This study aims to quantify the health and environmental damages of emissions released by pavement management activities in Ontario. The construction, maintenance, and rehabilitation of pavement results in greenhouse gases and pollutants which have significant impacts on human health and the environment. Traditional lifecycle costing methods used in pavement management systems do not account for the cost of these impacts. Marginal damages which relate atmospheric releases to economic cost can be applied by decision-makers to understand the damages of activities (such as pavement management) but require careful consideration of underlying factors. Marginal damages from various methods across the literature were adjusted for application in this study. The present work quantified environmental costs for the construction and lifecycle maintenance of five pavement design alternatives based on emissions of carbon dioxide and four air pollutants. Concrete roads were found to have the highest environmental costs (equivalent to 77% of agency costs) whereas asphalt roads rehabilitated with Cold-in-Place recycling had the lowest environmental costs due to the reduction in raw materials used. For the asphalt road alternatives, environmental costs were equivalent to 35% of agency costs. Future work will address limitations in data availability and additional design types. These findings provide insight for further integration of externalities in pavement management systems including of noise, user costs, and use phase emissions.

This Interim Technical Bulletin recommends procedures for conducting Life-Cycle Cost Analysis (LCCA) of pavements, provides detailed procedures to determine work zone user costs, and introduces a probabilistic approach to account for the uncertainty associated with LCCA inputs.

This synthesis will be of interest to pavement designers, maintenance engineers, and other concerned with selection of pavement designs and pavement rehabilitation alternatives. Information is presented on how life-cycle can be used to select the alternative that is least expensive over time.

A pavement performance and life-cycle cost evaluation of a polymer modified asphalt cement Styrelf) has shown technical advantages and cost savings. The evaluation involved seven Ontario asphalt concrete pavements, representing various traffic and climatic conditions, placed between 1987 and 1992. A surface distress survey was completed for representative sections with the polymer modified asphalt cement and control sections with conventional asphalt cement. Rut depth was determined from transverse profiles. The surface distress information was analyzed using the American Public Works Association PAVER procedures to determine the Pavement Condition Index for each section. This information was used to model the pavement condition through a 30 year analysis period. Life-cycle costing was completed to determine the present worth of the construction, maintenance and rehabilitation costs. The pavement performance modelling indicated the polymer modified asphalt cement extended the pavement service life by about 4 to 6 years compared to conventional asphalt cement. This service life extension was confirmed by testing representative asphalt concrete cores in the Nottingham Asphalt Tester, which indicated improved rutting resistance and increased fatigue life. The results of the life-cycle cost analysis showed significant life-cycle cost savings for pavements incorporating polymer modified asphalt cement mixes. For the covering abstract of this conference see IRRD number 872978.

These guidelines apply to the life cycle cost analysis (LCCA) of high-volume roadways, all freeways & 400 series highways, and all concrete pavements in Ontario. Information is included on the nature of LCCA; the components of LCCA including discount rate, service life & activity timing, cost factors, and deterministic versus probabilistic LCCA; alternative bid criteria in the process for freeway paving contracts; and the Ministry of Transportation LCCA procedure for flexible & rigid freeway pavements. Recommended service lives and typical preventive & rehabilitation strategies & timings for the two main freeway designs (deep strength asphalt pavement and doweled jointed plain concrete pavement) are summarized in the guidelines. Appendices include example calculations.