PURPOSE: To secure the high flowability, high chargeability, aggregate separation resistance and high strength of the concrete composition by adding a high performance water-reducing agent and pulp fibers and controlling the slump flow value to a ≥ a specific value.
CONSTITUTION: The high performance water-reducing agent includes a naphthalene sulfonate metal salt-formaldehyde condensation product (Mighty 150), a melamine sulfonate metal salt-formaldehyde condensation product (Mightly 150 V-2), a phenolsulfonic acid-formaldehyde condensation product, a phenol.sulfanilic acid-formaldehyde cocondensation product, an unsaturated monocarboxylic acid, and its derivative. The water-reducing agent is added in an amount of 0.3-3.0wt.% as an effective component to a cement. The pulp fibers include virgin pulp obtained from needle-leaf trees, broad-leaf trees, etc., and fibers obtained from waste paper, and are added in an amount of 0.1-5.0wt.% based on kneading water. Other cement additives (e.g. air-carrying agent) may further be added. The slump floe value (defined by JIS-A 1101) of the composition is ≥40cm.
IZUMI TATSUO
CHO TAKESHI
YAMAMURO HODAKA
TAKAHASHI SHUNSUI
