Crack Sealing Cost Effectiveness Project

The objective of this research study is to determine the most economical and effective materials and methods for sealing cracks in flexible pavements in the state of Montana. This investigation involves the placement of experimental test sections as part of larger crack sealing projects, followed by visual monitoring. Several sealant materials and several sealing techniques have been included in this investigation.

Sealing cracked asphalt pavements to prevent the intrusion of water into the pavement structure has long been a standard practice of the Montana Department of Transportation (MDT). Therefore, MDT has sponsored an extensive research project investigating eleven sealant materials and six crack sealing techniques at four locations about the state. Installation of the test sites was accomplished over three construction seasons. A control section, which was neither sealed nor routed, was included at two of the test locations. The goal of this research is to determine the most economical and effective method of sealing pavement cracks for this state. Monitoring of the test locations is scheduled for five years to end in 2002 following the guidelines of the Strategic Highway Research Project (SHRP) H-106 project. Interim reports are provided to MDT annually. Failures are categorized according to material failures (primarily adhesion and cohesion failures), and construction failures (primarily secondary cracking) according to Strategic Highway Research Project (SHRP) criteria. A qualitative rating is issued via SHRP guidance.