material developed a dense structure and a good correlation was observed between mechanical strength and total porosity . The results reported in this paper are consistent with the observations of [20–22]; the bond between ribbed steel bars and concrete,together with both compressive and tensile strengths, increase with the increasing duration of the thermal curing in wet conditions . However, the increase in energy consumption needs to be considered and it may not be economic in practice. This is discussed in Section 3.5.