Performance of Concrete Pavement Mixtures with Marginal Aggregates: Laboratory Investigation

Pavement engineers strive to design and construct portland cement concrete (PCC) airfields that are high quality and economical to maintain during their intended lifecycle. When designing concrete mixtures, locally available materials are desired to minimize transportation or processing expenses. Aggregate costs are of significant concern, because aggregate comprises 70% of the mixture volume. To reduce cost, local aggregates of marginal quality may be used in production; however, the use of these materials may reduce concrete quality and pavement performance. A laboratory investigation of 16 different aggregate materials was conducted, where each aggregate’s physical properties were in some way outside of the U.S. military’s specifications. Recycled materials were also included in the analysis because these materials are generally perceived as inferior. Forty-three mixture designs were created, where one mixture component or material property varied from a specified control mixture. Different proportions of each material were considered to test the effect of deviating from current specifications. Compression and flexural strength test specimens were cast for testing at 28 and 90 days, utilizing 850 total specimens. Statistical analyses were used to evaluate the effect of marginal quality aggregates on concrete strength.