Laboratory and Field Investigation of the Effects of Biosealant Applications to the Surface of Asphalt Pavement

Abstract

Pavement preservation plays a significant role in maintaining aging pavement infrastructure under severe budget constraints. An important component in this is the application of sealants to surface asphalt pavements. A recent study investigated the field performance and mechanical properties of asphalt mixtures from pavement sections treated with four sealants, including two new products called biosealants. Field cores from both the control and the treated section were collected, from the tops of which thin beam specimens were cut to perform creep and strength tests at low temperature. The core bottoms were used to prepare laboratory-treated samples using an application process that mimics the spraying of sealant in actual field conditions. These samples were also tested at low temperature. Based on the creep stiffness and strength results, no significant effects were observed for the field-treated mixtures but a number of significant effects were observed for the laboratory-treated mixtures. The results of Fourier transform infrared spectroscopy (FTIR) analysis supported the laboratory findings. As part of field performance testing and monitoring, distress surveys of the shoulder test sections were performed after sealant application, and laboratory findings were also verified using cracking values of the treated and untreated field sections.