Paper by SUKSAWANG OZKUL from ISCR 9th 2004 Instanbul Turkey
The use of high performance concrete (HPC) is becoming more popular in the United States. Many State Departments of Transportation are replacing conventional concrete especially with HPC bridge decks. Despite the growing popularity of the material, little is known on the effect of the available curing methods on the mechanical properties and durability of HPC. This paper presents results that are part of an overall study for the New Jersey Department of Transportation (NJDOT) to develop and implement mix designs and technical specifications for HPC transportation structures such as bridges and concrete pavement roadways. The paper determines the best curing practices by comparing different curing methods such as moist curing, air-dry curing, wet burlap curing, and curing compound. The effect of curing methods on compressive strength, rapid chloride permeability, and early-age as well as drying shrinkage were investigated. Results show that the curing duration had an effect on both mechanical and durability performance of HPC. Moreover, moist curing (burlap) should be applied immediately or at least within 3 hours after pouring to avoid early-age shrinkage.