Title: Ordinary and Long-Term Durability of Reinforced Concrete Structures

Author(s): M. Collepardi

Publication: Symposium Paper

Volume: 192

Issue:

Appears on pages(s): 1-18

Keywords: cathodic protection; corrosion; durability; epoxy resins; reinforcement; steels

DOI: 10.14359/5738

Date: 4/1/2000

Abstract:
Durability of reinforced concrete structures (RCS) seems to be poor when compared with those of ancient un-reinforced structures. When ordinary durability (service life of 40-50 years) is needed, the poor behavior of RCS stems from human negligence in adopting the well consolidated and available experiential knowledge. However, for long-term durability requirements (service life of 100 years and more) the inherent vulnerability of the steel-concrete system must be taken into account. The inherent vulnerability of RCS substantially depend on the following "weak points" of concrete: (I) Low tensile strength (ii) High modulus of elasticity (iii) Microcracking caused by restrained thermal and drying shrinkage or service loading. This paper critically examines some possible future scenarios to achieve long-term-durability in RCS, including: a) Improvement in the corrosion behavior of the metallic reinforcement through the use of corrosion inhibitors, protection of the reinforcement with a coating, chance in the composition of reinforcing bars, or cathodic protection. b) Use of non metallic reinforcement. c) Increase in the tensile strength and/or ductility of concrete mixtures based on rubber-like polymer additions. d) Surface coatings for concrete protection.