Title: Fatigue of Reinforced Silica Fume Concrete Beam Under the Environment of Water or Chloride Solution
Author(s): N. Takagi, M. Ikeda, and T. Kojima
Publication: Symposium Paper
Appears on pages(s): 1229-1250
Keywords: chlorides; corrosion; cracking (fracturing); fatigue (materials); marine atmospheres; reinforced concrete; reinforcing steels; silica fume; shear properties; Materials Research
The fatigue life of reinforced concrete beams decreases generally when tested under the environment of water. Beams in which fatigue breaks main reinforcing bars in the room condition sometimes fail in shear compression of concrete under water. It is suggested that the development and propagation of cracks in shear span are accelerated by the existence of water. It can be predicted that silica fume concretes may be effective in increasing the fatigue life under the environment of water or seawater because of high density and low permeability. The effect of silica fume on the fatigue of reinforced concrete beams under the environment of tap water or chloride solution was investigated. Two types of beam were used. Type 1 is the sound beam without corroded steel bar, and Type 2 is the deteriorated beam with corroded steel bar. Through the incorporation of silica fume, the fatigue life of beams increased for both types. The effect of silica fume was also observed in the crack pattern in the shear span of concrete. It was almost the same as that tested in the room condition, while the diagonal cracks developed quickly, and its inclination was very steep in the beam without silica fume. When the deterioration due to chloride corrosion was relatively small, the influence of corroded steel bar on the fatigue life of reinforced concrete beam was not observed.