| Abstract: | This paper describes a study of the processes involved at and near the steel-matrix interface when an embedded steel wire is pulled out of a cement paste or mortar matrix. Prior to debonding, shrinkage leads to micro-cracking of the matrix which in turn reduces the stress transfer at the interface. The behaviour after debonding, which constitutes the major part of the study, is again markedly non-linear. This arises from compaction of the cement paste in the vicinity of the wire and is produced by the pull-out process itself. The compaction is more marked with rougher wires and occurs to a greater degree with cement paste than with mortars. |
