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MATERIALS ENGINEERING 

MATERIALS ENGINEERING

A pavement’s life expectancy is directly related to the quality of surfacing used.

Hot Mix Asphalt

There is a deep science behind the design and construction of asphalt. Choices regarding binder grade, rock size, design compaction targets, RAP content and thickness all help define how the asphalt will perform in a pavement. Incorrect choices can lead to unexpected high costs, either in construction efforts or in long-term maintenance efforts.

The answers to these questions are very different depending on application. A mix designed to perform well structurally on an interstate may likely experience environmental cracking in a cul-de-sac. A mix designed to be durable on low volume roads may end up rutting if placed on a high-volume arterial.

Also part of the asphalt equation are the pavement design and construction. The thickness of the pavement should be based on the asphalt mix’s expected performance. Since not all asphalts perform the same, pavement designs should include asphalt mix design parameters that were used in the design. A well-designed mix can still fail if not placed at proper thickness or properly constructed in the field.

PEPG specialize in the design, evaluation and construction management of pavements and all their component materials. We can help you make the right decisions regarding what pavement and mix designs to use based on your available resources and the pavement applications.

Portland Cement Concrete

There is more to Portland cement concrete (PCC) than strength. PCC mix design and performance in a pavement is related to paste content and composition, water content, aggregate quality and gradation. Just as important, if not more so, is the construction and curing practices used. Failure to properly consolidate, cure or  seal a concrete surface can result in decreased performance. As with Hot Mix Asphalt, incorrect choices can lead to unexpected high costs, either in construction efforts or in long-term maintenance efforts.

In addition to the mix design, proper thickness design of the concrete surface will have short and long-term cost impacts. Typical practices are conservative and can result in excessive thickness designs where they are not needed. Failure to properly categorize the base strength can result in surfaces that are too thin and can crack. Optimum design of a concrete pavement requires a deep knowledge of the performance characteristics of the materials being used and the proper practices to construct them.