Failure modes in FRCM systems with dry and pre-impregnated carbon yarns: Experiments and modeling

In this paper, interface bond-slip relations are derived from pull out tests on multifilament carbon yarns embedded in a cementitious matrix. Two different types of yarns are investigated, dry and pre-impregnated with epoxy resin. A variational model able to reproduce the mechanisms of interface debonding and frictional slippage observed in experiments is developed, where the constitutive parameters are calibrated on the base of the experimental data available from pull out tests. The model is implemented in a finite elements code, and pull out and double shear bond tests on masonry substrates are simulated. Finally, numerical results are compared with experimental evidences.