High Performance Concrete and Reinforcing Steel With a 100-Year Service Life

摘要

>This paper reviews chloride permeability issues for conventional and high performance concretes so as to provide realistic design and specification guidance for the construction of concrete structures in harsh environments. This review briefly discusses cracking issues of high strength, high performance concretes, a significant detrimental issue created by restraint to thermal and shrinkage contractions during the first 60 days of a structure’s life and by the high modulus of elasticity and the low creep factors inherent with high performance concretes. The last portion of the paper reviews the five-year (1993 to 1998) Federal Highway Administration (FHWA) study at Wiss, Janney, Elstner Associates, Inc. (WJE) on high performance, corrosion resistant steel reinforcing bars. This FHWA study was successful in identifying bar types that can provide 75 to 125 years of design life, even in the presence of cracks in the concrete when exposed in harsh saltwater environments.