Effect of fiber addition on fresh and hardened properties of spun cast concrete.

The effect of fiber addition on the properties of fresh and hardened concretes casted by centrifugation was investigated. Workability of fresh concrete mixtures, sludge bleeding after centrifuging, and mechanical properties of hardened concrete including compressive and splitting tensile strengths and modulus of elasticity were examined. Post-crack behavior of spun cast concrete was investigated by splitting tensile testing. Considering sanitary sewer environments, concrete resistances against sulfuric acid erosion and sulfate expansion were evaluated. Although the addition of low fiber fractions (below 0.15 vol.%) did not significantly affect workability and strength of the spun cast concretes, it enhanced their toughness and resistance against sulfate expansion. [ABSTRACT FROM AUTHOR]