Book Description

This study evaluated the properties of three high performance concrete mixtures placed in a jointed plain concrete paving project on I-64 in Newport News, Virginia, to reduce the shrinkage and improve the flexural strength of the concrete. Two mixtures contained ground-granulated blast furnace slag with 2-inch and 1-inch nominal maximum size (NMS) aggregate, and the third mixture contained Class F fly ash with 1-inch NMS aggregate. Air-entrained paving concretes with satisfactory strength, low permeability, and dimensional stability were prepared using concretes with Class F fly ash or slag and 1-inch or 2-inch NMS aggregates. Slipform pavers satisfactorily placed these concretes. The test sections were in excellent condition after six winters based on a visual survey. Falling weight deflectometer data indicated a better load transfer with the larger aggregate size with everything else being equal. The study also evaluated the maturity method in the continuation of the project on I-64 in Hampton, Virginia. After the evaluation, the pavement was changed to continuously reinforced concrete and the concrete properties were tested in accordance with the recently introduced Guide for Mechanistic-Empirical Design of New and Rehabilitated Pavement Structures (known as the proposed AASHTO M-E Design Guide). In the Hampton portion, a Class F fly ash mixture with the 1-inch NMS aggregate was used. The use of large aggregate, provided the particle shape is acceptable, and uniform combined grading should be specified for concretes with reduced water and cement contents. The maturity method can be used to determine the pavement's readiness for opening to traffic and should be included in the specifications.