公路路面冬季养护的对策与措施

公路在使用过程中由于交通量及超限超重车辆的快速增长,给公路养护提出了新的要求。公路的病害日益突出,特别是在冬季,如果不及时进行冻前整修,路面病害更加严重:如何处理路面冰冻和积雪,也是一个迫切需要解决的问题。针对以上问题,并根据实际情况提出了冬季公路路面修补的新方法。     

水泥混凝土路面病害成因与检测处治技术

在对水泥混凝土路面主要病害成因及其影响因素进行分析的基础上,提出一系列路面性能检测评价方法与病害处理技术。     

沥青混凝土路面损坏的防治

造成沥青混凝土路面损坏的主要原因是水损坏、施工问题、超载运输和路面结构设计的不完善,不同的地区产生病害的原因不尽相同,防治的对策也不同.根据青海特殊的地理环境和气候特点,分析了干线公路沥青混凝土路面产生病害的原因及防治措施.     

南友高速公路沥青混凝土路面病害及养护对策

南友高速公路是广西首条使用沥青混凝土路面的高速公路，文章通过分析南友高速公路运营期间出现的裂缝、坑槽、车辙及路面沉陷等病害现象及成因，介绍了沥青混凝土路面病害养护对策及采用的修补材料、施工工艺和施工设备，以供借鉴。     

乌鲁木齐城市道路服役状研究及病害成因浅析

随着我国经济高速发展,作为新疆省经济文化中心,乌鲁木齐逐渐成为了我国同中亚等邻国交流的重要交通枢纽。由于乌市特殊的地理气候条件,城市道路往往易发病害。本文通过乌市典型道路的病害调查,分析了乌鲁木齐道路病害的组成情况、高发类型及病害原因;进行结构强度调查,分析了龄期、结构类型等对乌市路面强度的影响;由芯样调查,分析了乌市服役路面的级配变化和空隙率情况。为后续建设工作提供了参考。     

沥青混凝土路面病害维修

半刚性路面基层、沥青混凝土路面的结构,强度和病害发展,分析了路面结构病害产生及维修.     

高速公路路基路面水毁病害处理

对延志吴高速公路路基路面水毁病害的类型及成因进行分析,详述了病害处治方案及方案选择的因素。     

京沪高速泰安段大修工程路面排水设计

路面排水是否通畅,对路面各种病害的产生和发展具有决定性因素,通过路表排水设计、沥青混凝土路面结构选型及抗渗性设计和路面结构内部防排水系统设计等方面完善路面排水系统,对高速公路的正常运行和行车安全具有重大意义。     

水泥混凝土路面病害发展过程研究

调查了多个项目的水泥混凝土路面病害发展过程,从材料、力学等方面分析了路面产生病害的原因及其产生病害的机理,提出了路面预防性养护的具体时机与方法,为水泥混凝土路面预防性养护和维修提供设计施工参考。     

沥青路面病害成因及坑槽修补工艺

随着使用年限的增长,受行车、气候、环境及超载等多方面的影响,沥青路面会出现龟裂、坑槽、车辙等路面病害,介绍了坑槽修补工艺。     

Development of distress condition index of asphalt pavements using LTPP data through structural equation modeling

Traditional pavement distress index such as the Pavement Condition Index (PCI) developed by U.S. Army Corps of Engineers determines coefficients of distresses based on subjective ratings. This study proposed an asphalt pavement distress condition index based on various types of distress data collected from the Long-Term Pavement Performance (LTPP) database through Structural Equation Modeling (SEM). The SEM method treated the overall distress index as a latent variable while various distresses were treated as endogenous and other influence factors such as age, layer thickness, material type, weather, environment and traffic, were exogenous observed variables. The SEM method modeled the contributions of various distresses as well as the influence of other factors on the overall pavement distress condition. Influences of age, layer thickness, material type, environment and traffic on the latent distress condition were in accordance with previous studies. Compared with previous attempts to model latent pavement condition index utilizing SEM method, more pavement condition measurements and influencing factors were included. Specifically, this study adopted the robust maximum likelihood estimator (MLR) to estimate parameters for non-normally distributed data and derived the explicit expression of latent variables with intercepts. A multiple regression prediction model was built to calculate an overall condition index utilizing those measured distress data. The established pavement distress index prediction model provided a rational estimation of weighting coefficients for each distress type. The prediction model showed that alligator cracking, longitudinal cracking in wheel path, non-wheel path longitudinal cracking, transverse cracking, block cracking, edge cracking, patch and bleeding were significant for the latent pavement distress index.     

Life cycle assessment of heated apron pavement system operations

Heated pavement systems (HPS) offer an attractive alternative to the cumbersome process of removing ice and snow from airport pavements using traditional snow removal systems. Although snow and ice removing efficiency and economic benefits of HPS have been assessed by previous studies, their environmental impact is not well known. Airport facilities offering public or private services need to evaluate the energy consumption and global warming potential of different types of snow and ice removal systems. Energy usage and emissions from the operations of hydronic heated pavement system using geothermal energy (HHPS-G), hydronic HPS using natural gas furnace (HHPS-NG), electrically heated pavement system (EHPS), and traditional snow and ice removal system (TSRS) are estimated and compared in this study using a hybrid life cycle assessment (LCA). Based on the system models assessed in this study, HPS application in the apron area seems to be a viable option from an energy or environmental perspective to achieve ice/snow free pavement surfaces without using mechanical or chemical methods. TSRS methods typically require more energy and they produce more greenhouse gas (GHG) emissions compared to HPS during the operation phase, under the conditions and assumptions considered in this study. Also, HPS operations require less energy and have less GHG emissions during a snow event with a smaller snowfall rate and a larger snow duration.     

Investigating effects of asphalt pavement conditions on traffic accidents in Tennessee based on the pavement management system (PMS)

Pavement maintenance is essential for ensuring good riding quality and avoiding traffic congestion, air pollution, and accidents. Improving road safety is one of the most important objectives for pavement management systems. This study utilized the Tennessee Pavement Management System (PMS) and Accident History Database (AHD) to investigate the relationship between accident frequency and pavement distress variables. Focusing on four urban interstates with asphalt pavements, divided median types, and 55 mph speed limits, 21 Negative Binomial Regression models were developed for predicting various types of traffic accident frequencies based on different pavement condition variables, including rut depth (RD), International Roughness Index (IRI), and Present Serviceability Index (PSI). The modeling results indicated that the RD models did not perform well, except for predicting accidents at night and accidents under rain weather conditions; whereas, IRI and PSI were always significant prediction variables in all types of accident models. Comparing the models goodness‐of‐fit results, it was found that the PSI models had a better performance in crash frequency prediction than the RD models and IRI models. This study suggests that the PSI accident prediction models should be considered as a comprehensive approach to integrate the highway safety factors into the pavement management system. Copyright © 2010 John Wiley & Sons, Ltd.     

Analysis of the effectiveness of control measures to mitigate road dust emissions in a regional network

The effectiveness of control measures to reduce road dust emissions is analyzed using a year’s data of road dust emissions collected with a mobile sampling platform and a survey of road maintenance practices in the Lake Tahoe Basin of Nevada and California US. Attributes such as sweeping practices, anti-icing, shoulder improvement, pavement condition, trackout, and abrasive material from road segments were analyzed with a feature subset selection algorithm. Street sweeping was found to be an effective means of controlling dust emissions from roads. Road dust from dirty tertiary roads served as a continuous source of suspendable material for adjacent high-speed roads in the winter time. To be most effective, emission control strategies require that not only primary roads, but all roads be swept after snow storms to recover applied abrasive material.     

沥青路面现场热再生技术解析

由于车辆荷载和一些不可抗拒的自然因素的作用,沥青路面经过一定年限的使用后就会出现部分的损伤和老化,因此为了不影响正常的交通秩序需要进行全方面的修缮,热再生沥青技术是重复利用废弃资源,保护环境和节约成本的重要技术,是道路保护的重要发展方向。     

橡胶沥青路面冬季施工温度控制措施研究

文章结合贵州省都匀市市政道路改造工程橡胶沥青路面施工实践,分析了冬季低温条件下橡胶沥青路面施工的影响因素,提出了冬季施工温度控制措施,并评述各项措施在工程应用中取得了良好的效果。     

水泥路面沥青加铺层反射裂缝成因及分析

文章针对目前旧水泥混凝土路面修复中沥青加铺层易产生反射裂缝的现象，结合沥青加铺层反射裂缝的扩展模式，分析其产生的成因，为防止或减缓沥青加铺层反射裂缝提供参考。     

Predicting asphalt pavement crack initiation following rehabilitation treatments

Prolongation of the service life of pavements requires efficient prediction of the performance of their structural condition and particularly the occurrence and propagation of cracking of the asphalt layer. Although pavement performance prediction has been extensively investigated in the past, models for predicting the cracking probability and for quantifying impacts of associated explanatory factors following pavement treatment, have not been adequately investigated in the past. In this paper the probability of alligator crack initiation following pavement treatments is modeled with the use of genetically optimized Neural Networks, The proposed methodological approach represents the actual (observed) relationships between of probability of crack initiation and the various design, traffic and weather factors as well as the different rehabilitation strategies. Data from the Long Term Pavement Performance (LTPP) Data Base and the Specific Pavement Study 5 (SPS-5) are used for model development. Results indicate that the proposed approach results in accurately predicting the probability of crack initiation following treatment; furthermore it provided information on the relationship between external factors and cracking probability that can help pavement managers in developing appropriate rehabilitation strategies.     

基于等效面积法的沥青路面预防性养护措施效果评价

本文基于安徽省高速公路路面历史性能数据,采用多元线性回归模型建立了预防性养护措施路面性能发展模型,评价了各预防性养护措施的适用性。针对实际情况采用"等效面积法"评价路面养护效益,考虑到预防性养护措施寿命较短,本文提出二次养护效益费用比的概念,对典型的预防性养护措施的实施效果进行了评价,并对影响养护效益的因素进行了分析。     

Evaluating the effects of climate change on road maintenance intervention strategies and Life-Cycle Costs

Climate change has the potential to impact long-term road pavement performance. Consequently, to maintain pavements within the same ranges of serviceability as before, current pavement maintenance strategies need to be re-assessed and, if necessary, changed. Changes in maintenance may lead to different agency costs and user costs as a consequence. This paper commences by defining an assessment procedure, showing how maintenance intervention strategies and Life-Cycle Costs (LCC) may be affected by future climate. A typical Virginia flexible pavement structure and anticipated climate change was used as an example. This example is believed to be representative for a great number of localities in the United States. A method using historical climatic data and climate change projections to predict pavement performance using Mechanistic-Empirical Pavement Design Guide (MEPDG) under current or future climate was introduced. Based on pavement performance prediction, maintenance interventions were planned and optimized. The maintenance effects of three treatments (thin overlay, thin overlay with an intermediate layer, and mill & fill) were considered. A Life-Cycle Cost analysis is reported that used binary non-linear programming to minimize the costs (either agency costs or total costs) by optimizing intervention strategies in terms of type and application time. By these means, the differences in maintenance planning and LCC under current and future climate can be derived. It was found, that for this simplified case study, pavement maintenance and LCC may be affected by climate change Optimized maintenance may improve resilience to climate change in terms of intervention strategy and LCC, compared to responsive maintenance.