Figure 5: Bond strength of restrained bars as a function of slip Figure 4: Bond strength of simple bar as a function of slip

It is indicated in Figure 4 that the bond strength between the steel bar and HAC concrete of the prestressed members (B1F), is a bit higher than that of those non-prestressed ones, because the prestressed bar is compressed by the surrounding concrete. When it is cut, the bond strength in the female cone (B1), is still higher than that in B1F, because the former

is forced in three dimensions (Figure 6). The prestressed bar was stretched while the slide between the HAC concrete anchorage and the block around was begun.