Book Description

During roadway repairs, state highway officials try to minimize lane closure times. This reduces inconvenience to travelers, reduces traffic control needs, and helps minimize work zone accidents. For rapid repairs, materials that provide high early strength are needed. Pyrament blended cement (PBC) is marketed to produce concretes having a high early strength and long-term durability in varying climatic conditions. Concretes containing PBC were placed in full-depth patches in August 1989 and March 1990 under different temperature conditions. Type III cement concretes were used as controls in patches placed during August only, since specifications did not permit their use when the ambient temperature was below 13°C (55°F). Tests of the concretes and the field performance of the patches indicated that PBC concrete has high early and 28-day strengths, even in cold weather, and that the temperature and strength development is faster than in the control concretes. PBC concretes have the low permeability needed for durability and provide satisfactory resistance to freezing and thawing without the addition of an admixture during mixing.