2.3 CORROSION
2.4 . SEISMIC CONSIDERATIONS
Direct Fastening Technical Guide , Edition 24
2.3 CORROSION
Refer to the Hilti Corrosion Handbook for information regarding sources of potential corrosion and corrosion protection of fasteners .
The following graphs allow for a comparison between the cyclic behavior and the static monotonic reference test .
2.4 . SEISMIC CONSIDERATIONS
2.4.1 STRUCTURAL SYSTEMS
Historically , power-actuated fasteners ( Hilti DX and GX fastening systems ) have been used in seismic and non-seismic regions for structural and nonstructural applications . Reference Section 3.1.3 of this Product Technical Guide for an overview on typical direct fastening applications .
Structural system applications may involve construction of lateral force resisting systems such as shear walls and untopped and concrete filled steel deck roof and floor diaphragms as described in this Product Technical Guide Sections 3.2.8 and 3.5 respectively . Lateral force resisting systems are designed to resist the controlling load combinations involving wind and seismic forces and are a critical component of the overall building structure . Power-actuated fastening systems are used for steel deck roof and floor diaphragm frame attachments and shear wall sheathing attachments to cold-formed steel framing members . Screw fasteners are also an integral part of the lateral force resisting systems when used as structural frame and sidelap connections in diaphragms , as well as framing connections for cold-formed steel stud and track wall components . The American Iron and Steel Institute ( AISI ) S100 North American Cold-Formed Steel Specification ; AISI S213 North American Standard for Cold-Formed Steel Framing – Lateral Design ; and AISI S310 North American Standard for the Design of Profiled Steel Diaphragms provide design provisions and safety and resistance factors for these structural systems used to resist wind and seismic forces . These structural systems involve redundant fastenings in orthogonal directions and are qualified by large scale diaphragm and shear wall assembly tests using either quasi-static or cyclic loading protocols .
Extensive seismic research into untopped steel deck diaphragms has been conducted at McGill University and Ecole Polytechnique by Tremblay , Rogers , et al . and was supplemented by Hilti with additional testing . This research has proven that mechanical fasteners , such as power-actuated fasteners and screws , provide improved seismic ductility and energy dissipation when compared to traditional arc spot puddle welds .
Structural system seismic research investigating shear walls has been conducted by AISI , the American Plywood Association ( APA ) and university researchers . This research was codified in the International Building Code ( IBC ) and National Building Code of Canada ( NBCC ) in AISI S213 . ICC-ES AC230 Acceptance Criteria for Power-Driven Pins for Shear Wall Assemblies with Cold-Formed Steel Framing and Wood Structural Panels further establishes the seismic load test requirements for poweractuated fasteners used as alternatives to screw fasteners for attachment of wood structural panel sheathing to cold-formed steel framing . Cyclic load tests following the CUREE protocol , are used to simulate the seismic forces . Safety and resistance factors for wind and seismic loading are then applied to the cyclic load test results to develop the design shear loads . Energy dissipation of the shear wall assembly and a predictable post peak behavior were demonstrated through qualification testing and are critical to shear wall performance in a seismic event .
Test protocol and evaluation methods for individual fasteners installed in steel base materials have been established by ICC-ES in Acceptance Criteria 70 , Acceptance Criteria for Power Actuated Fasteners , Annex A . Successful completion of this test protocol allows for the fastener to achieve a published seismic load up to the static load level , in both tension and shear .
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