Assessing pavement sustainability requires jointly evaluating structural performance and environmental impacts, yet these dimensions are often analyzed separately. This study proposes an integrated framework combining mechanistic–empirical pavement design and life cycle assessment (LCA) to quantify the structural–environmental trade‐off associated with asphalt‐emulsion stabilization of subbase soils. Structural performance was assessed in MeDiNa using fatigue cracking and rutting criteria, while a cradle‐to‐construction LCA was conducted in SimaPro based on ISO 14040/14044, using Ecoinvent and SICRO (2023) data. Four subbase scenarios were compared: natural soil at optimum moisture and the same soil stabilized with 1%, 2%, and 3% asphalt emulsion. Stabilization substantially increased subbase stiffness and allowed a reduction in asphalt surface thickness. However, although all scenarios satisfied the structural criteria over the 10‐year design period, the thinner asphalt layer increased wheel‐path rutting, while fatigue remained the governing design criterion. From the environmental perspective, higher emulsion contents led to progressively higher CO 2 ‐equivalent emissions and water consumption, with emulsion production and transport emerging as the dominant hotspot. The results show that structural optimization does not necessarily translate into lower environmental impacts. Therefore, no single optimum solution was identified, and pavement design should adopt a multi‐criteria perspective to explicitly balance structural gains against environmental burdens.
Medeiros et al. (Thu,) studied this question.