Thermal Analysis of Hot Mix Asphalt Pothole Repair by Finite-Element Method

Abstract

Traditional repair methods tend to suffer from inadequate net interface heating because the combined effect of placing hot fill mix in a cold, old pavement leads to inadequate net temperature levels. The outcome of this is low durability and limited life. In contrast, the outcome of placing hot mix in a controlled, preheated host pavement is substantial increased working life. To understand repair heating, this study ran heat transfer finite-element models for the cases of (1) hot mix asphalt (HMA) placed in an ambient temperature pothole, (2) the heated pothole recess, and (3) HMA placed in the preheated pothole recess. The air–pavement–heater system model comprises a host pavement with two pothole repairs or, in the case of the second thermal model, with one empty pothole excavation, and an infrared heating element plate. For calibration purposes, experimental work of simulated repairs undertaken in previous research was used. The air–pavement–heater system setup followed an optimum pothole preheating method also determined in previous research. Thermal models were validated with previous experimental work. It was concluded that the models generate reasonable transient temperature profiles within the dynamically heated pothole excavation, at the interface of the repairs, and inside the host pavement.