FWIW: In some new construction, Concrete slabs for buildings use steel cables instead of rebar. But the cables are first clamped and tensioned (about 30K to 50K psi is applied to the cables), then they pour in the concrete and let it hardened. The cable clamps are removed and they cut off the excess cables outside of the slabs. The cables apply internal compression to the concrete slab to increase stiffness. You would need to do something like that for the kevlar tape.