Assessment of mechanical performance of electrically conductive asphalt pavements using accelerated pavement testing

Electrically Conductive Asphalt (ECA) pavements are a promising technology for preventing snow and ice accumulation on roadways. This study assesses the mechanical performance of ECA pavements using Accelerated Pavement Testing (APT). Three pavement test strips were constructed in New Jersey: a traditional asphalt layer as test strip-I, an ECA mastic prepared using a combination of asphalt binder and conductive fibres (strip-II), and an ECA-HPTO (high performance thin overlay mixture) layer containing graphite and carbon fibres (strip-III). Each test strip was instrumented with asphalt strain gauges (ASGs), pressure cells, and thermocouples to evaluate the structural responses. A Heavy Vehicle Simulator (HVS) was used to apply 300,000 passes on each test strip using a 40-kN truck tire. The structural integrity of the test strips was evaluated by conducting Heavy Weight Deflectometer (HWD) testing before and after HVS loading. Data from the ASGs revealed that strip III exhibited the highest cracking resistance (nearly 2 times less tensile strain). The rut depths in all test strips were negligible (less than 2 mm). ECA mastic and steel electrodes in the ECA layer impact the structural integrity of test strips, with variations in HWD deflection behaviour indicating the role of electrode spacing in maintaining pavement stability.