Impact of processed cellulose fibers on portland cement concrete properties

Processed cellulose fibers provide a desirable balance between mechanical, physical, and durability characteristics when placed in a cement matrix. The effect of processed cellulose fibers (natural) on the mechanical properties and dimensional stability properties of portland cement concrete and its subsequent use in the paving industry are studied. The mechanical and durability properties of three concrete mixtures [the standard Department of Transportation (DOT) mixtures for pavement construction and full-depth patch repair] with and without processed cellulose fibers were studied. The test results are very promising. There is a 10 percent improvement in compressive strength and a 40 percent improvement in impact strength of cellulose fiber concrete when compared with plain cement concrete mixtures. The average cellulose fiber concrete's flexural strength after 24 hours was 3 MPa and the average 28-day flexural strength was 5 MPa. The inclusion of fibers shows a marginal improvement in fracture toughness of the concrete. Inspecting the abrasion and F-T data illustrates the beneficial effects of fibers in plain concrete. The mechanical properties of the two field mixtures are similar at early ages. However, the modified fiber-reinforced concrete mixture exhibits superior 28-day strength properties in spite of a 17 percent reduction in cement content and a 5 percent increase in the water-to-cement ratio. The improved reinforcing properties of processed cellulose fibers can be attributed to their crack suppression and stabilization characteristics.