Development of advanced temperature distribution model in hot-mix asphalt patch repair

Abstract

The performance of hot-mix asphalt patch repair is greatly reduced due to inferior compaction at the interface. It is known that the faster loss of temperature at the interface is one of the primary reasons for inferior compaction. A novel controlled pothole repair system (CPRS) has been developed as part of this study. The CPRS uses infrared heating technology with enhanced features compared to many existing infrared systems. In parallel, a three-dimensional finite-element thermal model capable of modelling the loss of temperature during the patch repair process has been developed. The first part of the paper presents the functionality of CPRS, including experimental results to demonstrate various features of the system. In the second part, the numerical results are compared against experimentally measured values from a patch repair in a controlled laboratory condition. The tests are done to measure the influence of no preheating and preheating of the existing surface on the temperature loss. The results showed more than 80% agreement between simulation and actual measurements. It is also shown that preheating of the existing surface can significantly reduce temperature loss at the interface, thus allowing more time for repair and the possibility of achieving better compaction.

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

“…The pothole repair models and the heated excavation model were a representation of experimental work conducted by the authors. All models were validated and calibrated by the authors' experimental work (Byzyka et al 2017a(Byzyka et al , 2018a and form a platform for the future development of an integrated repair guideline beginning with the excavation of pavement distress and culminating in its repair with infrared heat (Fig. 1).…”

“…These simulations were developed using ANSYS software (ANSYS Workbench 2019). A preliminary version of the dynamically heated pothole excavation is published in Byzyka et al (2017a) but has since undergone significant alterations and improvements. These improvements were applied to all models.…”

“…Three geometries were designed for the simulations: a host asphalt pavement, a pothole fill, and a heating element plate of an experimental infrared heater presented in Byzyka et al (2017a). The simulated asphalt mixtures were dense graded mixtures with 20-mm maximum aggregate size [commonly known as 20-mm dense bitumen macadam (DBM)] for the host pavement and 6-mm maximum aggregate size [commonly known as asphalt concrete (AC) 6] for the repairs.…”

“…The ambient temperature ranged between 18°C and 22°C. A preliminary version of this experimental method was published in Byzyka et al (2017a) but has since undergone refinements to capture the precise distribution of plate temperatures. These alterations are the number of temperature sampling points, the temperature probe used for the measurements, and the time duration of the measurements.…”

An improved interface temperature distribution in shallow hot mix asphalt patch repair using dynamic heating

“…Whereas dynamic repair is a repair during which the empty pothole excavation has been pre-heated with an experimental infrared heater prior to filling and compaction. The heater is presented in Byzyka et al (2017a). Its main features include two plates that are capable of heating asphalt independently by radiating heat at different heat powers; an advanced controller; and controlled infrared heat application with heater being at different offsets from the pavement, in motion or stationary above the repair.…”