Tests have been conducted with a small opening enclosed by reinforcement and introduced into a region subjected to predomi- nant shear [4,9–12]. As shown in Fig. 3, the beam may fail in two distinctly different modes. The first type is labelled beam-type fail- ure which is typical of the failure commonly observed in solid beams except that the failure plane passes through the centre of the opening (as shown in Fig. 3a). Conversely, in the second type labelled frame-type failure, the formation of two particular diago- nal cracks, one in each member bridging the two solid beam seg- ments, leads to the failure (as shown in Fig. 3b). It was suggested that these types of failures require separate treatment for complete design [6].