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"ASCE7-16W.xls" Program Version 2.1 <br />Determination of Gust Effect Factor, G: <br />Is Building Flexible?No f >=1 Hz. <br />1: Simplified Method for Rigid Building <br />G =0.850 <br /> Parameters Used in Both Item #2 and Item #3 Calculations (from Table 26.9-1): <br />a^ =0.105 <br />b^ =1.00 <br />a(bar) =0.154 <br />b(bar) =0.65 <br />c =0.20 <br />l =500 ft. <br />e(bar) =0.200 <br />z(min) =15 ft. <br /> Calculated Parameters Used in Both Rigid and/or Flexible Building Calculations: <br />z(bar) =15.00 = 0.6*h , but not < z(min) , ft. Table 26.9-1 <br />Iz(bar) =0.228 = c*(33/z(bar))^(1/6) , Eq. 26.9-7 <br />Lz(bar) =427.06 = l*(z(bar)/33)^(e(bar)) , Eq. 26.9-9 <br />gq =3.4 (3.4, per Sect. 26.9.4) <br />gv =3.4 (3.4, per Sect. 26.9.4) <br />gr =4.535 = (2*(LN(3600*f)))^(1/2)+0.577/(2*LN(3600*f))^(1/2) , Eq. 26.9-11 <br />Q =0.920 = (1/(1+0.63*((B+h)/Lz(bar))^0.63))^(1/2) , Eq. 26.9-8 <br />2: Calculation of G for Rigid Building <br />G =0.883 = 0.925*((1+1.7*gq*Iz(bar)*Q)/(1+1.7*gv*Iz(bar))) , Eq. 26.9-6 <br />3: Calculation of Gf for Flexible Building <br />b =0.050 Damping Ratio <br />Ct =0.035 Period Coefficient <br />T =0.221 = Ct*h^(3/4) , sec. (Approximate fundamental period) <br />f =4.531 = 1/T , Hz. (Natural Frequency) <br />V(fps) =N.A.= V(mph)*(88/60) , ft./sec. <br />V(bar,zbar) =N.A.= b(bar)*(z(bar)/33)^(a(bar))*V*(88/60) , ft./sec. , Eq. 26.9-16 <br />N1 =N.A.= f*Lz(bar)/(V(bar,zbar)) , Eq. 26.9-14 <br />Rn =N.A.= 7.47*N1/(1+10.3*N1)^(5/3) , Eq. 26.9-13 <br />hh =N.A.= 4.6*f*h/(V(bar,zbar)) <br />Rh =N.A.= (1/hh)-1/(2*hh^2)*(1-e^(-2*hh)) for hh>0, or = 1 for hh=0 ,Eq. 26.9-15a, b <br />hb =N.A.= 4.6*f*B/(V(bar,zbar)) <br />RB =N.A.= (1/hb)-1/(2*hb^2)*(1-e^(-2*hb)) for hb>0, or = 1 for hb=0,Eq. 26.9-15a, b <br />hd =N.A.= 15.4*f*L/(V(bar,zbar)) <br />RL =N.A.= (1/hd)-1/(2*hd^2)*(1-e^(-2*hd)) for hd>0, or = 1 for hd=0 ,Eq. 26.9-15a, b <br />R =N.A.= ((1/b)*Rn*Rh*RB*(0.53+0.47*RL))^(1/2) , Eq. 26.9-12 <br />Gf =N.A.= 0.925*(1+1.7*Iz(bar)*(gq^2*Q^2+gr^2*R^2)^(1/2))/(1+1.7*gv*Iz(bar)) , <br />Use: G =0.850 Eq. 26.9-10 <br />3 of 4 4/4/2025 11:50 AM