Misconceptions or lack of understanding about concrete pavements often impact the selection of the best pavement type. Those who believe concrete pavements "cost too much," "take too long," or "are too difficult to repair" may be surprised to learn concrete costs less during the pavement's life cycle, can be opened faster than ever, and can be repaired easily with the proper equipment, materials, and processes.
Concrete pavements are well suited to withstand heavy traffic and harsh seasonal changes. Although many agencies realize these benefits, there are still highways across the country that require perpetual maintenance and repair or are unsafe. Each year, in fact, more than 13,000 people die on the nation's highways because of poor road conditions, according to the U.S. Department of Transportation's National Highway Traffic Safety Administration.
A recent comparison of initial costs of pavements across the nation indicates the difference in initial costs between concrete and asphalt pavements of similar structural capacity may be as little as 8 percent.
Determining true pavement costs should include indirect costs associated with work zones and maintenance. Quality concrete pavements require little to no maintenance, a clear advantage over flexible pavements, which require frequent roadway maintenance and rehabilitation, resulting in traffic congestion, high user costs, and work zone safety issues.
The time required to construct concrete pavements is generally equal to or less than a multi-lift asphalt pavement. Concrete pavements are constructed in a single lift and may be paved full width or in single-lane width, depending on specific project requirements.
The use of fast track paving techniques and materials significantly reduces construction-related traffic delays. High performance concrete mixes may exceed 400 psi flexural strength in four hours, allowing overnight or weekend construction projects to open quickly.
In addition, concrete maturity meters and corresponding strength correlations are now used routinely by a number of agencies in determining realistic strength-based opening times.
Concrete pavement restoration can return a pavement to a near-new condition. For example, dowel bar retrofit can enhance structural capacity, and then can be followed by diamond grinding to restore ride quality, a functional issue.
By Mike Ayers, Ph.D.
Director - Highways & Concrete Pavement Technology, American Concrete Pavement Association, Skokie, Ill.
