When I worked at Akzo Nobel Arami division about 15 years ago, we did some work on concrete reinforcement with both aramid fibre and carbon fibre.
The main idea was to make a mesh type fabric that was used to repair concrete cancer where the rusting steel reinforcement was damaging the integrity of the concrete in buildings.
The fabrics were made from pultruded rods that were then laid up as a square mesh.
Concrete needs no reinforcement in compression, but it does need it in tension to prevent cracks propagating to failure.
The tensile strength of these fibres is well documented, so Google or the fibre manufacturers websites will give you the data.
Only count the fibres along the axis of the fibre. Ignore any contribution from the resin.
The fabric manufacturer should be able to provide the weight of fibre per unit of length or area of the fabric. From this you can calculate the cross sectional area of the fibre to do the tensile strength of the fabric calculations.
Regards
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