二灰碎石基层冷再生施工技术应用

利用旧路面基层获取铣刨料,添加新鲜骨料、结合料后进行再生混合料级配组成及配合比设计。利用二灰比、集料含量与28d劈裂强度关系方程,对配合比进行验证。着重阐述了混合料拌和工艺及连续式拌和设备成品料仓的改进。在拌和、摊铺、压实、养生等工艺上对再生混合料的施工提出控制要点及质量控制措施。     

Modelling of the pavement acoustic longevity in Hong Kong through machine learning techniques

Traffic noise emission has long been a pervasive environmental and ecological problem, especially in the metropolitan cities with large-scale traffic network and high population density. Low noise road surface (LNRS) has been actively developed and applied as an effective measure to maintain the quieter environment of mobility service system. However, when LNRS is applied for noise abatement, the relationship between the acoustic performance and degradation of pavement has not been fully understood yet. To this end, this study aims to model the acoustic longevity of asphalt pavement as a function of the thickness, binder content, maximum aggregate size, and air void content of the pavement surface, as well as vehicle speed based on the long-term tyre-road noise data collected from 270 asphalt pavement sections in Hong Kong. Two machine learning techniques, namely artificial neural networks (ANN) and support vector machines (SVM), were employed and compared. It was found that both ANN and SVM could successfully model the pavement acoustic performance with acceptable model performance metrics. A case study showed that the ANN model was more aligned with the aging mechanisms of porous road surface, but the SVM model showed better training performance. The predicted acoustic deterioration rates of the porous surface case varied from −0.1 to 0.28 dB(A)/month rather than keeping a constant linear increasing trend, depending on pavement ageing periods and vehicle speed levels. The two-dimension sensitivity analysis (2D-SA) revealed the relative importance of pavement age and vehicle speed in controlling the acoustic performance.     

Use of infrared thermography for assessing HMA paving and compaction

The assessment of paving and compaction temperatures effect on Hot Mix Asphalt (HMA) properties has been the subject of various researches. The present study aims to build upon these researches, by investigating the effectiveness and practicality of infrared thermography (IRT) as an emerging technology to assess HMA paving and compaction. For this purpose a field experiment was performed using a thermographic system to investigate the impact of the temperature in a paving project where two different types of HMA were used. The recorded mat surface temperatures are used effectively for the identification of temperature differentials, as well the detection of pavement defects. In addition, density-growth curves are developed for the specific mixtures and compaction pattern being used. IRT data is further analyzed for the development of simple HMA cooling models, providing a quick and efficient means to estimate the compaction time. More details and discussion are outlined in the paper.     

两种温拌沥青混合料路用性能的对比试验研究

文章中作者选用两种温拌沥青混合料添加剂进行室内试验,与同级配热拌沥青混合料进行对比。结果表明,两种温拌剂均可降低沥青混合料生产温度,同时高温稳定性、水稳定性基本与热拌沥青混合料相当。     

露石水泥混凝土路面施工工艺研究

文章通过对露石水泥混凝土施工工艺进行室内试验研究,得出确定合适的缓凝剂喷洒遍数和喷洒、冲洗的时间和范围;介绍露石混凝土中粗集料的含量对露石度的影响和控制方法,为露石水泥混凝土路面的设计提供借鉴。     

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.     

沥青路面抗滑性能影响因素识别研究进展

沥青路面作为公路建设的重要内容,其抗滑性能是道路安全问题的核心,探究其影响因素可以为提高路面抗滑性能提供依据。国内外学者对此做了大量研究,也取得了相应的进展。本文对国内外的研究成果进行了系统的归纳总结,将公路沥青路面抗滑性能影响因素分为了沥青混合料的材料特性、环境因素、车辆特性3个主要方面,其中在沥青混合料的材料特性方面,研究认为集料的结构特性与混合料配合比对抗滑性的影响较大;环境因素方面,研究认为温度对于抗滑性的影响较大;车辆特性对抗滑性的影响方面,研究认为主要体现在轮胎特性与荷载方面。此外随着行车速度的增加,路面的抗滑性能呈现降低趋势。     

废弃水泥混凝土板基层试验室成型方法研究

水泥混凝土道路改建时形成的废弃混凝土块的有效利用是一个亟待解决的问题。文章通过对废弃混凝土再生集料的加工和性质的检测,采用水泥做结合料,在试验室利用不同成型方法成型半刚性基层,检验其力学性能,得出振动压实成型方法更适用废弃混凝土再生集料基层的结论。同时也证明了,采用水泥做结合料进行稳定的废弃混凝土再生集料基层能够满足现行规范高等级公路基层的指标要求,是废弃混凝土再生利用的一个有效途径。     

机场沥青道面修补材料合理压实温度探讨

文章采用马歇尔试验方法,在不同温度下成型试件,测试马歇尔体积参数的变化,分析温度对SMA沥青混合料毛体积密度和空隙率的影响,并根据机场沥青道面修补材料空隙率3%～5%的要求,探讨机场沥青道面修补材料的合理压实温度。     

大粒径ATB水稳定性评价方法研究

沥青稳定碎石基层在我国沥青路面中的应用越来越广泛,其路用性能的优劣对路面使用寿命影响很大。文章通过浸水马歇尔试验和冻融劈裂试验,对不同级配大粒径沥青稳定碎石混合料的水稳定性进行了对比试验研究。与浸水马歇尔试验相比,冻融劈裂试验更能体现不同级配混合料水稳定性的差异,并能较好地模拟混合料水损坏过程,是评价大粒径沥青稳定碎石混合料水稳定性的优选方法。     

沥青路面冷再生沥青混合料配合比设计研究

冷再生沥青混合料施工技术是一种节能环保的公路路面修复技术,不但可以有效减少石料、沥青、水泥的需求量,降低工程成本,减少了资源浪费,并且与热再生技术相比可以有效降低CO2排放量。配合比设计是影响冷再生沥青混合料质量的关键因素,本文以某公路沥青路面修复工程为例,对沥青路面冷再生沥青混合料配合比进行研究,以加强冷再生沥青混合料质量控制。     

祥周至龙邦公路路面大修施工质量控制

文章以祥周至龙邦二级公路路面大修工程为例,介绍采用旧路油面层和水泥稳定碎石基层进行再生利用的大修施工方案,从细粒式沥青混凝土上面层、沥青碎石再生料下面层（AM-16）、沥青碎石封油层、水泥稳定碎石再生基层等方面阐述了路面各结构层施工技术要求和质量控制要点。     

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.     

冷再生技术在公路养护工程中的探索与应用

冷再生技术是一种新的施工工艺,其原理是将原路面及基层破碎后作为集料,再辅以水泥、沥青、石灰等稳定剂和一定数量的集料,经拌和、整平、碾压等工艺,重新处理后而形成新的路面基层,从而可使原路面功能得以恢复。     

碎石化沥青加铺层的高温稳定性研究

文章以南宁-梧州二级公路路面大修改造工程为依托,介绍了旧混凝土路面碎石化沥青加铺层的技术特性及作用机理,阐述了Superpave沥青混合料矿料级配设计方法,并根据沥青混合料分形级配理论,探讨了粗集料用量对沥青混合料高温稳定性能的影响。结果表明：增加了26.5 mm1、9 mm的粗集料用量的AC-20沥青混合料具有较好的高温稳定性能。     

The effect of time on acoustic durability of low noise pavements – The case studies in Poland

The tyre/road noise depends on type and speed of vehicles and on the characteristics of road pavement. Vehicle traffic load and weather conditions lead to significant changes in the characteristics of the materials used to build the wearing course. This applies especially to road pavements with the increased void contents. Clogging of the pores, changes in the characteristics of the binder and the damage to the wearing course influence changes in the acoustic properties of the road pavement over time. The article presents the results of the studies on noise level carried out in 2011 and 2014 by the Statistical Pass-By method (SPB) on porous asphalt concrete (PAC), very thin asphalt concrete (VTAC) and stone mastic asphalt (SMA). The wearing courses with the increased void contents immediately after building constitute a very advantageous solution compared with traditional road pavements (dense asphalt concrete, stone mastic asphalt). However, the unfavourable location of the road with porous wearing course, lack of systematic cleaning of porous layers or inappropriate maintenance methods in winter lead to the loss of the acoustic durability of low-noise pavements within a few years of their exploitation.     

公路隧道环保型温拌沥青混合料性能研究

文章从沥青性能、混合料路用性能、环保性能等方面对温拌沥青混合料（WMA）与热拌沥青混合料（HMA）进行对比试验研究,结果表明：与HMA相比WMA可以降低拌和、成型温度约20℃～25℃,其路用性能满足技术规范要求,具有良好的环保性能。并结合工程实例,评述了温拌沥青混合料在公路隧道工程中的应用效果。     

广西沥青路面施工标准化与质量控制技术研究

为避免沥青路面出现车辙等早期损坏,文章结合广西自然条件,从集料加工生产与质量控制、沥青混合料级配优化设计、沥青路面施工工艺等方面开展沥青路面施工标准化与质量控制技术研究,提出在源头控制集料加工指标,采用均匀防离析-骨架稳定密实型沥青中、下层混合料和优化的抗滑表层沥青混合料,实施施工过程标准化管理,以有效提升机械化施工效率和路面施工质量。     

彩色沥青路面的应用与发展

彩色沥青路面作为功能性路面和景观道路,已引起了人们的广泛关注与重视.文章结合国内外彩色沥青路面的发展现状,介绍了彩色沥青路面的种类、设备、相关指标标准、配合比设计及施工工艺等,指出了彩色沥青路面目前存在的主要问题,为开展相关研究提供参考.     

热拌沥青混合料降温规律试验研究

文章通过室内试验,对不同摊铺厚度及环境温度下的不同基质沥青、级配类型的热拌沥青混合料的降温情况进行研究,得出了热拌沥青混合料的降温规律,为热拌沥青混合料的室内试验及生产施工控制提供参考依据。