Modeling pavement surface deflections under accelerated pavement testing using the PCA method

When subjected to traffic loading, one response mechanism of a pavement structure is to endure surface deflections. These surface deflections are a quantitative function of the pavement's integrity and are often used for pavement structural condition and performance evaluation. In this paper, the principal component analysis (PCA) method was utilized to model the pavement surface deflections as a function of wheel load, wheel speed, number of load cycles, and temperature under accelerated pavement testing (APT) using the MLS30 device. The APT test site comprised typical flexible pavement structures with an asphalt surfacing layer, a base, and a subbase resting on the subgrade. The scope of work included indoor APT trafficking with the MLS30, surface deflection measurements, PCA model formulation, and data analysis. Among the surface deflection basin parameters evaluated, the maximum deflection and area factor exhibited the best correlation with temperature, registering a coefficient of correlation exceeding 90%. Overall, the study contributes to the literature enrichment through substantiation of the PCA as a potential analytical method for simulating and modeling the pavement surface deflections under moving wheel loads and fluctuating temperature conditions.