Sustainability and Performance Assessment of Pavement Preservation Strategies in the Southwest Region
📨 Principle Investigator: Hasan Ozer
🤝 Sponsor: Southwest Pavement Technology Consortium (SWPT)
📅 Timeline: 2025 – Ongoing
Highlights
Introduction
Pavement preservation is the proactive side of road maintenance: instead of waiting for a road to deteriorate until it needs expensive reconstruction, preservation programs apply targeted treatments at the right time to slow that deterioration and extend the pavement’s useful life. Done well, preservation costs a fraction of reconstruction while achieving most of the same service-life benefit. The challenge is choosing the right treatment at the right time for the right pavement. A decision that depends on pavement condition, traffic volume, climate, budget constraints, and increasingly, environmental impact. In Arizona, where an extensive local agency road network faces both extreme heat and tight municipal budgets, the stakes of that decision are high.
Methodology and Framework
The research is organized into four sequential phases. Phase I establishes the sustainability baseline through a literature synthesis and case study analysis: three recent Arizona preservation projects will be selected with panel input, and a multi-attribute sustainability evaluation — covering cost, environmental impact, and pavement performance — will be conducted for each. Life Cycle Assessment will follow the FHWA pavement LCA framework, using open-source inventory databases and tools like FHWA’s LCAPave to quantify greenhouse gas emissions and environmental trade-offs relative to conventional mill-and-overlay alternatives. Life Cycle Cost Analysis will complement the LCA to capture the full economic picture across all life-cycle stages.
Phase II moves from case studies to generalized models: a structured agency survey and data collection effort will gather historical preservation data from Arizona local agencies, including treatment decision rules, before-and-after condition records, and construction specifications for projects from the last 5-10 years. This database will power treatment lifetime and pavement life extension models using two established approaches: one based on pretreatment condition levels, and one based on specified condition thresholds. Where historical data is insufficient, the analytic network process (ANP) will integrate expert opinion into model development. Phase III translates these models into accessible guidance and Phase IV lays out a field-testing plan to validate the most promising treatments across a range of roadway classes.
Expected Outcomes
Treatment Performance Models and Cost-Effectiveness Analysis
A core deliverable of Phase II is a set of calibrated service life and performance models for preservation treatments commonly used across Arizona. These models will be built on real condition data from local agencies, distinguishing between treatment families and accounting for differences in surface type, traffic, and climate subregion within Arizona. The models will quantify both the expected life extension from each treatment and the pavement condition trajectory before and after treatment application. From these models, a cost-effectiveness analysis will determine which treatments provide the greatest return on investment for different pavement types and condition states, combining traditional LCCA metrics with the environmental sustainability results from Phase I.
The service life prediction approach will adapt two well-established methods from the literature: Approach A (measuring life extension relative to pretreatment condition level) and Approach B (measuring life extension to a defined condition threshold). By comparing both approaches against Arizona field data, the research will establish which method is more reliable for the range of treatments and agency contexts encountered in the region. Where data is sparse, particularly for newer or less commonly used treatments — expert elicitation through the ANP framework will supplement field data to ensure that the models are actionable even in data-limited situations.
Sustainability Integration and Decision Support
Phase III will synthesize the performance models, sustainability assessments, and cost-effectiveness findings into a practical decision support tool. One-page treatment brochures will be prepared for each preservation treatment commonly used in the SWPT region. Designed for a wide audience, the brochures will summarize each treatment’s appropriate application conditions, expected performance, cost range, and sustainability profile in a format that supports training and knowledge sharing. Together, the dashboard and brochures represent a practical technology transfer mechanism that ensures research findings reach the practitioners who most need them.