Evaluation of fatigue damage on the mechanical properties of fiber reinforced cement pastes

✍ Scribed by H. Nayeb Hashemi; M.D. Cohen; T. Erturk

• Publisher: Elsevier Science
• Year: 1985
• Tongue: English
• Weight: 721 KB
• Volume: 15
• Category: Article
• ISSN: 0008-8846
• DOI: 10.1016/0008-8846(85)90155-3

✦ Synopsis

Type III Portland cement samples reinforced with 0.01 volume fraction of chopped steel fibers were subjected to cyclic loading in tension with zero minimum stress and maximum stress amplitudes varying from 0.72 to 1.38 of the first crack strength of the composite.

The number of cycles-to-fracture at different stress amplitudes (S-N curve) indicated good fatigue resistance in stress amplitudes representing up to 80% of the range between first crack and ultimate composite strengths. A number of specimens cycled at a stress amplitude 38% above the first crack strength were monotonically fractured in tension following different levels of prior fatigue damage. Pre-cycled specimens exhibited a rapid drop in Young's modulus, substantial increase in ultrasonic attenuation, but insignificant decay in composite strength and post-cracklng ductility.

It was concluded that fatigue damages, short of propagating interface cracks to the ends of the fibers, would not adversely affect the composite strength and post-cracking fiber pull-out behavior.