Abstract: In a column base joint structure, an anchor bolt and a column installed upright on a groundsel are tightly joined using groundsel-side and column-side hardware pieces. The groundsel-side hardware piece includes groundsel-embedded and upper fitting tenon portions. A fitting hole for the upper fitting tenon portion of the groundsel-side hardware piece is formed in a base of the column. The column-side hardware piece includes a lower projecting portion projecting downward from a top face portion to the inside of the fitting hole, and a column-embedded portion positioned above the top face portion. A pin locking hole in the upper fitting tenon portion of the groundsel-side hardware piece and a pin locking hole in the lower projecting portion of the column-side hardware piece are mutually aligned, a driftpin is hammered into the aligned pin locking holes, and the anchor bolt and the column are thereby tightly joined to each other.

Abstract: A nut comprises a metal member including a nut body having an internally threaded portion formed therein and an extension formed on one end of the nut body so as to surround an opening of the internally threaded portion, the metal member being subjected to surface treatment; and a ring member made of a synthetic resin, having an outer peripheral portion united with an inner side of the extension and having a ring inner diameter substantially equal to a minor diameter of the internally threaded portion, the outer peripheral portion being united with the inner side of the extension by insert-molding using the metal member as an insert; wherein the extension has at least one recess formed in an inner portion, and the outer peripheral portion has a rotation-preventing portion fit into the at least one recess, the rotation-preventing portion being formed by the insert molding.

Abstract: A beam-column connection structure is formed, after installing a continued beam member to a predetermined position, by connecting and fixing lateral beam members, to side faces of an end portion of the continued beam member using a drift pin while connection grooves are fitted to side face connection metal fittings which are attached to the end portion, connecting an extension beam member to the end portion of the continued beam member using a drift pin while a connection groove formed at an end face of the extension beam member is fitted to the end face connection metal fitting, and connecting and fixing column members, to the upper face and lower face of the end portion of the continued beam member using a drift pin while fitting holes, formed at end faces of the column members, are fitted to the top end side portions of column connection pole-like fittings.

Abstract: A beam-column connection structure is formed, after installing a continued beam member to a predetermined position, by connecting and fixing lateral beam members, to side faces of an end portion of the continued beam member using a drift pin while connection grooves are fitted to side face connection metal fittings which are attached to the end portion, connecting an extension beam member to the end portion of the continued beam member using a drift pin while a connection groove formed at an end face of the extension beam member is fitted to the end face connection metal fitting, and connecting and fixing column members, to the upper face and lower face of the end portion of the continued beam member using a drift pin while fitting holes, formed at end faces of the column members, are fitted to the top end side portions of column connection pole-like fittings.