摘要 |
A building structure including a first building member and a second building member may be connected by fasteners, each fastener having a head, a tapered lead portion having an angle from 30 to 60° of at least HRC 50 hardness adapted to start into a pilot hole, a thread-forming portion of at least HRC 50 hardness adapted to thread the fastener into at least the second steel building member, and a threaded portion having a through hardness from about HRB 70 to HRC 40, such that the fastener is capable of providing a ratio of failure torque to thread-forming torque of at least 3.0 and a ratio of failure torque to drive torque greater than 10 when the second steel building member has a thickness of about 0.25 inch and the pilot hole has at least one diameter within nominal diameter from 80 to 98% of major diameter. |