Improvements to the Construction Process for Semi-Rigid Pavement Rehabilitation on Mexican Highways

The Mexican Federal Government has allocated a great deal of investment to the maintenance of pavements across the existing road network (in 2010 and 2011, this investment amounted to €7,860M and €7,894M respectively). During the 1990s, a pavement system was introduced in Mexico involving the incorporation of Portland cement using a mechanical process (grader) in order to improve the mechanical properties of the lower layers (base and subbase), thereby increasing their strength. However, homogenization of the stabilized base has never been achieved using this construction process. Currently, a process is being employed that involves reclaiming part of the existing pavement and incorporating Portland cement directly in situ using automated equipment, thereby allowing homogeneous application at the lower layers. The aim of this research is to examine the impact on the performance of the lower layers of semi-rigid pavements as a result of using automated equipment on Mexico’s major highways. In order to achieve this goal, comprehensive monitoring and data analysis was performed, based on the falling weight deflectometer (FWD) as a key tool for in situ evaluation (mainly in terms of base deflection and moduli).