InTrans / Mar 26, 2024
CP Tech Center reviews opening of concrete pavement to traffic
Strategies that enable new pavement surfaces to be opened to traffic earlier can shorten construction duration, improve safety by reducing the need for detours, and save costs for both agencies and contractors. (American Concrete Pavement Association, used with permission)
Several factors go into an agency’s decision on the ideal time to open a new concrete pavement surface to the traveling public. These can include everything from the work zone setup to the materials and construction methods used and from the expected traffic load to pavement strength development.
The National Concrete Pavement Technology Center (CP Tech Center) recently reviewed the science and strategies behind current practices for opening pavements to traffic to help agencies better understand the considerations associated with early opening of concrete pavement and potentially accelerate opening when needed.
“State-of-the-industry technical expertise and strategies that enable pavements to be opened to traffic at the optimum point may shorten construction duration, improve safety, reduce congestion, and save costs for both agencies and contractors,” reads the resultant technical summary published by the CP Tech Center, Optimizing Concrete Pavement Opening to Traffic.
It continues, “Additionally, if construction traffic can be allowed onto the pavement earlier rather than later, the reduction in the amount of time that traffic must be diverted or delayed can improve the sustainability benefits of a new pavement or overlay project.”
The research showed that current strength requirements—the most common assessment parameter—set by some transportation agencies may be overly conservative and could lead to mixtures that achieve strength quickly but may not be durable in the long term. Rather, it may be better to reduce opening strength requirements and use more durable mixtures. Alternatively, construction may be delayed while waiting for high strengths to be achieved.
Strength assessment using tools, including an online damage-based analysis tool, are discussed as alternatives to agencies’ current methods or standard strength requirements.
For early opening scenarios, the summary explores considerations such as “the type of expected traffic and its potential to contribute to fatigue damage, the strength development of the mixture and how it can be accelerated, the side effects of acceleration, and the costs and environmental impacts of acceleration.”
The summary also notes that the term “early” needs to be defined on a project-by-project basis in light of typical opening times.
In addition to covering the range of considerations involved in opening pavements to traffic, the technical summary discusses nondestructive testing applications for determining opening times and case studies from Iowa, Georgia, Ohio, California, Virginia, and Indiana that explore different construction scenarios.
The technical summary was published as part of the Federal Highway Administration (FHWA) cooperative agreement Advancing Concrete Pavement Technology Solutions. This summary and other publications produced as part of the ongoing cooperative agreement are available at the project page.
