A new technique to identify the residual strength in the post-cracking regime has been developed at the Politecnico di Milano for thin-walled Fibre Cementitious Composite structures. The idea is that to spatially uncouple compressive stresses from tensile stresses in an indirect tensile test, close to Brazilian test, by introducing only a mode I crack opening. The uncoupling caused by a double notch allows the test procedure to identify the real toughness associated to fibre pull-out. The identification of in plane strength vs. crack opening for shear and diffusion stress states, especially for oriented cast flows favoured by self compacting mixes, suggests the use of this new technique that can be also easily coupled to bending tests. In this paper the main experimental details will be discussed, while in a companion paper the reliability of the identification procedure with reference to bending tests on self compacting fiber reinforced concrete for different casting procedures is investigated.