A Test Method to Evaluate the Adhesive Property between Asphalt and Aggregate Based on Simulating Actual Working Conditions

Jianhua Liu,Mutian Sun,Zhenyang Fan,Wenyuan Huang,Shaoming Wu,Xiaobo Du

doi:10.3390/su14042160

Abstract

The adhesive property between asphalt and aggregate is a crucial factor that affects the resistance of asphalt pavement to moisture damage. In this study, by simulating the actual working conditions of asphalt–aggregate bonding characteristics, test equipment was developed and a method for evaluating the adhesive properties between asphalt and aggregate—the brush damage test—was proposed. A steel-wire brush as the brush type, a total of 0.5 kg/m2 asphalt content, 70 °C as the maintenance temperature, and 4 h as the maintenance time, as well as mass loss rate (ML) of specimens before and after brushing, were used as the evaluation index. The brush damage test was conducted on five commonly used asphalt binders and two commonly used aggregates. Finally, the results of the brush damage test were analyzed in comparison with those of a binder bond strength (BBS) test. It was indicated that the evaluation results for the adhesive properties between asphalt and aggregate were not consistent under the two test methods. The pull-off tensile strength under dry conditions (POTSdry) and under wet conditions (POTSwet) when ignoring the influence of the texture of aggregate did not reflect the adhesive properties. ΔPOTS, representing the ability of asphalt to resist the loss of adhesion strength due to moisture damage, can be used to evaluate the adhesion properties between asphalt and aggregate. Under appropriate conditions, the brush damage test has the advantages of simple operation, high credibility, and good discrimination.

Highlights

As a basic pavement material, the most important role of asphalt is to bond aggregates to form a solid surface for transportation
The adhesion property between asphalt and aggregate is the basic prerequisite for durability and other performance parameters of asphalt pavement [1]
Mogawer et al [29] studied the moisture stability of a warm-mix asphalt mixture using a Hamburg wheel-track device (HWTD) and the binder bond strength (BBS) test; the results showed that there was no correlation between the HWTD test and the BBS test

Summary

Introduction

As a basic pavement material, the most important role of asphalt is to bond aggregates to form a solid surface for transportation. The adhesion property between asphalt and aggregate is the basic prerequisite for durability and other performance parameters of asphalt pavement [1]. A number of studies [2,3,4,5] have shown that such damage is closely related to the adhesion property between asphalt and aggregate. For research on the adhesion property between asphalt and aggregate, there are many evaluation methods and indexes. A unified and extensive evaluation system has not yet been formed. The evaluation methods include peeling evaluation, surface energy evaluation, and mechanical testing

Methods

Results

Conclusion