Dispersion of plant pulp in concrete and use thereof

摘要

Pulp fibers derived from wood or non-wood plants or recycled paper products, which are about 0.1-30 mm long and about 0.001-0.1 mm in diameter with length-to-diameter ratio of about 30-3000, are dispersed in conventional concrete mixtures using conventional mixing equipment for effectively improving fresh and hardened concrete properties at relatively low cost. Dispersion is achieved by individualizing the plant pulp fibers so that they are not fully bonded to each other, and dispersing the individual fibers in concrete at relatively low dosages of about 0.3-30 kg per cubic meter. Once individualized, the affinity of plant pulp fibers for water facilitates their dispersion in conventional concrete mixtures. Fresh concrete mixtures incorporating the dispersed individualized plant pulp fibers possess desirable workability, resistance to segregation and bleeding, pumpability, finishability, and reduced rebound when pneumatically applied. Hardened concrete materials incorporating the dispersed individualized plant pulp fibers provide improved crack resistance, toughness characteristics, impact resistance, fatigue life, abrasion resistance, and other mechanical, physical and durability characteristics. Precast and cast-in-pace concrete as well as plain and reinforced concrete and shotcrete benefit from such improvements in fresh and hardened material properties rendered by dispersed plant pulp fibers.