Patent ID: 6569526
Filing Date: 2003-05-27
Classification: C04B,C08J,D01D,E04C,Y10T

Abstract:
Fibers for reinforcing a concrete composition, comprising: a plurality of individual fiber bodies having an elongated length defined between two opposing ends and comprising at least one synthetic polymer, said individual fiber bodies having surfaces that are substantially free of stress fractures induced by mechanical-flattening of the fiber bodies between opposed rollers, said individual fiber bodies being substantially nonfibrillatable into smaller fiber units after mixing in wet concrete to the extent necessary to achieve substantially uniform dispersal of the fibers therein, and said fiber bodies having a generally quadrilateral cross-sectional profile along said elongated length, thereby having width, thickness, and length dimensionswherein the average width is no less than 1.0 mm; wherein the average width is no more than 5.0 mm; wherein the average thickness is no less than 0.05 mm; wherein the average thickness is no more than 0.2 mm; wherein the average length is no less than 20 mm; wherein the average length is no more than 75 mm; wherein said fiber bodies have a Young's modulus of elasticity no less than 4 Giga Pascals; wherein said fiber bodies have a Young's modulus of elasticity no more than 20 Giga Pascals; wherein said fiber bodies have a tensile strength no less than 400 Mega Pascals; wherein said fiber bodies have a tensile strength of no more than 1600 Mega Pascals; wherein said fiber bodies have a minimum load carrying capacity in tension mode no less than 20 Newtons per fiber body; wherein said fiber bodies have a minimum load carrying capacity in tension mode no greater than 1000 Newtons per fiber body; wherein said fiber bodies have an average square area to volume ratio no less than 10.5 mmâˆ’1; wherein said fiber bodies have an average square area to volume ratio no more than 42 mmâˆ’1; wherein said fiber bodies have an average bendability â€œBâ€  nor less than 100 mNâˆ’1*mâˆ’2; and wherein said fiber bodies have an average bendability â€œBâ€  not more than 2500 mNâˆ’1*m2; said bendability â€œBâ€  of said fibers being determined in accordance with the formula, B=1/(3Â·EÂ·I), wherein the moment of inertia â€œIâ€  for a generally quadrilateral is computed in accordance with the formula, I={fraction (1/12)}Â·wÂ·t3, wherein â€œwâ€  is the average width and â€œtâ€  is the average thickness of the generally quadrilateral cross-section.