National Concrete Pavement Technology Center

Project description

Available guidance for concrete joint sawing provides some information on best practices, but falls short on the more unique and more recent issues involved with the process. One such issue is related to the different types of coarse aggregates that are found to be included in Iowa’s concrete paving mixtures. The varying types of aggregates can have very different mechanical responses to the process of saw cutting, including the types of saw blades. To present, contractors and agencies have had to rely on past experience and experimentation to select proper methods and materials. Adequate guidance on saw cutting will help prevent issues such as raveling, spalling, early age cracking and some forms of joint deterioration. Joint sawing practices today also have the additional element of recent Occupational Safety and Health Administration (OSHA) requirements regarding silica dust, which is a byproduct of dry sawing processes (including early entry sawing). The silica dust issue has prompted some contractors to consider a return to wet sawing practices, but this may carry with it the issue of slurry collection and disposal. Agency engineers and contractors are engaged in a search for the best methods and equipment to efficiently meet the new OSHA requirements and to protect their workers’ health. The goal of this project is to develop a best practices guide for concrete pavement joint sawing in Iowa.