These general instructions for the designer are provided to ensure proper selection and installation of Simpson Strong‑Tie Company Inc. products and must be followed carefully. These general instructions are in addition to the specific design and installation instructions and notes provided for each particular product, all of which should be consulted prior to and during the design process.
- Design for Strong Frame® moment frames are in accordance with the following:
- 2018, 2015, 2012 and 2009 International Building Code
- AISC Specification for Structural Steel Buildings (ANSI/AISC 360‑10, 360-16)
- AISC Seismic Provisions (ANSI/AISC 341‑10, 341-16)
- RCSC Specification for Structural Joints Using ASTM A325 or A490 Bolts
- Building Code Requirements for Structural Concrete (ACI 318-11, ACI 318-14)
- AISC Prequalified Connections for Special and Intermediate Steel Moment Frames for Seismic Applications (ANSI/AISC 358-16)
Moment frames are designed using Load and Resistance Factored Design (LLRFD) methodology for determining frame drift and strength limits. Allowable Stress Design (ASD) shear is determined as VASD = 0.7 x VLRFD for seismic load combinations and VASD = VLRFD/1.6 for wind load combinations.
- Building codes have specific design requirements for use of steel moment frames. Designer shall verify structural design meets the applicable code requirements. Contact Simpson Strong‑Tie for more information.
- Strong Frame moment frames provide a key component of a structure’s lateral force resisting system only when incorporated into a continuous load‑transfer path. The designer must specify the required components of the complete load transfer path including diaphragms, shear transfer, chords and collectors and foundations.
- The term “designer” used throughout this design guide is intended to mean a licensed/certified building design professional, a licensed professional engineer or a licensed architect.
- All connected members and related elements shall be designed by the designer.
- All installations should be designed only in accordance with the allowable load values set forth in this design guide.
- Local and/or regional building codes may require meeting special conditions. Building codes often require special inspection of anchors installed in concrete and masonry. For compliance with these requirements, it is necessary to contact the local and/or regional building authority. Except where mandated by code or code listed, Simpson Strong‑Tie® products do not require special inspection.
- High‑strength bolts in fully pretensioned Yield-Link stemto-beam flange connections may require special inspection to verify installation pretension. For compliance with these requirements, it is necessary to contact the local and/or regional building authority. Where applicable, Direct Tension Indicating (DTI) washers or twist-off-type bolts are included in the Strong Frame installation kits to verify installation pretension. Contact Simpson Strong‑Tie for Fastener Assembly Certificates of Conformity.
- Welding shall be in accordance with AWS D1.1 and AWS D1.8 (as applicable for seismic). Welds shall be as specified by the designer. Provide welding special inspection as required by local building department.
- Holes in base plates are oversized holes for erection tolerance. Designer must evaluate effects of oversized holes and provide plate washer with standard-size holes welded to base plate where required.
- Design of Strong Frame moment frames assumes a pinned condition at the base of columns. Fixed base design option available, contact Simpson Strong-Tie for more information.