INTERACTION OF SILICA FUME AND POLYPROPYLENE FIBERS IN HIGH PERFORMANCE CONCRETE

摘要

Silica fume and polypropylene fibers can enhance mechanical properties and durabilityrnof concrete mixtures. However, there has been relatively little work tackling the interaction betweenrnboth constituents when introduced to High performance concrete (HPC).rnThis paper presents part of an investigation that focuses on the short and long-term properties ofrnconcretes incorporating silica fume and fibers and highlights the contribution of each of the tworningredients. Thirty-six mixtures were prepared and fresh and hardened concrete tests were carried outrnat different ages. In addition, crack pattern was evaluated for slabs exposed to various environments.rnThis work reveals that many properties are dosage-sensitive for both the silica fume and the fibers. Inrnfact, properties such as the flexural strength and shrinkage are more dependant on one of the tworningredients than the other. New formulae are suggested herein for the prediction of the modulus ofrnrupture (MoR).