on the number of vehicles involved due to the underreporting data with two random effect parameters including 70 km/h speed limit and double lane line road marking.     

长江干线航道GPS测量控制网建设工程设计与施工

介绍长江干线航道GPS测量控制网建设工程的设计与施工情况。该网是我国大江大河建立的第一个全程覆盖的GPS(C级)测量控制网,也是GPS技术在我国航道管理行业中成功运用的范例。     

敞开式TBM空推步进技术在引松供水工程的应用

引松供水工程4标段隧洞主要采用敞开式TBM进行施工，为节省工期，部分洞段变更为钻爆法施工接应，TBM步进通过。为使TBM在圆形钻爆段快速步进，通过分析TBM在圆形断面空推步进的影响因素，研究钻爆段弧形底板的施工方法、质量控制措施，以及TBM在步进过程出现撑靴撑不到洞壁、撑碎洞壁，底板破碎和底部高低不平等问题的解决措施，使TBM安全、快速步进通过；通过与滑板式步进技术进行对比分析，总结2种步进方式的适应性以及优缺点。     

"RDS-8固化酶"在道路工程中的应用

文章简要地介绍了RDS-8固化酶稳定土的研究,通过室内试验和试验路,证明了RDS-8固化酶稳定土较优良的路用性能及适用范围,在道路工程应用中达到使用安全方便、减少筑路造价、节约能源等效果。     

上海崇明越江通道工程环境地质问题及其防治

上海崇明越江通道工程是长江河口地区重要的国家基础性建设项目,所在区域不良地质条件易给工程施工带来不利影响。文章阐述软土变形、水土突涌、水下砂体运移、浅层天然气、岸带冲淤、砂土液化、地面沉降等环境地质问题及其潜在的工程危害,提出相应的防治对策与技术措施。