Notes to Table 4.1.8.18.:
4.1.8.22. Supplemental Energy Dissipation Design Considerations (1) The values of storey shears, storey forces, member forces, and deflections for the design of all structural framing elements and all supplemental energy dissipation devices shall be obtained from analysis conforming to Sentence 4.1.8.21.(4) using one of the following values, whichever produces the most critical effect: (a) mean plus IE times the standard deviation of the results of all Non-linear Dynamic Analyses, or (b)   times the mean of the results of all Non-linear Dynamic Analyses. (2) The largest interstorey deflection at any level of the structure as determined in accordance with Sentence (1) shall conform to the limits stated in Sentence 4.1.8.13.(3). (3) The force-deformation and force-velocity characteristics of the supplemental energy dissipation devices used in the analysis and design of structures with supplemental energy dissipation systems shall be validated by testing at least two full-size specimens of each type of supplemental energy dissipation device. (4) The force-deformation and force-velocity characteristics and damping values of a representative sample of the supplemental energy dissipation devices installed in the building shall be validated by tests prior to their installation. (5) Elements of the supplemental energy dissipation system, except the supplemental energy dissipation devices themselves, shall be designed to remain elastic for the design loads. (6) All structural framing elements shall be designed, (a) for an SFRS with Rd
=1.0, using the forces referred to in Sentence (1) with RdRo
= 1.0, except that the SFRS shall be detailed in accordance with the requirements for Rd ≥ 1.5 and the applicable referenced design standards, or (b) for an SFRS with Rd
> 1.0, using the forces referred to in Sentence (1) with RdRo
= 1.0, except that the SFRS shall be detailed in accordance with the requirements for the selected Rd and the applicable referenced design standards. (7) Supplemental energy dissipation devices and other components of the supplemental energy dissipation system shall be designed in accordance with Sentence (1) with consideration of the following: (a) low-cycle, large-displacement degradation due to seismic loads, (b) high-cycle, small-displacement degradation due to wind, thermal, or other cyclic loads, (c) forces or displacements due to gravity loads, (d) adhesion of device parts due to corrosion or abrasion, biodegradation, moisture, or chemical exposure, (e) exposure to environmental conditions, including, but not limited to, temperature, humidity, moisture, radiation (e.g., ultraviolet light), and reactive or corrosive substances (e.g., salt water), (f) devices subject to failure due to low-cycle fatigue must resist wind forces without slip, movement, or inelastic cycling, (g) the range of thermal conditions, device wear, manufacturing tolerances, and other effects that cause device properties to vary during the design life of the device, and (h) connection points of devices must provide sufficient articulation to accommodate simultaneous longitudinal, lateral, and vertical displacements of the supplemental energy dissipation system. (8) Means of access for inspection and removal for replacement of all supplemental energy dissipation devices shall be provided. Section 4.2. Foundations 4.2.1. General