The use of life-cycle cost analysis (LCCA) as a decision-making tool in pavement design and the analysis of competing alternatives is recommended by FHWA. However, dependence on deterministic LCCA raises issues about the accuracy of input information because of the degree of construction price volatility found in the underlying commodities used in pavements. Stochastic LCCA has been shown to produce superior results when used at the new pavement design or network level and is suggested for transportation use by FHWA. However, no project-level tools exist to facilitate use of a stochastic approach to evaluate pavement preservation treatment. This paper proposes a practical stochastic LCCA model on the basis of equivalent uniform annual cost, specifically to compare pavement preservation treatment alternatives. The paper explores statistical LCCA techniques that expose inherent uncertainties to identify and quantify the risk of commodity price volatility. The proposed methodology enhances a pavement engineer's ability to address budget issues, mitigate risk, and justify pavement preservation treatment decisions. Underlying commodity price volatility in pavement treatment costs can be modeled effectively with stochastic LCCA.

1Classic engineering economic theory was developed to furnish the analyst a tool to 2 compare alternatives on a basis of life cycle cost (LLC). However, tools used to apply 3 theory to transportation focus on new construction projects with relatively long service 4 lives. These tools do not accurately model the economic aspects of short-lived 5 alternatives such as those that pavement managers must evaluate when seeking the most 6 cost effective pavement preservation treatment. The field of pavement preservation seeks 7to "keep good roads good" and hence, pavement preservation treatments are applied to 8 extend the functional service life of the underlying pavement. No significant research has 9 been done to quantify the actual service lives of the pavement preservation treatments 10 themselves nor a model been furnished to analyze their LCC. The paper addresses those 11 two gaps in the pavement economics body of knowledge by proposing a methodology for 12 using field test data to quantify the service lives of pavement preservation treatments for 13 both asphalt and concrete pavements. Additionally, it concludes that a LCC model based 14 on equivalent uniform annual cost, rather than net present value, specifically addresses 15 the relatively short term nature of pavement preservation treatments and allows the 16 engineer to better relate treatment LCC output to annual maintenance budgets.

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In the global aviation community, sustainability increasingly is becoming a priority for airport projects as a foundation for future prosperity. Pavement structures are an airport's greatest asset and greatest liability. Pavement management systems involve an intensive and expensive enterprise, and pavement maintenance projects consume massive amounts of nonrenewable resources at every airport in the nation. Little research has been conducted to assist airport pavement managers in reducing the environmental, economic, and social impacts of pavement maintenance and preservation processes. The old cliché of “what is not measured is not managed” applies, and a performance metric therefore is needed to permit pavement managers to measure sustainability. No standard, quantitative performance metric for sustainability is now in use by pavement managers assessing pavement treatment alternatives. This paper demonstrates how airport pavement managers can quantitatively analyze typical pavement treatments with a life-cycle cost analysis, quantification of raw material consumption, and the recently developed Greenroads standards to measure the environmental, economic, and social impact of the treatments for a given pavement project to enhance the overall sustainability of their programs.

Field pavement preservation research concerning two accepted methods for measuring pavement macrotexture was done on a state highway in Oklahoma. The 2.5-year project used the outflow meter ASTM STP 583 and the Transit New Zealand TNZ T/3 sand circle to measure macrotexture on 23 asphalt and concrete pavement preservation treatments. Through a protocol of monthly macrotexture measurements in the field, the researchers observed functional limitations, caused by the physical mechanics of the methods, on the accuracy of macrotexture measurements on both standard tests. It was found that the sand circle should be used on pavements with macrotexture greater than 0.79 mm (0.03 in.); the outflow meter should be used on pavements with textures of less than 1.26 mm (0.05 in.). Both tests were accurate in the range of 0.79 to 1.26 mm. These results applied to both asphalt and concrete pavements.