冷再生技术在国道324线岑容公路中的应用

目前,冷再生技术广泛用于旧路的维修、改造及升级中。文章结合国道324线岑溪一容县一级公路沥青砼路面大修工程实践,介绍了路面基层冷再生技术及施工工艺。从实施效果来看,冷再生技术有保证质量、施工速度快、工程造价低和节能环保等优点,是一种较实用的公路沥青路面大修养护新的技术。     

沥青路面就地冷再生技术原理与造价对比分析

本文结合东营地区农村公路养护工程中沥青路面就地冷再生技术应用情况,从工程实际出发,阐述了施工过程中沥青路面就地冷再生的技术原理、稳定材料的选用和应用成本的对比分析,以期为国内同行业公路养护工程起到借鉴作用。     

旧沥青路面就地冷再生施工工艺在公路改造中的应用

旧沥青路面冷再生施工技术充分利用了原本需废弃的沥青混合料,节约了资源,减少了材料成本投入,具有广阔的应用前景。文章基于旧沥青路面再生技术的研究现状,分析了不同旧沥青路面再生技术在公路改造工程中的适用范围,论述了就地冷再生技术的选用原则与施工技术方法,并结合某二级公路改造工程实例,阐述了旧沥青路面就地冷再生施工工艺的具体应用,以供类似工程参考。     

公路养护工程四新技术应用分析——以常州市普通国省公路养护工程为例

现阶段我国国民经济增长态势良好,公路交通运输量也随之持续增长,为了保持公路各项基础设施的良好运营状态,以常州市普通国省公路养护工程为例,根据公路养护控制的基本要求,分析水稳就地冷再生、半柔性灌浆复合路面、渗固磨耗层施工、CCA抗裂磨耗层沥青混合料等利用新技术、新工艺、新材料、新设备的四新技术在养护工程中的应用,以此为其他公路养护工程提供参考。     

水泥就地冷再生技术应用与实践探讨

文章结合县道187线K0+000～K16+300段路面大修工程实例,介绍了水泥就地冷再生技术的施工原理,探讨了采用就地冷再生技术进行公路大修、改扩建及日常养护工作的关键性技术措施。     

水泥稳定碎石冷再生技术在公路路面改造中的应用

文章以国道G324线岑溪至容县（容县段）一级公路路面改造工程为例,总结水泥稳定碎石冷再生施工工艺,分析其应用的经济效益与社会效益,并结合工程应用的效果,评价稳定碎石冷再生技术是一种经济合理的路面改造方式,具有较高的应用价值.     

泡沫沥青冷再生技术在公路养护中的应用

随着我国国民经济的迅速增长,公路工程快速发展,在一定程度上推动了公路沿线城市的进步,为人民生活出行提供极大的便利.现阶段,由于公路服务年限的延长,部分道路进入养护维修阶段,而泡沫沥青冷再生技术作为一种环保和经济两者兼顾的养护方式目前已经得到广泛地推广、应用.为此,本文主要围绕泡沫沥青冷再生技术在公路养护中的具体应用进行探讨,希望能够促进我国公路养护工作水平的提高.     

沥青路面再生技术在公路养护工程的应用研究

在公路建设施工项目中要充分发挥公路的性能,需要对养护工作予以重视,对公路性能的修复起到了重要的作用。其中就地冷再生技术具有工程造价低、施工安全、有效节约资源、施工快捷等优势,针对沥青公路路面养护问题,得到了广泛的应用。本文就其应用进行分析和探讨。     

海母冷再生技术在路面施工中的应用

在公路路面养护施工中,传统的做法是把破损的旧路面进行修补,当路基强度不够时,可以全部挖除旧路面以及旧的结构,然后重做公路的基层和面层。但此种方法的不足之处在于工程成本较高,且无形中会延长施工工期,也会对环境造成污染,给行人的正常出行带来了很大的不便。为了有效解决道路改建施工中存在的问题,经过研究与实践,采用海母冷再生技术,为公路的施工改建提供了一个新方法具体探讨了海母冷再生技术在路面施工中的应用。     

乳化沥青厂拌冷再生节能效益量化与评价

通过对国内外乳化沥青厂拌冷再生养护工程技术进行分析,根据基础数据和理论推导确定了养护工程施工期间四个环节的能耗计算方法,并计算了养护工程能耗评价指数。结合两项依托养护工程施工设备的现场监测数据以及基础参数,量化了乳化沥青厂拌冷再生和普通沥青混凝土两项养护技术的各环节的直接能源消耗以及养护工程能耗指数。通过对研究所得到的量化数据和乳化沥青厂拌冷再生节能效益进行了系统的对比分析,得到了原材料和混合料加热是能耗主要环节,乳化沥青厂拌冷再生具有很好的节能效益等重要结论,为国内外同行开展相关研究提供了参考。     

道路改建中路基石方爆破施工技术

文章以309国道武安段改建工程为例,简要介绍了石方爆破技术的施工工艺、施工方法及施工中应注意的问题,进而说明了石方爆破技术在道路改建中的重要性。     

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.     

The overall effects of road works on global warming gas emissions

Road characteristics influence the amount of pollution generated by traffic. They govern the rolling resistance, which includes: the viscoelastic behaviour of the pavement structure, surface texture, and profile unevenness. Road works are performed on a periodic basis to maintain these characteristics at proper levels of service (e.g. safety, comfort, and noise). While such works produce additional pollution (due to congestion around worksites or extra fuel consumption along the detour route), they still result in less pollution over the long term. This article assesses the balance between an increase in gas emissions during road works and the reduction in emissions from traffic once the works are completed. It is demonstrated that when road works are introduced to correct longitudinal profiles, rather than texture, the emissions benefit is substantial.     

A novel dynamic segmentation model for identification and prioritization of black spots based on the pattern of potential for safety improvement

Road segmentation is one of the most important steps in identification of high accident-proneness segments of a road. Based on the ratio of the Potential to Safety Improvement (PSI) along the road, the objective of the paper is to propose a novel dynamic road segmentation model. According to the fundamental model assumption, the determined segments must have the same pattern of PSI. Experimental results obtained from implementation of the proposed method took four Performance Measures (PMs) into consideration; namely, Crash Frequency, Crash Rate, Equivalent Property Damage Only, and Expected Average Crash Frequency with Empirical Bayes adjustment into the accident data obtained from Highway 37 located between two cities in Iran. Results indicated the low sensitivity of the method to PMs. In comparison with the real high accident-proneness segments, identified High Crash Road Segments (HCRS) obtained from the model, demonstrated the potential of the method to recognize the position and length of high accident-proneness segments accurately. Based on the road repair and maintenance costs limitation index for safety improvement, in an attempt to compare the proposed method of road segmentation with conventional ones, results demonstrated the efficient performance of the proposed method. So as to identify 20 percent HCRS located on a read, the proposed method showed an improvement of 38 and 57 percent in comparison with the best and worst outcomes derived from conventional road segmentation methods.     

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。     

我国公路桥梁安全状况及对策

文章针对目前我国桥梁安全现状,分析桥梁事故发生的原因,指出解决桥梁安全问题是一个系统工程,须由政府部门和建设、养护、使用单位共同努力才能奏效。     

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.     

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。     

Optimization of horizontal alignment geometry in road design and reconstruction

This paper presents a general formulation for optimization of horizontal road alignment, composed of tangential segments and circular curves suitably connected with transition curves (clothoids). It consists of a constrained optimization problem where the objective function is given by a line integral along the layout. The integrand is a function representing the cost of the road going through each point and, by considering different costs, a wide range of problems can be included in this formulation. To show it, we apply this methodology to three different situations. The two first cases are related with the design of a new road layout and used to solve a pair of academic examples. The third problem deals with the improvement of a road adapting the old path to current legislation, and it is solved taking as case study the reconstruction project for a regional road (NA-601) in the north of Spain.