公路曲线测设的新方法

本文提出公路曲线测设的一种新方法，该方法具有快速、准确、方便、减少误差积累的优点．文章从一般测设的几种方法开始，给出了新方法的计算公式及操作过程．     

防雪栅设计高度的数值仿真研究

防雪栅是一种有效防治公路风吹雪雪害的措施之一。本文基于雪害形成机理,论述了公路风吹雪雪害数值仿真的思路和方法,并针对路堤这一典型路基断面形式,运用该仿真技术,就防雪栅设计高度对防雪效果的影响进行了研究,其结果与国内外已有的研究成果相吻合,从而为防雪栅及其他防雪设施的设计提供了一种新的分析方法。     

Relating Cost Growth from the Initial Estimate to Design Fee for Transportation Projects

Intuitively, there should be a relationship between the size of the design fee for a transportation project and the quality of the resulting design. This study sought that relationship by looking at the fee expressed as a percentage of the construction cost and the final construction cost growth from the engineer’s initial estimate of the construction cost at the time the design contract was awarded. The research team analyzed 31 projects from the Oklahoma Turnpike Authority with a total construction value of $90 million. The projects were divided into road and bridge projects. Based on the results of the analysis, it seems that as the design fee decreases, the absolute percentage of construction cost growth from the engineer’s early estimate increases. The relationship is strongest for bridge projects, which tend to be more technically complex to design than roadway projects. This confirms for U.S. projects the result of an earlier study in Saudi Arabia. This paper concludes that the design fee should be viewed as an investment at a point in time where the ability to impact the project is the highest and can accrue the benefit of reduced cost growth.     

邮电网络与信息高速公路

介绍了深圳市邮电局计算机网络的体系结构与系统功能，并通过分析网络建设过程中所遇到的问题，指出了我国信息高速公路建设中可能出现和应该注意的问题。     

A novel approach for analyzing severe crash patterns on multilane highways

This study presents a novel approach for analysis of patterns in severe crashes that occur on mid-block segments of multilane highways with partially limited access. A within stratum matched crash vs. non-crash classification approach is adopted towards that end. Under this approach crashes serve as units of analysis and it does not require aggregation of crash data over arterial segments of arbitrary lengths. Also, the proposed approach does not use information on non-severe crashes and hence is not affected by under-reporting of the minor crashes. Random samples of time, day of week, and location (i.e., milepost) combinations were collected for multilane arterials in the state of Florida and matched with severe crashes from the corresponding corridor to form matched strata consisting of severe crash and non-crash cases. For these cases, geometric design/roadside and traffic characteristics were derived based on the corresponding milepost locations. Four groups of crashes, severe rear-end, lane-change related, pedestrian, and single-vehicle/off-road crashes, on multilane arterials segments were compared separately to the non-crash cases. Severe lane-change related crashes may primarily be attributed to exposure while single-vehicle crashes and pedestrian crashes have no significant relationship with the ADT (Average Daily Traffic). For severe rear-end crashes speed limit, ADT, K-factor, time of day/day of week, median type, pavement condition, and presence of horizontal curvature were significant factors. The proposed approach uses general roadway characteristics as independent variables rather than event-specific information (i.e., crash characteristics such as driver/vehicle details); it has the potential to fit within a safety evaluation framework for arterial segments.     

几种相关新旧公路规范荷载效应的比较

对现行的JTGD60—2004《公路桥涵设计通用规范》、CJJ77—1998《城市桥梁设计荷载标准》与原来的JTJ021—1989《公路桥涵设计通用规范》之间不同荷载方式和取值进行了比较,并分别对他们引起的荷载效应之间存在的实际差异进行了比较和分析,从而给老桥改扩建和利用时,经常碰见的上述三个规范、标准之间的比较问题提供了切实可行的依据。     

浅谈公路工程中沥青混合料离析的控制方法

从原材料和沥青混合料的施工等方面全面分析了沥青路面混合料离析产生的原因及过程,提出了在施工中防止沥青混合料离析的技术措施,以有效控制离析,提高沥青路面的质量,从而延长路面的使用寿命。     

高速公路筑养过程中的防雷措施

针对雷电灾害对高速公路的危害,分析了雷电侵入高速公路机电系统的途径,介绍了防雷接地的种类和作用,提出了高速公路机电工程的防雷措施并作了具体阐述,以期减少雷击造成的损失,保证高速公路正常运行。     

上海高速公路收费站拥堵状况和扩容改造措施

上海市高速公路收费站拥堵问题日益突出,已影响到高速公路的服务质量。拥堵原因主要有:交通量明显超过设计通行能力、部分收费站设计通行能力过低、收费站出口疏解不畅。扩容改造措施主要有:收费车道外侧拓建、建设前后分离式网架收费站、不停车电子收费(ETC)改造、可变车道、一岛双亭。目前广泛使用的是拓建收费车道和进行ETC改造。特别是ETC车道通行能力可几倍于人工收费车道,且可降低收费站成本、节约收费人工,将是解决收费站拥堵的有力措施,目前正处于高速发展中。