Life cycle assessment (LCA) tools have been used by governments and city administrators to support the decision-making process toward creating a more sustainable society. Since LCA is strongly influenced by local conditions and may vary according to various factors, several institutions have launched cooperation projects to achieve sustainable development goals. In this study, we assessed the potential environmental enhancements within the production of road materials applied to the road network of Münster, Germany. We also compared traditional pavement structures used in Münster and alternative options containing asphalt mixtures with larger amounts of reclaimed asphalt pavement (RAP). Although the case study was conducted in Münster, the data collected and the results obtained in this study can be used for comparison purposes in other investigations. In the analysis, we considered all environmental impacts from raw material extraction to the finished product at the asphalt plant. Two environmental indicators were used: non-renewable cumulative energy demand (nr-CED) and global warming potential (GWP). The results show that using RAP increases the consumption of energy but potentially decreases the environmental impacts in terms of the nr-CED and GWP associated with the production of asphalt materials.

This study used a cradle-to-cradle Life Cycle Assessment (LCA) approach to evaluate the environmental potentials of urban pavements. For this purpose, the urban road network of the City of Münster (Germany) was selected as the case study, and comprehensive data for several phases were collected. The entire road network is composed of flexible pavements designed according to specific traffic loads and consists of main roads (MRs), main access roads (MARs), and residential roads (RSDTs). Asphalt materials, pavement structures, and maintenance strategies are predefined for each type of road and are referred to as “traditional” herein. Some pavement structures have two possible maintenance strategies, denoted by “A” and “B”, with distinguished periods of intervention. To evaluate the impact of using recycled materials, we considered alternative pavement structures composed of asphalt materials containing a greater amount of reclaimed asphalt pavement (RAP). The study was carried out considering analysis periods of 20, 50, 80, and 100 years and using two indicators: non-renewable cumulative energy demand (nr-CED) and global warming potential (GWP). The results show that the use of higher amounts of RAP can mitigate negative environmental impacts and that certain structures and maintenance strategies potentially enhance the environmental performance of road pavements. This article suggests initiatives that will facilitate the decision-making process of city administrators to achieve more sustainable road pavement constructions and provides an essential dataset inventory to support future environmental assessment studies, particularly for European cities.

Several studies evaluated the feasibility of using residues to compose asphalt mixtures. However, the demand for treatments are often neglected in determining the environmental impacts. This study aims to elucidate the decision-making process over the application of residues (e.g., red mud and fly ash) to produce asphalt mixtures. For comparison purposes, limestone and dolomite are used as reference fillers. The cradle-to-gate approach is applied within three scenarios. In the first scenario, the treatment of the residues is included in the modelling, the second excludes treatment, and the third scenario evaluates the environmental impacts of the residues deposited in landfills. To perform the analysis, indicators such as Global Warming Potential, Acidification, and Cumulative Energy Demand are applied. The results show that the treatment provided to the residues strongly influences the environmental impacts of the production of asphalt mixtures and may be crucial to define the feasibility of the residues application.

Private participation in roads revived strongly in transition and developing countries between 2005 and 2008, growing during the period from US$6.2 billion to US$16.4 billion a year, a new historic peak. However, in view of the recent global financial crisis, there has been some retraction of private financing resulting in an investment of US$15.8 billion in 2009. Driving policy-makers' renewed interest in attracting private financing for roads is the need for greater investments to keep road networks in an acceptable condition and carry out social and economic expansion plans in a context of public budget constraints. An analysis is presented of recent trends in road projects with private participation in developing and transition economies, in view of the policies and models adopted by these countries. A procedure for estimating the minimum toll rates required to attract private investors is also presented.