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IBC2018 (1613), ASCE 7-16 CHAPTER 11, 12, 13 SEISMIC DESIGN CRITERIA <br />Response Spectral Acc. (0.2 sec) Ss =1.331 g Figure 22-1,22-3,22-5,22-6 <br />Response Spectral Acc.( 1.0 sec) S1 =0.476 g Figure 22-2,22-4,22-5,22-6 <br />Soil Site Class Table 20-3-1, Default = D <br />Site Coefficient Fa = 1.200 Table 11.4-1 <br />Site Coefficient Fv =1.525 Table 11.4-2 <br />Max Considered Earthquake Acc. SMS =Fa.Ss = 1.597g (11.4-1) <br />Max Considered Earthquake Acc. SM1 =Fv.S1 = 0.726g (11.4-2) <br />@ 5% Damped Design SDS =2/3(SMS)= 1.065g (11.4-3) <br />SD1 =2/3(SM1)= 0.484g (11.4-4) <br />Building Risk Categories Table 1604.5 <br />Design Category Consideration:with dist. between seismic resisting system >40ft <br />Seismic Design Category for 0.1sec D Table 11.6-1 <br />Seismic Design Category for 1.0sec D Table 11.6-2 <br />S1 < .75g NA Section 11.6 <br />Since Ta < .8Ts (see below), SDC = D Control (exception of Section 11.6 does not apply) <br />IBC, Seismic Design Category D IRC, Seismic Design Category = D2 <br />12.8 Equivalent lateral force procedure <br />Seismic Force Resisting Systems <br />Ct = 0.02 x =0.75 T-12.8-2 <br />Building ht. Hn =35 ft ited Building Height (ft) =65 <br />Cu = 1.400 for SD1 of 0.484g Table 12.8-1 <br />Approx Fundamental period, Ta = Ct(hn)x = 0.288 12.8-7 TL =6.000 Sec <br />Calculated T shall not exceed ≤Cu.Ta = 0.403 Use T =0.403 sec. <br />0.8Ts = 0.8(SD1/SDS)= 0.364 <br />Is structure Regular & ≤ 5 stories ? 12.8.1.3 <br />Response Spectral Acc.( 0.2 sec) Ss =1.331g <br />Fa = 1.20 <br />@ 5% Damped Design SDS =⅔(Fa.Ss)= 1.065g (11.4-3) <br />Response Modification Coef. R =6.5 Table-12.2-1 <br />Over Strength Factor 2.5 foot note g <br />Importance factor I =1 T 1.5-2 <br />Seismic Base Shear V =C s W <br />SDS (12.8-2) <br />R/I <br />SD1 (12.8-3) <br />(R/I).T <br />SD1TL (12.8-4) <br />T2(R/I) <br />Cs shall not be less than =0.044SDS.I≥.01 = 0.047 (12.8-5) <br />Min Cs =0.5S1I/R N/A For S1 ≥ 0.6g (12.8-6) <br />Use Cs =0.164 <br />Design base shear V =0.164 W Control <br />12.14 Simplified Seismic base shear <br />@ 5% Damped Design SDS =1.065 SDC = D Limitations:P <br />F =1.2 R = 6.5 <br />V =FSDS(W)= 0.197 W (12.14-11) <br />R <br />A. BEARING WALL SYSTEMS <br />< Ta <br />Cs ==0.164 <br />or need not to exceed, Cs == 0.185 For T≤ TL <br />or Cs =N/A For T > TL <br />For three story building <br />T-12.1 <br />T-12.2 <br />T-R301.2.2.1.1 <br />01-23 602 S Genoa Dr 1-Story_R3.xls, Seismic Analysis-2018 IBC <br />Page 6