Development of a Pressurized Blister Test for Interface Characterization of Aggregate Highly Polymerized Bituminous Materials

Abstract

Bituminous crack sealants are commonly used for pavement maintenance. While cracks in pavement are inevitable, sealing the cracks helps maintain the integrity of the pavement by preventing water and debris from entering the structure. Sealing cracks increases pavement service life up to 5 years, and this can lead to significant cost savings for the U.S. highway system. Crack sealing is a cost-effective maintenance approach, provided that the right sealant is selected and properly installed. However, sealant selection is difficult because of the lack of a rheology-based standard test that correlates with field performance. To address this drawback, performance-based guidelines for the selection of hot-poured crack sealants have been developed by a research team, including the writers. To complement these guidelines, this paper describes a recently developed adhesion test procedure that predicts interface bonding based on a fundamental property of the interface, interfacial fracture energy (IFE). This recently developed pressurized blister test is a fracture test. The principle of the test is to break the interface bonding by pressurizing the interface between the adhesive and adherend. The amount of pressure and the deformation of the adhesive before and during the debonding period are used to calculate the IFE. The test variation is acceptable because its average coefficient of variation is 8.7%. This paper describes the test apparatus and procedure and discusses the adhesion of several hot-poured bituminous sealants to aluminum, limestone, quartzite, and granite.