Engineering Performance, Environmental and Economic Assessment of Pavement Reconstruction Using Cold In-Place...

Modernizing municipal roads requires rehabilitation strategies that ensure adequate structural performance while reducing environmental and economic burdens. Although cold in-place recycling with foamed bitumen (CIR-FB) has been widely investigated, integrated assessments combining mechanistic-empirical modeling with LCA and LCCA remain limited-particularly for municipal roads in Central and Eastern Europe, where reclaimed asphalt pavement (RAP) quality, climatic conditions and budget constraints differ from commonly studied regions. This study compares two reconstruction variants for a 1 km road section: a conventional design using virgin materials (V₁-N) and a recycling-based alternative (V2-Rc) incorporating RAP from the existing wearing and binder layers and reclaimed aggregate (RA) from the existing base. CIR-FB mixture testing (stiffness ≈ 5.25 GPa; foamed bitumen = 2.5%, cement = 2.0%) was integrated into mechanistic-empirical fatigue analysis, material-flow quantification, LCA and LCCA. The V₂-Rc variant achieved a 3-21-fold increase in fatigue life compared to V₁-N at equal thickness. Material demand decreased by approximately 27%, demolition waste by approximately 39%, and approximately 92% of the existing pavement was reused in situ. Transport work was reduced five-fold (veh-km) and more than six-fold (t-km). LCA showed a 15.9% reduction in CO₂-eq emissions, while LCCA indicated approximately 19% lower construction cost, with advantages remaining robust under ±20% sensitivity. The results demonstrate that CIR-FB, when supported by proper RAP/RA characterization, can substantially improve structural, environmental and economic performance in municipal road rehabilitation.