Title: Effect of Multiaxial Stresses on Alkali-Silica Reaction Damage of Concrete

Author(s): Bishnu Prasad Gautam, Daman K. Panesar, Shamim A. Sheikh, and Frank J. Vecchio

Publication: Materials Journal

Volume: 114

Issue: 4

Appears on pages(s): 595-604

Keywords: alkali-silica reaction; damage rating index; expansion; mechanical properties; multiaxial stresses

DOI: 10.14359/51689617

Date: 7/1/2017

Abstract:
Alkali-silica reaction (ASR) causes expansion, cracking, and degradation of the mechanical properties of concrete. While ASR performance of unrestrained concrete specimens is relatively well understood, the ASR performance of concrete structures is complicated by co-acting stresses. This paper investigates the influence of sustained multiaxial stresses on the response of concrete undergoing ASR. Reactive concrete cube specimens (with three replicates) were subjected to different stress states, from no-stress to triaxial stress, and were subjected to accelerated curing until the exhaustion of expansion potential. The specimens were periodically core-drilled and the cores were tested for compressive strength and modulus of elasticity. Stress state influenced the degradation of mechanical properties and ASR-affected concrete behaved as an orthotropic material. ASR cracking was portrayed along three mutually perpendicular planes of multiaxially loaded concrete by performing damage rating index analysis. Surface cracking was also monitored. Triaxial confinement contributed to having reduced volumetric expansion and less cracking.