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Eh is the horizontal component of earthquake load E required in Chapter 16. <br />Where required in these provisions, an amplified horizontal earthquake load Q Eh <br />shall be used in lieu of Eh as given in the load combinations below. The term Q,, is <br />the system overstrength factor as defined in chapter 16. The additional load <br />combinations using amplified horizontal earthquake load are: <br />1.2D+0.5L+0.2S+QoEh (4-1) <br />0.9 D + Q,,Eh (4-2) <br />Exception: the load factor on L in load combination 4-1 shall be equal to <br />1.0 for garages, areas occupied ass places of public assembly and all areas <br />where the live load is greater than 100 psf. <br />Orthogonal earthquake effects shall be included in the analysis as required in section 1633.1, <br />except that, when consideration of the load Q,,Eh is required, orthogonal earthquake effects need <br />not be considered. <br />Section 7-5-189: BASIC LOAD COMBINATIONS. Section 1612.2.1 of the Code is <br />deleted and replaced with the following: <br />1612.2.1 Basic load combinations. Where Load and Resistance Factor Design (Strength Design) <br />is used, structures and all portions thereof shall resist the most critical effects from the following <br />combinations of factored loads: <br />1.4D <br />(12-1) <br />1.2D+ 1.6L+0.5 (L,orS) <br />(12-2) <br />1.2D+1.6(L,orS)+(f,Lor0.8W) <br />(12-3) <br />1.2D + 1.3 W + (f, L + 0.5 (L, or S) <br />(12-4) <br />1.2D+1.0E+(f1L+f2S) <br />(12-5) <br />0.9D ± (I.OpEh or 1.3 99 <br />(12-6) <br />1.� <br />f, = 1.0 for floors in places of public assembly, for live loads in excess of 100 psf (4.9 <br />kN/m2 ), and for garage live load. <br />= 0.5 for other live loads. <br />f2 = 0.7 for roof configurations (such as saw tooth) that do not shed snow off the <br />structure. <br />= 0.2 for other roof configurations. <br />EXCEPTIONS: <br />Factored load combinations for concrete per Section 1909.2 where load combinations do <br />not include seismic forces. <br />