Title:
Effect of Alkali Silica Reaction Expansion and Cracking on Structural Behavior of Reinforced Concrete Beams
Author(s):
Shenfu Fan and John M. Hanson
Publication:
Structural Journal
Volume:
95
Issue:
5
Appears on pages(s):
498-505
Keywords:
alkali-silica reaction (ASR); compressive strength; cracking;
dynamic modulus; expansion; flexural loading capacity; reinforced concrete beams;
splitting tensile strength;
DOI:
10.14359/564
Date:
9/1/1998
Abstract:
A laboratory study was carried out to investigate the effect of deleterious ASR expansion on the structural behavior of reinforced concrete beams and on mechanical properties of cylinders made with the same concrete. The specimens were conditioned by immersion in a cyclically-heated alkali solution for one year to accelerate ASR. To simulate in-service conditions, two beams were held under load that caused flexural cracking while being conditioned. Cracks were first observed in the cylinders at an age of 125 days. Before ASR cracking occurred, changes in the mechanical properties of the reactive cylinders were minor. After cracking, the compressive strength, splitting tensile strength, and dynamic modulus of the cylinders were significantly reduced. Cracks were first observed on top of the beams after 6 months of conditioning and were oriented in the direction parallel to the reinforcement. However, after conditioning for one year, the flexural strength of the reactive beams which experienced ASR cracking was nearly the same as that of the nonreactive concrete beams. Effect of ASR on flexural strength of the pre-loaded and cracked beams was also insignificant.