(a)
(b)
Figure 49: Cross-sectional stress profile of the stone slab with NSM screw-thread steels. (a) The cross section stress profile of brittle failure mode: (A) elastic phase before cracking and (B) failure phase after cracking. (b) The cross section stress profile of ductility failure mode: (A) elastic phase before cracking, (B) from the appearance of crack to yielding of screw-thread steels after cracking, and (C) failure phase.