In all-wood-type wooden check dam in Akita Prefecture, lag screws and deformed steel bar are utilized as the connectors. From many failure tests of wooden check dams, it was confirmed that the structures with these connectors have very high strength for pull -out and shear behavior. Recently, general purpose utilization of lag screw and deformed steel bar to other wooden civil engineering structures is considered. However there are few examples reviewed pull-out strength of lag screws and deformed steel bar. Therefore, in this study, we conducted many pull-out test of lag screw and deformed steel bar with different pre-drilled hole diameter, and we tried formulization of each pull-out strength.
