SAUDI BUILDING CODES

Par. 10.9.3 of SBC 301 provides 3 methods of calculating this size. Specific conditions must be met in order to apply each method. The program options are as follows: ▪ Unfavourable ▪ Average ▪ Method 1 ▪ Method 2 ▪ Method 3 The first option takes as the final value of the fundamental eigenperiod of the structure the worst value obtained after the calculation based on each method separately. The second option selects the average of the three values and subsequent options select the specific value from that method. In each case two values are calculated, one for each direction of the earthquake. The next option is for the building type based on Table 10.9.3.2 and concerns the calculation with the first method (Eq. 10.9.3.2-1). The next section concerns the determination of the lower and upper levels where the seismic load will be applied. The following parameters are related to the dynamic analysis. More specifically in the following fields: you specify the number of eigenmodes you want to take into account when performing the eigenmodal analysis as well as the accuracy factor of the calculations. Then you can determine seismic force participation factors per seismic direction Check the corresponding checkbox and enter the seismic load factor. The default option is 1, and if for example you set PFx=2 the values of the spectrum in the X direction will be doubled. Similarly, in order to modify the coefficients for the calculation of the eccentricities