Title: Interaction Model for Causes of Deterioration and Permeability of Concrete

Author(s): P. A. M. Basheer, A. E. Long, and F. R. Montgomery

Publication: Symposium Paper

Volume: 144

Issue:

Appears on pages(s): 213-232

Keywords: concrete durability; deterioration; diffusion; models; permeability; sorption; Materials Research

DOI: 10.14359/4399

Date: 3/1/1994

Abstract:
The deterioration of concrete may be due to corrosion of reinforcement, frost damage (including freezing and thawing), chloride ingress, concrete carbonation, sulfate attack, salt attack, alkali attack, acid attack, alkali-aggregate reaction, or abrasion. Investigation of concrete durability generally consists of either the causes of deterioration or its extent. Quite often, methods used to improve concrete durability aim at preventing deterioration; however, occasionally methods that can limit extent of damage are employed. In this context, and to propose tests that can assess the durability of existing structures, it is essential that a thorough analysis of the various relationships between material properties and deterioration mechanisms is carried out. It is believed that such an analysis would help focus the attention of investigators on the key issues that ultimately determine concrete durability. One of the fundamental properties influencing the initiation and extent of damage is permeation. A simple model for cracking-corrosion-permeability has been proposed. By following a similar approach, a detailed investigation of the causes of deterioration has been carried out and a model for each mechanism relating to the physical properties of concrete has been developed. Paper deals with these models and proposes a single model for all types of deterioration, emphasizing permeation properties. The need for targeting concrete durability in terms of permeation properties (sorptivity, diffusion, and permeability) is also illustrated.