Method of incorporating multifilament strands of carbon fibers into cement to produce reinforced structures having improved flexural strengths

A process for producing a carbon fiber-reinforced cementitious structure having improved flexural strength which comprises filling a mould with a cementitious mix to a desired level so as to form a first layer, impregnating multifilament strands of carbon fiber with a liquid hydrophobic resin system, arranging said impregnated strands in substantially parallel rows along a length of the mould in contact with the surface of said first layer of cement, adding a second layer of the cementitious mix to said first layer while said first layer is still in the uncured condition and in such manner that the cementitious mix of said second layer also contacts said impregnated strands thereby to enclose the same in cement, and simultaneously curing the hydrophobic resin and cementitious mix to produce said carbon fiber-reinforced cementitious structure.