成南高速公路交通事故的基本特点分析

在本文,作者通过对成都至南充南高速公路(0～75km)自2002年12月通车到2004年11月所发生的交通事故进行了统计,分析了该路段交通事故的特点、成因,在此基础上提出了预防和减少高速公路交通事故的对策。     

Development of the Driving Simulation System MOVIC-T4 and Its Validation Using Field Driving Data

Underground urban expressways are a possibility for solving many existing transportation-related problems, such as traffic congestion in high density areas and the division of neighborhoods due to elevated roadways. However, they may also pose high risks regarding traffic safety. Therefore, it is important for a pre-analysis of traffic safety to be made. This paper describes recent efforts to develop a driving simulation system, MOVIC-T4, for traffic safety analysis of underground urban expressways. In order to develop a small portable simulator, a small-sized motion-base with two-degrees-of-freedom is used to duplicate accel-eration cueing together with a head-mounted-display (HMD) for the visual system. An overview of this sys-tem is given and the reliability of driving data obtained from the experiments using MOVIC-T4 is discussed through a validation study using field driving data. The results of validation indicate that the perceived speed, distance headway, and physiological data in the simulator show the almost same trend as that in the real world, but larger decelerations tend to be produced in the simulator.     

On the Effects of Central Japan Expressway＇s Commuter Toll Discount Policy in Nagoya Area

Road pricing policies have two equally important objectives that have to be considered： the optimal use of the road network and the fiscal sustainability for the management of the network. The aim of this work is to examine the effects on these two objectives of a recent pricing policy implemented in Japan＇s expressway networks. Recently the Nippon （Japan） Expressway Companies （NEXCO, operators of Japan＇s nation wide expressway network） have implemented several toll discount policies for users equipped with electronic toll collectors （ETCs）. One of the policies is the commuter discount policy that discounts 50% for a journey on the NEXCO expressway no longer than 100 km during the commuting peak hours. This paper examines its effect on congestion reduction in the road network of Nagoya area and its influence on the use of expressways operated by another major local public expressway company in Nagoya. The congestion easing effect of this policy is compared with a potential marginal cost pricing scheme. These observations suggest that policy coordination regarding toll levels is needed for expressway corporations and transportation authorities for improving transportation efficiency of utilization of the whole network.     

基于微观换道的高速公路双车道出口辅助车道长度研究

为研究辅助车道长度确定的基本原理和合理长度,采用无人机航拍视频及YOLOv3目标检测算法提取双车道出口辅助车道路段车辆的原始轨迹数据,通过卡尔曼滤波和Frenet坐标系转换,得到了车辆微观换道特性和速度分布特征。以修正双曲正切函数换道模型拟合换道轨迹,左、右换道拟合优度分别为97.48 %、97.62 %。根据路段车辆运行和微观换道特性,建立了双车道出口辅助车道长度计算模型,将辅助车道划分为右换道段、反应段、等待段和左换道段4个组成部分。研究表明：出口辅助车道长度中最主要的影响因素是换道长度,其与行驶速度正相关,和《路线规范》相比,明确了辅助车道最小长度的计算原理,界定了辅助车道的范围,为设计中灵活运用提供了参考。     

城市地下快速路入口段火灾烟气蔓延规律

依托上海北横通道泸定路枢纽工程,建立依托工程的全尺寸仿真模型,选取城市地下快速路入口段的主线风速和匝道风速作为变量,研究火灾发生后隧道内人员安全高度处的温度、能见度、CO浓度等变化规律。结果表明,主线风速与匝道风速的提高都会导致温度下降速率减缓,能见度上升,CO浓度降低,但是匝道风速对烟气的影响要弱于主线风速的影响。主线与匝道共同提供排烟风速时,保持临界风速即可有效排烟,主线为1.72 m/s,匝道为1.84 m/s。     

快速路匝道汇入方案优化及软件仿真

针对城市快速路交通压力日益增长,匝道汇入处经常形成拥堵、交通事故频发等现状,结合当前城市快速路现状,通过理论计算和仿真实验方法,对现有汇入方案进行分析和优化,提出了“限速增道”汇入方案.方案在匝道汇入处采取隔离和限制措施,适当减少主、匝道车道宽度,降低车辆速度,引主导、匝道车辆各行其道,减少相互干扰,最终达到提高汇入处通行能力的目的.仿真实验数据显示,方案的单位时间车流量、通行速度、排队长度等交通指标均明显优于其它方案,效果明显.“限速增道”方案在现有车道宽度较宽的城市快速路上可以采用.     

浅析太原市快速路系统构建与布局

通过对太原市现状道路网、城市空间演变趋势及城市快速路系统的影响因素等综合分析。阐述了太原市快速路系统的构建思路和规划布局。     

高速公路C50高强高性能混凝土的配制

文章通过试验方法，论证利用漳州本地区的原材料，选用高效减水剂和一级粉煤灰，水泥用量控制在425kg／m^3以内，顸制砼坍落度控制在50mm-70mm，泵送砼坍落度控制在180mm-160mm。也能配制C50的高强度性能砼。     

汾阳至离石高速公路沥青路面车辙病害调查及技术处治

文章对汾离高速公路沥青路面车辙情况进行调查，并对产生路面车辙的因素进行详细分析，提出了路面处治技术方案。     

高速公路沥青路面病害修补作业操作要领

结合自己在高速公路养护中的实践经验，介绍了沥青路面灌缝修补的工艺流程及修补技术要求、病害的检测等。