Title:
Flexural Fatigue Strength of Steel Fiber Reinforced Concrete
Author(s):
V. Ramakrishnan, Gary Oberling, and Peter Tatnal
Publication:
Symposium Paper
Volume:
105
Issue:
Appears on pages(s):
225-246
Keywords:
compression tests; cracking (fracturing); fatigue tests; fiber reinforced concretes; flexural strength; flexural tests; metal fibers; static tests; workability; Materials Research
DOI:
10.14359/2143
Date:
12/1/1987
Abstract:
Results of an experimental investigation to determine the flexural fatigue strength of concrete reinforced with collated hooked-end steel fibers are presented. The performance of fresh concrete and the elastic and mechanical properties of hardened concrete are compared for concretes with and without fibers. The test program included 1) flexural fatigue and endurance limit; 2) static flexural strength including load-deflection curve, determination of first-crack load, and toughness index; 3) compressive strength; 4) static modulus; 5) pulse velocity; 6) unit weight, workability, and finishability of fresh concrete. The complete series of tests was run for two concentrations of fibers. Special care was taken to insure consistency with cement, aggregates, admixtures, procedure, and mix temperatures. There was no "balling" or tangling of the fibers during mixing and placing. Fiber reinforced concretes had better finishability and were easy to work with even at higher fiber concentrations. Due to the addition of fibers, the ductility and the post-crack energy absorption capacity were greatly increased. There was a tremendous increase in the static flexural strength and a very significant increase in the flexural fatigue strength. When compared to plain concrete, there was a considerable improvement in the endurance limit (for 2 million cycles).