试论沥青路面材料的再生工艺及专用机械设备的发展

沥青混凝土路面是目前国内外道路交通的主要面层结构,而沥青材料的热溶解特性,使沥青混合料能够较为容易地实现再生利用。作为节能减排和固废利用的重要组成部分,沥青混合料再生利用的工程规模及其技术进步也反映了一个国家或地区国民经济的发展和技术进步的总体水平。注重并优化沥青混凝土路面材料的再生工艺,并以符合技术条件的专用设备完成作业是路面材料高质量再生利用的前提和必要条件。     

水泥稳定砂砾就地冷再生工艺及其节能环保意义

道路损坏后路基和路面材料的再生利用不仅能够节约大量宝贵的筑路材料,而且具有重要的环境保护意义。采用冷再生技术将原有旧路面材料以专用机械作业方式进行就地再生,并将其作为水泥稳定砂砾摊铺在原有道路上并作为新铺道路的基础是实现上述理念的成功尝试。     

沥青路面再生过程中混合料路用特性的恢复分析

沥青路面材料的再生利用是道路交通领域固废利用及节能环保的重点项目。随着我国道路通车里程的快速增加和道路等级的不断提高,路面材料再生的质量要求也更为严格。如何达到相应的技术要求是衡量再生沥青混合料(RAP)性能质量的基本条件。在材料再生过程中,根据旧料中沥青的老化程度及矿料级配的变化等提出新料掺配的量化数据,以及专用机械设备的选取和配套作业工艺,是保证RAP用于道路铺筑质量的前提条件。     

沥青路面就地热再生关键技术探讨

公路路面养护是公路工程现代化管理中的重要组成部分,对公路运行能力产生重要影响。结合实际工程,对沥青路面就地热再生关键技术进行讨论,并对沥青路面就地热再生关键技术在公路路面养护中的应用进行分析,旨在提升公路施工综合管理能力,从而进一步提高公路综合性能。     

就地热再生技术在高速公路沥青路面养护中的应用

就地热再生技术作为我国道路材料回收的一项重要技术,能够将废旧沥青经简单处理后用于损伤路面的修复。基于泉州某高速公路沥青路面就地热再生工程实例,首先通过实地调研研判原有道路工程路面性能,结合混合料回收评价对再生沥青混合料材料进行组成设计;其次对施工所涉及到的各类质量控制要点展开分析;最后对热再生的质量做出检验评价。     

沥青路面材料再生过程的工艺优化

沥青路面日常养护和旧路改造工程中产生的大量路面材料的再生利用,具有显著的经济和环境保护的社会效益。研究和注重材料再生过程中的合理工艺和技术参数的优选,对于保证再生材料的路用质量和降低工程成本是十分必要的。     

泡沫沥青再生料稳定基层在干线公路路面整修工程中的应用研究

在高等级公路路面整修工程中,路面铣刨材料的再生利用一直是人们关注的课题。利用沥青发泡技术,将泡沫沥青与水、水泥和路面铣刨材料混合搅拌,形成性能介于柔性基层与半刚性基层之间的泡沫沥青再生稳定基层混合料,并用于陕西延安境内某干线公路路面整修工程中。实践证明,该基层具有技术指标高,经济效益显著的特点,在该大修工程中应用是可行的。     

废旧沥青混合料性能分析与评价方法研究

依托昆山市政道路升级改造工程,分别从旧路面材料中回收得到旧沥青和旧集料,系统运用宏观性能测试和微观组成测试,全面分析了旧沥青和旧集料材料性能和组成的变异性,为旧路面材料再生利用再生剂选取和新集料级配设计提供了理论指导依据。     

热再生沥青混合料在旧路改造应用中的试验与分析

通过添加再生剂和适当的配合比设计实现废旧沥青混合料的回收利用,经过热再生重新用于新建沥青混凝土路面的施工。试验结果表明：热再生混合料具有良好的路用性能,可以大规模用于新建路面材料的生产,既能降低原材料成本,也能减少废旧材料堆积占用的建筑、农业用地面积,具有很可观的经济价值和环保效应。     

沥青混凝土路面常见病害的处置及路面材料的再生利用

由于车辆对公路的反复碾压以及自然光候的长期作用,沥青路面必然会产生各种不同表现形式的破损。研究路面病害形成的机理及筑路材料的物化特性,进而以合理的工艺完成路面病害的处置,并对处置过程中产生的路面材料进行再生利用,不仅直接影响到公路的修复质量,节约大量宝贵的筑路材料,而且具有重要的环境保护意义。     

橡胶沥青技术在公路建设和养护中的应用

橡胶沥青作为一种新型的道路材料,具有降低路面噪音、提高行驶安全性与舒适性等优异性能。文章介绍了橡胶沥青的优点,分析了影响橡胶沥青及橡胶沥青混凝土质量的因素,并对橡胶沥青应用于公路建设和养护所存在的问题进行了探讨。     

浅析沥青路面性能衰减规律

文章通过对重庆成渝高速公路某段运行后的车流量及路面性能状况进行调查,分析其路面病害状况及产生的原因,研究其路面衰减的规律,并针对各个阶段的路面性能,制定出适宜的养护方案。     

浅议公路路面裂缝的治理措施

文章分析了沥青公路路面出现裂缝的原因,从施工技术、养护管理、材料特征、公路排水性能及路基设计等方面提出了针对性的解决方法及预防路面产生裂缝的具体措施。     

Traffic modelling in system boundary expansion of road pavement life cycle assessment

This paper uses a case study of a UK inter-urban road, to explore the impact of extending the system boundary of road pavement life cycle assessment (LCA) to include increased traffic emissions due to delays during maintenance. Some previous studies have attempted this but have been limited to hypothetical scenarios or simplified traffic modelling, with no validation or sensitivity analysis. In this study, micro-simulation modelling of traffic was used to estimate emissions caused by delays at road works, for several traffic management options. The emissions were compared to those created by the maintenance operation, estimated using an LCA model. In this case study, the extra traffic emissions caused by delays at road works are relatively small, compared to those from the maintenance process, except for hydrocarbon emissions. However, they are generally close to, or above, the materiality threshold recommended in PAS2050 for estimating carbon footprints, and reach 5–10% when traffic flow levels are increased (hypothetically) or when traffic management is imposed outside times of lowest traffic flow. It is recommended, therefore, that emissions due to traffic disruption at road works should be included within the system boundary of road pavement LCA and carbon footprint studies and should be considered in developing guidelines for environmental product declarations of road pavement maintenance products and services.     

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.     

Comparative life-cycle assessment of conventional (double lane) and non-conventional (turbo and flower) roundabout intersections

This research studied and compared different construction techniques for the road subgrade, embankment and pavement of different types of roundabout intersections in order to assess their environmental sustainability. A Life Cycle Assessment (LCA) was carried out on double lane, turbo- and flower roundabouts.We considered virgin materials and reclaimed asphalt pavement (RAP) for the pavement construction. Also the environmental effects due to in situ lime stabilization of fine-grained soils were assessed in order to reduce the use of virgin material in road subgrades.The use of reclaimed asphalt pavement (RAP) can lead to a significant reduction in pollutant emissions and energy consumption (especially due to the lesser material transport) – though with a slightly different impact according to the different percentages employed – compared to the pavements constructed with virgin materials. The same consideration can be made for fine soils with in situ lime stabilization: on the one hand, the technique allows to improve significantly the mechanical properties of soils which would be otherwise dumped and, on the other, to provide considerable environmental benefits. The life cycle assessment of the pavement was carried out with the help of the PaLATE software (by comparing different maintenance scenarios) while emissions and energy consumption in the use phase at intersections were evaluated by means of closed-form models (to estimate vehicle delays and speeds of vehicles) and the COPERT software.Finally, the generalized costs covered in the whole life cycle of roundabouts (i.e. sum of construction, maintenance and environmental costs) were assessed and associated to the different construction options.     

A comparative study of the emissions by road maintenance works and the disrupted traffic using life cycle assessment and micro-simulation

Life cycle assessment is being accepted by the road industry to measure such key environmental impacts as the energy consumption and carbon footprint of its materials and laying processes. Previous life cycle studies have indicated that the traffic vehicles account for the majority of fuel consumption and emissions from a road. Contractors and road agencies are looking for road maintenance works that have the least overall environmental impact considering both the roadwork itself and the disrupted traffic. We review life cycle assessment studies and describe the development of a model for pavement construction and maintenance, detailing the methodology and data sources. The model is applied to an asphalt pavement rehabilitation project in the UK, and the micro-simulation program VISSIM is used to model the traffic on that road section. The simulation results are fed into a traffic emissions model and emissions from the roadwork and the traffic are compared. The additional fuel consumption and emissions by the traffic during the roadwork are significant. This indicates that traffic management at road maintenance projects should be included in the life cycle assessment analysis of such work.     

浅析高等级公路沥青路面预防性养护对策

文章分析了近年来国内外沥青路面预防性养护现状。根据道路结构状况与时间曲线,提出了预防性养护对策,包括选择恰当的路面、确定最佳预防性养护时机等,并对预防性养护技术进行了分析,以确定最佳的预防性养护方案。     

旧水泥砼路面加铺沥青面层结构技术经济分析

文章结合某高速公路水泥混凝土路面大修情况,介绍不同路段采用不同的加铺沥青层设计方案,并就路面维修建设费用和使用寿命间的经济关系进行分析和研究,为同类维修项目提供参考。     

多年冻土区公路路面路基管理系统设计

我国多年冻土地区公路受气温及水分变化等影响,公路病害发生严重。为了使公路养护部门合理利用资金,最大限度避免冻土病害,有必要建立冻土区公路路基路面评价预测系统。文章介绍了冻土区公路路基的评价指标和评价方法。在常规路基路面评价预测的方法上,还使用了马尔可夫等预测方法,以适合冻土区公路路面破坏机理复杂、影响因素多的实际情况。