跨越高速公路转体桥梁设计与施工控制

随着各地路网密度的不断提高,大量跨越已运营高速公路的桥梁建设工程日益增多,桥梁方案的选择尤为关键。其中平面转体施工桥梁因能最大限度减少对高速公路正常交通的影响,在跨线桥梁上的优越性也越来越明显。本文以一假想高速公路立交桥的建设,介绍平面转体桥梁的转体设计和施工控制。     

高速公路事件管理中主要部门影响权重灰色关联度分析

为了分析高速公路事件管理中主要部门影响权重组成结构的合理性,本文引入现实权重与理想权重的灰色关联度来解决。在理想权重的获得中,分别用G1序关系法和熵值法确定专家评分能力因素中的主客观权重,并用评价目标最大化的方法来处理组合权重以尽量体现专家评分水平的差距。最后对某高速公路的情况进行了计算,以验证此方法的实用性。     

高速公路出入口OD矩阵推算方法

研究已建高速公路历年断面流量变化规律,对制定各项管理措施和项目评估都至关重要。在我国断面交通流量硬件观测设施不十分普及的情况下,各收费站口数据的整理统计分析显得尤为重要。本文结合高速公路实际,提出以收费站数据为基础,进行高速公路出入口OD流量推算的一般方法,并对太旧高速公路2002年某天数据进行实例分析。     

浅谈高速公路自动化收费系统车道设备的维护

阐述了高速公路自动化收费系统的维护管理,介绍了自动化收费系统的构成和车道设备的维护,并分析了主要设备故障现象及处理方法.     

A multi-class model-based control scheme for reducing congestion and emissions in freeway networks by combining ramp metering and route guidance

The paper proposes a multi-class control scheme for freeway traffic networks. This control scheme combines two control strategies, i.e. ramp metering and route guidance, in order to reduce the total time spent and the total emissions in a balanced way. In particular, the ramp metering and route guidance controllers are feedback predictive controllers, i.e. they compute the control actions not only on the basis of the measured system state, but also on the basis of the prediction of the system evolution, in terms of traffic conditions and traffic emissions. Another important feature of the controllers is that they have a multi-class nature: different classes of vehicles are considered and specific control actions are computed for each class. Since the controllers are based on a set of parameters that need to be tuned, the overall control framework also includes a module to properly determine the gains of the controllers. The simulation analysis reported in the paper shows the effectiveness of the proposed control framework and, in particular, the possibility of implementing control policies that are specific for each vehicle type.     

Improved vehicle classification from dual-loop detectors in congested traffic

Vehicle classification is an important traffic parameter for transportation planning and infrastructure management. Length-based vehicle classification from dual loop detectors is among the lowest cost technologies commonly used for collecting these data. Like many vehicle classification technologies, the dual loop approach works well in free flow traffic. Effective vehicle lengths are measured from the quotient of the detector dwell time and vehicle traversal time between the paired loops. This approach implicitly assumes that vehicle acceleration is negligible, but unfortunately at low speeds this assumption is invalid and length-based classification performance degrades in congestion.To addresses this problem, we seek a solution that relies strictly on the measured effective vehicle length and measured speed. We analytically evaluate the feasible range of true effective vehicle lengths that could underlie a given combination of measured effective vehicle length, measured speed, and unobserved acceleration at a dual loop detector. From this analysis we find that there are small uncertainty zones where the measured length class can differ from the true length class, depending on the unobserved acceleration. In other words, a given combination of measured speed and measured effective vehicle length falling in the uncertainty zones could arise from vehicles with different true length classes. Outside of the uncertainty zones, any error in the measured effective vehicle length due to acceleration will not lead to an error in the measured length class. Thus, by mapping these uncertainty zones, most vehicles can be accurately sorted to a single length class, while the few vehicles that fall within the uncertainty zones are assigned to two or more classes. We find that these uncertainty zones remain small down to about 10 mph and then grow exponentially as speeds drop further.Using empirical data from stop-and-go traffic at a well-tuned loop detector station the best conventional approach does surprisingly well; however, our new approach does even better, reducing the classification error rate due to acceleration by at least a factor of four relative to the best conventional method. Meanwhile, our approach still assigns over 98% of the vehicles to a single class.     

中国高速公路事故特点及分布规律研究

中国的高速公路建设现在正处于快速发展时期,其事故发生率与事故严重程度与国外高速公路相比均高出很多,可以预见的是高速公路的安全形势将随着经济和社会的发展,以及汽车保有量和高速公路通车里程的增加,变得越来越严峻。在大量调研高速公路事故数据的基础上,利用统计分析的方法,研究讨论了我国高速公路交通事故的基本特点及分布规律,得出了一系列有价值的结论。研究结果可以为高速公路的交通安全管理与控制,以及交通事故的预测和预防提供良好的参考和借鉴。     

上跨式互通立交出口匝道与地面道路衔接部渠化设计研究

互通立交出口匝道与地面道路衔接部是高速公路与地面衔接道路交通流转换的枢纽,研究其渠化设计方法对优化互通立交及其周边路网的交通流运行状态,提高区域路网服务水平具有重要的意义。本文首先在现场调查的基础上,分析了上跨式互通立交出1：3匝道与地面道路衔接部的交通流运行特性,然后提出了典型互通立交出口匝道与地面道路衔接部的渠化设...     

浅谈铁岭至朝阳高速公路阜新至朝阳段绿化与景观设计

高速公路绿化呈线性分布,通过中央分隔带、填挖方段、互通立交区、隧道洞口、服务区及收费站养护工区绿化等六个方面来阐述铁岭至朝阳高速公路阜新至朝阳段绿化与景观设计.     

山岭区高速公路设计新理念

通过对辽宁省东部项目鹤岗至大连国家高速公路桓仁(辽吉界)至丹东(古城子)段前期工作的研究,重点分析项目影响区内高速公路线形设计、环境保护、可持续发展等主要问题,提出山岭区高速公路设计新理念.