Important Information and General Notes
General Instructions for the Designer
These general instructions for the designer are provided to ensure the proper selection and installation of Simpson Strong-Tie® products and must be followed carefully. They 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.
- The term “Designer” used throughout this catalog 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 and must have sufficient strength (bending, shear, etc.) to resist the loads imposed by the anchors.
- When the allowable stress design method is used, the design service load shall not exceed the published allowable loads reduced by load-adjustment factors for temperature, spacing and edge distance. Where stated in this catalog, allowable loads may be increased 33 1/3% when permitted by code. In general, this is permissible only when the alternative basic load combinations of the IBC are used.
- When the strength design method is used, the factored loads shall not exceed the design strengths calculated in accordance with the published design data.
- Simpson Strong-Tie strongly recommends the following addition to construction drawings and specifications: “Simpson Strong-Tie products are specifically required to meet the structural calculations of plan. Before substituting another brand, confirm load capacity based on reliable published testing data or calculations. The Engineer/Designer should evaluate and give written approval for substitution prior to installation.”
- Where used in this catalog, “IBC” refers to the 2012 International Building Code, and “ACI 318” refers to ACI 318-11 Building Code Requirements for Structural Concrete. Local and/or regional building codes may require meeting special conditions. Building codes often require special inspection of anchors. For compliance with these requirements, contact the local building authority. Except where mandated by code, Simpson Strong-Tie products do not require special inspection.
- Allowable loads and design strengths are determined from test results, calculations and experience. These are guide values for sound base materials with known properties. Due to variation in base materials and site conditions, site-specific testing should be conducted if exact performance in a specific base material at a specific site must be known.
- Unless stated otherwise, tests conducted to derive performance information were performed in members with minimum thickness equal to 1.5 times the anchor embedment depth. Anchoring into thinner members requires the evaluation and judgment of a qualified Designer.
- Tests are conducted with anchors installed perpendicular (±6°) from a vertical reference to the surface of the base material. Deviations can result in anchor bending stresses and reduce the load-carrying capacity of the anchor.
- Allowable loads and design strengths do not consider bending stresses due to shear loads applied with large eccentricities.
- Metal anchors and fasteners will corrode and may lose load carrying capacity when installed in corrosive environments or exposed to corrosive materials. See Supplemental Topic G3.
- Mechanical anchors should not be installed into concrete that is less than 7 days old. The allowable loads and design strengths of mechanical anchors that are installed into concrete less than 28 days old should be based on the actual compressive strength of the concrete at the time of installation.
- Nominal embedment depth (“embedment depth”) is the distance from the surface of the base material to the installed end of the anchor and is measured prior to application of an installation torque (if applicable). Effective embedment depth is the distance from the surface of the base material to the deepest point at which the load is transferred to the base material.
- Drill bits shall meet the diameter requirements of ANSI B212.15. For adhesive anchor installations in oversized holes, see Supplemental Topic A1. For adhesive anchor installations into core-drilled holes, see Supplemental Topic A2.
- Threaded-rod inserts for adhesive anchors shall be oil-free UNC fully threaded steel. Bare steel, zinc plating, mechanical galvanizing or hot-dip galvanizing coatings are acceptable.
- Allowable loads and design strengths are generally based on testing of adhesive anchors installed into dry holes. For installations into damp, wet and submerged environments, see Supplemental Topic A3.
ACI 318 states that adhesive anchors should not be installed into concrete that is less than 21 days old. For information on adhesive anchors installed into concrete less than 21 days old, see Supplemental Topics for Anchors.
- Adhesive anchors can be affected by elevated base material temperature. See Supplemental Topic A4.
- Anchors are permitted to support fire-resistant construction provided at least one of the following conditions is fulfilled: (a) anchors are used to resist wind or seismic forces only; (b) anchors that support gravity-load-bearing structural elements are within a fire-resistive envelope or a fire-resistive membrane, are protected by approved fire-resistive materials, or have been evaluated for resistance to fire exposure in accordance with recognized standards; or (c) anchors are used to support non-structural elements.
- Exposure to some chemicals may degrade the bond strength of adhesive anchors. Refer to the product description for chemical resistance information or refer to the topic "Chemical Resistance of Adhesive Anchors" under Supplemental Topics for Anchors.