Title:
Physical Properties of Concrete with Vitrified Coarse
Aggregate
Author(s):
Daniel C. Jansen, Shane M. Palmquist, Christopher Swan, Dalia Al-Mufarrej, Behnam Arya,
and Christian O. D'Annunzio
Publication:
Materials Journal
Volume:
97
Issue:
3
Appears on pages(s):
360-366
Keywords:
aggregates; compressive strength; durability; fracture proper-ties;
modulus of elasticity; Poisson ratio.
DOI:
10.14359/4628
Date:
5/1/2000
Abstract:
This study examines the potential of using vitrified aggregate in con-crete by comparing concrete made with natural coarse aggregate to concrete made with vitrified aggregate. For comparison purposes, volume fractions of cement, water, fine aggregates, and coarse aggre-gates are identical for both batches of concrete. Mechanical properties determined include compressive strength, tensile strength, fracture toughness, modulus of elasticity, Poisson ratio, density, and axial and lateral strains at peak stress. Salt scaling resistance, a durability prop-erty, is also examined. An environmental scanning electron microscope is used to explore the bond between the natural aggregate and mortar and the vitrified aggregate and mortar. Results show that at the microstructural level, the surface of the vitrified coarse aggregate is smooth in comparison with the surface of the natural coarse aggregate and that the physical bond between the vitrified coarse aggregate and mortar is poor. The poor bond result-ed in a decrease in compressive and tensile strengths and fracture ener-gy and correlated to a decrease in salt scaling resistance. An insignif-icant change in fracture toughness was found. A relatively large com-pressive modulus of elasticity was found for concrete with vitrified aggregates attributable to the stiffness of the vitrified aggregate; how-ever, the elastic modulus from bending of fracture beams showed sig-nificantly less increase in elastic modulus.