Assessment on Bonding Potentials of Trackless Tack under a Thin Overlay

Abstract

Trackless tacks are used to minimize the loss of tack materials caused by adherence to moving tires. During the last two decades, the paving industry and highway agencies have had an increasing interest in the use of trackless tacks to ensure an adequate bond between the overlay and the existing pavement. Therefore, the need for more studies on the bonding characteristics of various trackless tacks is growing. The purpose of this study is to measure the bonding potential of trackless tacks and identify several variables that affect the shear resistance in terms of bonding strength and energy using statistical analysis. The improvement of interlayer shear resistance by tack treatment is different depending on the tack and surface types. Higher tack reactivation temperatures increase the interlayer shear resistance. Compaction effort is considered to have only a marginal effect on bond performance. Tack and surface types play a more critical role in determining the shear bond strength than residual tack rate in the field experiment.

Evaluation of the Polymer Modified Tack Coat on Aged Concrete Pavement: An Experimental Study on Adhesion Properties

“…To provide a broader perspective, a comparison of the results obtained in this study with those reported by other authors supports the effectiveness of the newly developed trackless tack coat in improving adhesion strength, tensile bond strength, and shear behavior. These results are consistent with prior research by various authors, including Dian et al (2018) [38], Seo et al (2021) [27], and Peng et al (2023) [25]. By considering the collective evidence, it becomes evident that the trackless tack coating method offers superior performance compared to conventional tack coating methods.…”

“…One approach is to use simultaneous installation equipment, such as the Spray Paver shown in Figure 2, which attaches a tack coat spraying device to the asphalt paver and spreads the asphalt mixture while spraying the tack coat. The simultaneous laying method prevents tack coat loss caused by transport trucks and pavers by spraying the tack coat from the lower part of the paver to the back of the paver track and in front of the screed [27,28,33]. Although this method can prevent tack coat loss, it cannot secure tack coat curing time during the construction process.…”

“…One of the key advantages of trackless tack is its quick break time, typically ranging from 5 to 15 min. This means that the tack coat material undergoes a rapid transformation, transitioning from a wet state to a tacky state and eventually setting [27]. This quick break time allows for efficient application and reduces the chances of the material being inadvertently picked up by passing equipment.…”