Self-interlocking reinforcement fibers

Abstract

The invention's first embodiment uses shape memory alloy (SMA) fibers that are blended into a concrete composite material as straight fibers and are made to deform themselves and anchor and interlock themselves after dispersement in the composite material resulting in a more evenly distributed and interlocked fiber reinforcement of the cementitious material. A self-shaping fiber can be imparted to the concrete material by making the fibers out of SMA such as nickel-titanium alloy known as nitinol where the cementitious composite material mixture is briefly heated above the 'transition' temperature prior to hardening that causes the fibers to change shape. Nitinol fibers are used alone in place of conventional steel fibers. A second embodiment uses conventional coiled metal steel fiber combined with a SMA clip for retaining the coiled metal fiber during the blending of this clipped fiber into a cementitious material with required heating yielding a shape change of the coiled metal fibers ultimately resulting in improved reinforcement characteristics.