沥青砼转运-摊铺工艺在河龙高速公路的试验研究

通过在河龙高速公路沥青路面摊铺过程中采用摊铺机直接摊铺作业和采用转运—摊铺工艺(转运车-摊铺机联合施工)作业的试验路面效果对比,实验研究结果表明采用转运—摊铺施工工艺是消除温度离析、减轻骨料离析、提高路面平整度的有效手段。     

沥青路面抗滑表层的设计与对比分析

结合国内外最新研究成果,针对某试验路的特点,选择确定了试验路采用的3种抗滑表层混合料类型以及混合料采用的设计方法和技术指标。继而全面对比分析了3种抗滑表层在级配、沥青用量波动下各混合料体积参数的变化以及抗车辙与水损害性能。试验结果表明:当级配、沥青用量发生波动时,AK 13A对混合料体积参数影响最大,其次为Superpave 13,AC 13K最小;在路用性能方面AC 13K较AK 13A、Superpave 13均有不同程度的改善与提高。试验路检测结果表明:AC 13K与Superpave 13使用性能均达到或超过规范的要求,具有良好的平整度、防渗水能力;AK 13A尽管具有较大构造深度,但防渗水能力较差。这些为选择合适的抗滑表层提供了可靠依据。     

沥青混合料转运车对施工质量的改善效果和应用前景分析

本文结合沥青混合料转运车在盐通高速公路上的应用情况,对使用和未使用沥青混合料转运车的路面离析状况进行调查、对比。通过现场的应用以及对调查数据的分析,对其在减轻沥青混合料离析、提高路面施工质量方面的作用作出了准确评价,并对其应用前景进行了分析。     

Life cycle assessment of bituminous pavements produced at various temperatures in the Belgium context

Bituminous mixture is the premier material for road construction in Belgium. Innovative technologies to improve energy efficiency of pavement constructions are necessary. Warm mix asphalt may provide significant energy savings to the asphalt industry, but the environmental impact of the total life cycle has to be investigated. The use of additives may counteract the reduced environmental impact due to energy savings. This paper presents the results of an environmental impact assessment of four wearing course test sections. Using life cycle assessment, hot mix asphalt is compared to a cold asphalt mix with emulsion and warm mix asphalt with two types of additives: a synthetic zeolite and an organic Fischer–Tropsch wax. Neither hot nor warm mix asphalt could be preferred based on the results of this study, because the additive has a major influence on the environmental results. It was seen that the production of bitumen, the transport and energy in order to generate heat mainly contribute to the total environmental impact. The results from the sensitivity analyses show that the total environmental impact of the life of the pavement can vary significantly based on the choice of the specific data source and service life.     

The limits of partial life cycle assessment studies in road construction practices: A case study on the use of hydrated lime in Hot Mix Asphalt

Extensive published literature shows that hydrated lime improves Hot Mix Asphalt (HMA) durability. Its impact on the environmental impact of HMA has not been investigated. This paper presents a comparative Life Cycle Assessment (LCA) for the use of HMA without hydrated lime (classical HMA) and with hydrated lime (modified HMA) for the lifetime of a highway. System boundaries cover the life cycle from cradle-to-grave, meaning extraction of raw materials to end of life of the road. The main assumptions were: 1. Lifetime of the road 50 years; 2. Classical HMA with a life span of 10 years, maintenance operations every 10 years; 3. Modified HMA with an increase in the life span by 25%, maintenance operations every 12.5 years. For the lifetime of the road, modified HMA has the lowest environmental footprint compared to classical HMA with the following benefits: 43% less primary total energy consumption resulting in 23% lower emissions of greenhouse gases. Partial LCAs focusing only on the construction and/or maintenance phase should be used with caution since they could lead to wrong decisions if the durability and the maintenance scenarios differ. Sustainable construction technologies should not only consider environmental impact as quantified by LCA, but also economic and social impacts as well. Avoiding maintenance steps means less road works, fewer traffic jams and hence less CO₂ emissions.     

绿色道路:路面可持续性评价系统

绿色道路是评价路面设计和施工过程相关的可持续性发展的一种建议标准。该系统依据可持续发展的实践性为道路工程打分,通过得分的高低来评价工程的可持续性。充分完善的绿色道路系统具有以下内容和功能:1)鼓励更多道路工程尝试可持续性的实践;2)为道路可持续性评价提供一种标准和方法;3)使工程设计更优;4)使业主单位能评判道路工程的优劣。绿色道路评价系统通过6大类的54个评分项完成对道路工程的评分,是发展道路可持续性设计的可靠系统。     

Superpave混合料施工技术

Superpave技术与传统的马氏技术是两种不同的沥青混合料设计方法。根据推广应用Superpave技术取得的经验和测试数据,简要介绍Superpave施工技术的控制要点和必须注意的若干技术问题。     

热拌薄层罩面力学响应分析

本文利用ABAQUS有限元软件对原路面加铺罩面层后的应力响应进行了分析,考察了不同罩面厚度以及超载作用下的剪应力响应,认为水平力的作用将对罩面层表面材料提出更高的抗剪要求,罩面层厚在1.5~2.5 cm范围内其剪应力变化不大,经综合考虑,热拌罩面层厚2 cm是经济而且合适的。     

沥青混合料禁区路用性能研究

对禁区下、禁区偏下、禁区中间、禁区偏上、禁区上以及规范中的AC-16中值6种级配的沥青混合料进行路用性能试验与分析,得出:禁区的规定是不必要的,通过禁区中间级配的路用性能最优.     

沥青路面压实影响因素分析

沥青路面压实可以减小沥青混合料空隙率,得到平整密实的路面.分析了影响沥青路面压实质量的主要因素,即沥青混和料、温度、施工工艺和碾压设备,并从这4个方面,就如何提高沥青混凝土路面压实质量提出了几点看法,以确保路面压实的质量.