Elastic Moduli of Cement-Bitumen Treated Materials and Existing Pavement Structure During Early Curing: A Case Study

Pavement structures incorporating Cement–Bitumen Treated Materials (CBTM) provide a sustainable approach for rehabilitating distressed pavements. However, the field-scale spatial variability of CBTM and its early-age stiffness evolution remain poorly understood, limiting predictions for traffic reopening and overlay placement. This paper investigated early-age stiffness development and spatial variability of CBTM, along with its interaction with the existing pavement, in a rehabilitation in Blainville, Canada. Deflections were recorded across nine subareas at 0, 24, and 48 h, and elastic moduli were backcalculated and temperature-corrected. Non-parametric analyses assessed differences among CBTM groups, complemented by descriptive statistics for the existing pavement. CBTM exhibited rapid stiffness gain, with longitudinal variability exceeding transversal variability. Integrating in-situ deflection monitoring, temperature-corrected backcalculation, and continuous defect tracking offers a robust framework for predicting early-age CBTM performance and supporting sustainable, informed pavement rehabilitation decisions.