An experimental study of the bond behavior of twisted steel bars embedded in mortar cylinders and in the joints of masonry wallettes

Among the different strengthening techniques available to reinforce masonry buildings, the near-surface mounted technique consists in inserting reinforcing elements of high-strength material in grooves realized by removing part of the mortar in the horizontal bed joints of a masonry wall. The present study deals with two experimental campaigns on pull-out tests conducted on twisted steel bars embedded concentrically in mortar cylinders and in the mortar bed joints of masonry wallettes as in in-situ applications. In order to compare the results between cylindrical and masonry specimens, the same bonded lengths are considered.