Dispersion of plant pulp in concrete and use thereof

A fresh concrete mixture incorporating dispersed cellulose pulp fibers, which is workable, pumpable, resistant to segregation and excess bleeding, possesses desirable finishability, and offers resistance to the loss of materials through rebound when pneumatically applied, the concrete mixture comprising:

• 0. 3-30 kg per cubic meter of substantially individual cellulose fibers which have been derived from a wet cellulose pulp dried under conditions to achieve a fluff pulp with reduced fiber-to-fiber bonding therein, and subsequent, mechanical separation of the dried fluff pulp into the substantially individual fibers;
• about 50-1500 kg per cubic meter of cement;
• about 50-1000 kg per cubic meter of water;
• about 100-3600 kg per cubic meter of aggregate;
• and wherein
• the substantially individual fibers are dispersed uniformly throughout the cement-based material through mixing for a sufficiently long period of time.

A hardened cellulose fiber reinforced cement structure comprising:

• about 0.3-30 kg per cubic meter of substantially individual cellulose fibers derived by initially drying a wet cellulose pulp under conditions to form a dried fluff pulp having low fiber-to-fiber bonding therein, and subsequently mechanically separating the dried fluff pulp into the substantially individual fibers;
• about 50-1500 kg per cubic meter of cement;
• about 50-1000 kg per cubic meter of water;
• about 100-3600 kg per cubic meter of aggregate;
• and
• said substantially individual cellulose fibers being uniformly dispersed throughout the hardened structure through mixing of the fibers together with the cement, water and aggregate for a sufficient length of time prior to curing.