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Design Earthquake <br />Load Combinations <br />(4-2) <br />LRFD Specification <br />(A4-1) through (A4-6 <br />~oQE <br />Design Basis Ground Motion <br />Eqs. (4-1) and Chapter 16 Eqs. (12-17) and (12-18) <br />respectively <br />Section Eqs. Chapter 16 Eqs. (12-1) through (12-6) <br />respectively <br />Em <br />Section 7-5-187: ASIC SEISMIC PROVISIONS. The text of part 1, section 1 of the <br />AISC Seismic Provisions is deleted and replaced with the following: <br />1. Scope <br />These provisions are intended for the design and construction of structural steel <br />members and connections in the Seismic Force Resisting Systems in buildings for <br />which the design forces resulting from earthquake motions have been determined <br />on the basis of various levels of energy dissipation in the inelastic range of <br />response. These provisions shall apply to buildings in Seismic Zone 2 with an <br />importance factor I greater than one, in Seismic Zone 3 and 4 or when required by <br />the Engineer of Record. <br />These provisions shall be applied in conjunction with, Chapter 22, Division II, <br />hereinafter referred to as the LRFD Specification. All members and connections <br />in the Lateral Force Resisting System shall have a design strength as provided in <br />the LRFD Specification to resist load combinations 12-1 through 12-6 (in Chapter <br />16) and shall meet the requirements in these provisions. <br />Part I includes a Glossary, which is specifically applicable to this Part, and .Appendix S. <br />Section 7-5-188: LOAD COMBINATIONS. Part I, Section 4.1, first paragraph of the AISC <br />Seismic Provisions is deleted and replaced as follows: <br />4.1 Loads and Load Combinations <br />The loads and load combinations shall be those in Section 1612.2 except as modified throughout <br />these provisions. <br />Eh is the horizontal component of earthquake load E required in Chapter 16. <br />Where required in these provisions, an amplified horizontal earthquake load S2oEh <br />shall be used in lieu of Eh as given in the load combinations below. The term S2o is <br />the system overstrength factor as defined in chapter 16. The additional load <br />combinations using amplified horizontal earthquake load are: <br />1.2 D + 0.5 L + 0.25 + S2oEh (4-1) <br />0.9 D + S2oEh (4-2) <br />10 <br />