Title: Mechanical Properties, Durability and Performance in Hydrocarbon Fire of High-Strength, Semi-lightweight Concrete

Author(s): A. Bilodeau, R. Chevrier, V. M. Malhotra and G. C. Hoff

Publication: Symposium Paper

Volume: 170

Issue:

Appears on pages(s): 1157-1196

Keywords: Chlorides; concretes; freeze thaw durability; high-strength concrete; hydrocarbons; lightweight concrete; mechanical properties; silica fume.

DOI: 10.14359/6872

Date: 7/1/1997

Abstract:
air-entrained concretes were made using a silica fume blended cement and six lightweight aggregates having a wide range of absorption values. The properties of the fresh concrete, including the autogenous temperature rise were determined. Concrete specimens were subjected to the determination of the compressive, flexural and splitting-tensile strengths, Young’s modulus of elasticity and drying shrinkage; the resistance to the freezing and thawing cycling, chloride-ion penetration and carbonation were also determined. The tests for the freezing and thawing resistance were performed on concretes made using dry and saturated lightweight aggregates. Small reinforced concrete beams made using three of the lightweight aggregates, and some incorporating polypropylene fibres, were tested for hydrocarbon-fire resistance. The target compressive strength at 28 days (60 to 65 MPa) was generally reached with five of the lightweight aggregates used. As expected the mechanical properties of the concrete were somewhat related to the degree of absorption of the lightweight aggregates. All the concretes investigated demonstrated excellent resistance to chloride-ion penetration at 28 days, negligible depth of carbonation after 448 days of air drying, and excellent performance in the freezing and thawing cycling. Based on the visual evaluation, the use of the polypropylene fibres improved considerably the performance of the high-strength semi-lightweight concrete in hydrocarbon fire.