行标《高速公路可变信息标志信息的显示和管理》简介

对高速公路可变信息标志信息显示进行有效的管理,将有利于信息实时、按序、组合地显示,并实现整体控制管理模式,从而减少高速公路的重现性拥挤、堵塞,提高高速公路营运的安全性。

高速公路

谁把长虹铺在大地上 谁给车轮插上翅膀 谁挽彩霞编织红地毯 谁将平安装满行囊 啊

高职《高速公路应急与安全分析》课程模块的项目化实施

《高速公路应急与安全分析》是高职道路运输管理专业和安全技术与管理专业必修课程《高速公路运营管理》的其中一个模块,培养学生高速公路应急管理与安全组织所必须的理论知识和技能。高职学生的学习基础不够扎实,对于理论性较强的课程学习兴趣不够浓厚。本文以突出专业技能、提高高职学生学习兴趣为出发点,经过教学实践,以“引入典型案例---编制专项预案---实施应急演练---进行安全分析---提出整改方案”为课程实施流程,阐述笔者项目化课程改造实施的教学心得。

这段高速路为何老出事故?——对石太高速公路河北段安全隐患的调查

石家庄至太原高速公路在接近山西省的河北段上,有一个井陉服务区,这是一个交通事故高发区。日前记者对这段高速公路事故频发的原因进行了调查。

广西出台高速公路绿化林带造林绿化管理办法

为加快我区绿色通道建设,把我区高速公路建成高标准、高质量的绿色长廊,日前,自治区绿化委员会、森林防火指挥部、交通厅和自治区林业局联合出台<广西壮族自治区高速公路绿化林带造林绿化管理暂行办法>.

如何做好高速公路安全行车

随着经济的不断发展，高速公路成为公路运输的主要依靠，要想很好的掌握高速公路行车要求及驾驶操作要领，广大驾驶员们必须严格遵守《高速公路交通管理办法》等有关法规和操作过程，其具体要求为：

Decision model and algorithm for traffic rescue resource dispatching on expressway

In order to solve the problems of potential incident rescue on expressway networks, the opportunity cost-based method is used to establish a resource dispatch decision model. The model aims to dispatch the rescue resources from the regional road networks and to obtain the location of the rescue depots and the numbers of service vehicles assigned for the potential incidents. Due to the computational complexity of the decision model, a scene decomposition algorithm is proposed. The algorithm decomposes the dispatch problem from various kinds of resources to a single resource, and determines the original scene of rescue resources based on the rescue requirements and the resource matrix. Finally, a convenient optimal dispatch scheme is obtained by decomposing each original scene and simplifying the objective function. To illustrate the application of the decision model and the algorithm, a case of the expressway network is studied on areas around Nanjing city in China and the results show that the model used and the algorithm proposed are appropriate.

Placement distance of freeway exit advance guide sign and its safety impacts

To remedy the empirical pitfalls of current chinese specifications and MUTCD 2009 guidelines in determining the placement distance of freeway exit advance guide signs,the driving maneuver of exiting traffic is analyzed and the factors influencing placement distance are explored.Variables including the number of lanes,lane width,lane-changing time,driver＇s visual characteristics,sign installation methods and operating speeds on both freeway mainlines and exit ramps are found significant in explaining exit safety.Three different installation methods,namely ground installation,overhead installation and median installation,are introduced and their applicable conditions are given.Models,with the same structure among the three installation methods,are developed to compute the placement distance under different roadway geometric and traffic conditions.Taking overhead installation as an example,simulation results in TSIS-CORSIM show that the proposed distance reduces the number of lane changes in the area from the ramp nose to 500 m upstream by 58.93% compared with current Chinese specifications and 27.35% compared with MUTCD 2009 guidelines.Thus,the distances recommended in this paper have a better safety performance.

Analysis of Heavy Metal Content in Food Crops Planted Along the Shaanxi Inner Mongolia Expressway

To understand the effect of the running of Shaanxi Inner Mongolia Expressway on food crops planted along the sides, we determined the heavy metal contents(Zn, Pb, Cu and Cb) in the digestion solutions of the root, stem and leaf from rice and corn. The results showed that highway promoted the accumulation of heavy metal elements in corn and rice. Compared with the CKs(crops produced where no highway extend), contents of heavy metal elements in two crops tested from two sampling sites were both over standard. This indicates that food crops planted within 100 m away from the highway are been polluted by heavy metals, which is directly related with the running of Shaanxi Inner Mongolia Expressway. Based on this, the areas within 100 m away from the highway are not suggested to cultivate food crops.

Expressway traffic flow prediction using chaos cloud particle swarm algorithm and PPPR model

Aiming at the real-time fluctuation and nonlinear characteristics of the expressway short-term traffic flow forecasting the parameter projection pursuit regression PPPR model is applied to forecast the expressway traffic flow where the orthogonal Hermite polynomial is used to fit the ridge functions and the least square method is employed to determine the polynomial weight coefficient c.In order to efficiently optimize the projection direction a and the number M of ridge functions of the PPPR model the chaos cloud particle swarm optimization CCPSO algorithm is applied to optimize the parameters. The CCPSO-PPPR hybrid optimization model for expressway short-term traffic flow forecasting is established in which the CCPSO algorithm is used to optimize the optimal projection direction a in the inner layer while the number M of ridge functions is optimized in the outer layer.Traffic volume weather factors and travel date of the previous several time intervals of the road section are taken as the input influencing factors. Example forecasting and model comparison results indicate that the proposed model can obtain a better forecasting effect and its absolute error is controlled within [-6,6] which can meet the application requirements of expressway traffic flow forecasting.

Hierarchical decision-making system for real-time freeway incident response

The artificial intelligence technique is used to generate a freeway incident response plan. The incident response framework based on rule-based reasoning, case-based reasoning and Bayesian networks reasoning is presented. First, a freeway incident management system （RK-IMS） based on rule-based reasoning is developed and applied for incident management in the northern section of the Nanjing-Lianyunguang Freeway. Then, field data from the two-year long operations of the RK-IMS are analyzed. Representations of incident case structures and Bayesian networks（BNs） structures related to incident responses are deduced. Finally, the k-nearest neighbor （k-NN） algorithm is applied to calculate the similarities of the cases. The preplan generation and the control strategy by integrating the k-NN algorithm are also developed. The model is validated by using incident data of the year 2006 from the RK-IMS. The comparison results indicate that the proposed algorithm is accurate and reliable.

Construction of crash prediction model of freeway basic segment based on interactive influence of explanatory variables

In order to improve the prediction precision of the safety performance function （SPF） of freeway basic segments, design and crash data of 640 segments are collected from different institutions. Three negative binomial （NB） regression models and three generalized negative binomial （GNB） regression models are built to prove that the interactive influence of explanatory variables plays an important role in fitting goodness. The effective use of the GNB model in analyzing the interactive influence of explanatory variables and predicting freeway basic segments is demonstrated. Among six models, the two models （one is the NB model and the other is the GNB model. ） which consider the interactive influence of the annual average daily traffic （AADT） and length are more reasonable for predicting results. Furthermore, a comprehensive study is carried out to prove that when considering the interactive influence, the NB and GNB models have almost the same fitting performance in estimating the crashes, among which the GNB model is slightly better for prediction performance.

Slope Protection with Vegetation of Baoji(Shaanxi)-Hanzhong(Shaanxi) Expressway

With expressway development and environment protection consciousness improving, slope protection technology with vegetation has drawn much more attention. From the perspective of ecology, Baoji-Hanzhong Expressway maximized slope protection technology with vegetation and formed attracting landscapes on basis of eco-protection. This research introduced the technology of Baoji-Hanzhong Expressway, and explored a low-cost and effective biological slopeprotection way, suitable for Baoji-Hanzhong Expressway, according to slope protection technologies, at home and abroad, with botany, water and soil conservation engineering, and architecture, which fixed and stabilized slopes, prevented rainfall scouring, and advanced slope protection development in China.

Evaluation model for freeway incident management system

In order to evaluate the general situation and find special problems of the freeway incident management system, an evaluation model is proposed. First, the expert appraisal approach is used to select the primary evaluation index. As a result, 81 indices and the hierarchical structures of the index such as the object layer, the sub-object layer, the criterion layer and the index layer are determined. Then, based on the fuzzy characteristics of each index layer, the analytical hierarchy process（AHP）and the fuzzy comprehensive evaluation are applied to generate the weight and the satisfaction of the index and the criterion layers. When analyzing the relationship between the sub-object layer and the object layer, it is easy to find that the number of sub-objects is too large and sub-objects are significantly redundant. The partial least square （PLS） is proposed to solve the problems. Finally, an application example, whose result has already been accepted and employed as the indication of a new project in improving incident management, is introduced and the result verifies the feasibility and efficiency of the model.

Hazard assessment of landslide disaster using information value method and analytical hierarchy process in highly tectonic Chamba region in bosom of Himalaya

The present study is focused on a comparative evaluation of landslide disaster using analytical hierarchy process and information value method for hazard assessment in highly tectonic Chamba region in bosom of Himalaya. During study, the information about the causative factors was generated and the landslide hazard zonation maps were delineated using Information Value Method(IV) and Analytical Hierarchy Process(AHP) using Arc GIS(ESRI). For this purpose, the study area was selected in a part of Ravi river catchment along one of the landslide prone Chamba to Bharmour road corridor of National Highway(NH^(-1)54 A) in Himachal Pradesh, India. A numeral landslide triggering geoenvironmental factors i.e. slope, aspect, relative relief, soil, curvature, land use and land cover(LULC), lithology, drainage density, and lineament density were selected for landslide hazard mapping based on landslide inventory. Landslide hazard zonation map was categorized namely "very high hazard, high hazard, medium hazard, low hazard, and very low hazard". The results from these two methods were validated using Area Under Curve(AUC) plots. It is found that hazard zonation map prepared using information value method and analytical hierarchy process methods possess the prediction rate of 78.87% and 75.42%, respectively. Hence, landslide hazardzonation map obtained using information value method is proposed to be more useful for the study area. These final hazard zonation maps can be used by various stakeholders like engineers and administrators for proper maintenance and smooth traffic flow between Chamba and Bharmour cities, which is the only route connecting these tourist places.

Slope Debris Flows in the Wenchuan Earthquake Area

Avalanches and landslides,induced by the Wenchuan Earthquake on May 12,2008,resulted in a lot of disaggregated,solid material on slopes that could be readily mobilized as source material for debris flows.Rainstorms triggered numerous slope debris flows with great damage to highways and rivers over the subsequent two years.Slope debris flows(as opposed to channelized debris flows) are defined as phenomena in which high-concentration mixtures of debris and water flow down slopes for short distances to highways and river banks.Based on field investigations and measurements of 19 slope debris flows,their main characteristics and potential mitigation strategies were studied.High rainfall intensity is the main triggering factor.Critical rainfall intensities for simultaneous occurrence of single,several and numerous slope debris flow events were 20 mm/day,30mm/day,and 90 mm/day,respectively.Field investigations also revealed that slope debris flows consist of high concentrations of cobbles,boulders and gravel.They are two-phase debris flows.The liquid phase plays the role of lubrication instead of transporting medium.Solid particles collide with each other and consume a lot of energy.The velocities of slope debris flows are very low,and their transport distances are only several tens of meters.Slope debris flows may be controlled by construction of drainage systems and by reforestation.