Full-depth reclamation with hydraulic and bituminous binders, also known as cement-bitumen treated materials (CBTMs), is a cost-effective and eco-friendly road rehabilitation method that fully reutilizes preexisting local materials. The mechanical behavior of stabilized materials changes over time due to curing, which is crucial for long-term performance, so adapted on-site quality control (QC) strategies are necessary. This article proposes a methodology for using lightweight deflectometer (LWD) experimental data to assess CBTM properties at different locations and curing times using backcalculation. Multiple data processing techniques and four backcalculation methods for modulus values are introduced: (1) the surface modulus obtained by Love’s solution using only one deflection (ES1Love); (2) the surface modulus obtained by Love’s solution using three deflections (ES3Love); (3) the surface modulus obtained by a finite element–based backcalculation approach using three deflections (ES3FEM), considering the pavement as composed as one single semi-infinite layer; and (4) the elastic modulus of the two distinct materials or layers (CBTM and subgrade), backcalculated with the finite element method and using three deflections (ECBTM3FEM and ESG3FEM). Comparisons between surface modulus (ES) and the moduli set (ECBTM and ESG) demonstrate the fourth method effectively assesses each material’s contribution to pavement stiffness, which is important in evaluating the CBTM layer. The research concludes that LWD is an efficient QC tool for CBTM and that using backcalculated elastic moduli for the separated layers provides better results than the surface modulus for monitoring material evolution over curing time, and this may be important in the case of CBTMs.

The RILEM technical committee on Performance-based Asphalt Recycling TC 308-PAR is dedicated to advancing research, promoting knowledge exchange, and disseminating information related to asphalt material recycling. Within this framework, Task Group 1 (TG1) “Performance-based Evaluation of Cold Recycled Asphalt Mixtures” concentrates on aligning laboratory testing methods with the real-world performance of cold recycled asphalt mixtures. To this end, TG1 members collaborated to share the various cold recycling practices adopted in their respective countries. This collaboration aimed to compare specific procedures, technical specifications, and expected performance outcomes. The participants diverse backgrounds, spanning differences in road classifications, traffic loads, climatic conditions, and availability of materials, enabled the development of a comprehensive overview of current methodologies and provided insights into the potential expansion of cold recycling applications. The comparative study of national practices has been structured into two papers: Part I focuses on the constituent materials and mixture composition, while Part II addresses testing protocols and the construction process. In detail, Part II reports a critical comparison of testing procedures, mechanical characteristics, construction methods and quality control procedures used in Italy, Canada, Poland, Brazil and USA, either adopted by selected road administrations or established by reference standards. Accordingly, all initial assumptions, terminology, definitions, and the general context presented in Part I should be considered fully referenced and applicable. This paper focuses on recycling techniques using both cement and bitumen as binders. Conversely, although the use of cement alone is a recognized and widely applied technique, as reported in Part I, Part II does not consider it, since a greater degree of uniformity in procedures and knowledge has already been achieved and shared worldwide.

The full-depth reclamation with no stabilization (FDR-NS) is widely used as a pavement rehabilitation technique. It is important to evaluate the on-site characteristics of FDR-NS materials to avoid short-term underperformance. The need for performance-based testing could then be supported by in situ and non-destructive testing, such as dynamic cone penetrometer (DCP). DCP allows to estimate the bearing capacity of the pavement structure and to verify its homogeneity according to the depth. The objective of this research is to evaluate the applicability of using DCP to assess the quality of FDR-NS. Overall, DCP results showed a good reliability, allows to measure the effective depth of reclamation and to observe a significant reduction (average of 75%), in terms of DCP values, between before and after the reclamation (FDR) process. Thus, the potential of using DCP for FDR-NS rehabilitation was confirmed. The results from this research provide a rational basis for establishing specifications.

Quebec Ministry of transportation currently limits the use of reclaimed asphalt pavement (RAP) materials to 10% in surface courses, due to the potential risks associated with cold weather. This restriction hinders the adoption of high RAP content mixes (>10%), which are nevertheless beneficial for reducing the carbon footprints of the asphalt materials sector and designing more environmentally and sustainable pavements. A study was therefore carried out to optimize the formulation and performance of high-RAP asphalt mixes in cold climates. The study evaluates the linear viscoelastic (LVE) behaviour using the complex modulus test and low-temperature performance (thermal stress restrained specimen test (TSRST)) of an Enrobé Semi-Grenu 10 mm (ESG10) mix with RAP contents ranging from 0% to 100%, using a PG 52S-34 binder. Complex modulus tests were fitted to the 2S2P1D model. TSRST tests measured cold performance. The results show that above 20%, stiffness increases and modifies the E2/ E1 (viscous modulus ( E2) and elastic modulus ( E1)) ratio. Up to 30%, the addition of RAP does not significantly affect thermal performance or LVE behaviour.