4.8.4. Amplification of Reduced Internal Forces and Displacements According to Equivalent Base Shear Force

4.8.4.1 - In case V tx (X) <E * V tE (X) for any earthquake direction (X) , all reduced internal force obtained by the modal calculation method applied according to 4.8.2 or 4.8.3 and The displacement magnitudes will be enlarged by multiplying the equivalent base shear amplification coefficient β tE (X) given by Eq (4.31) .

Wherein V t (X) to the lateral force Method according to Eq. (4.21) calculated by the total equivalent seismic load (base shear force), V tx (X) is 4.8.2 or 4.8.3 according x direction 'in It shows the total earthquake load obtained . γ The factor of E will be taken as follows:

(a) If at least one of the A1 , B2 or B3 type irregularities defined in Table 3.6 is present in the building, γ E = 0.90 shall be taken.

(b) If none of the irregularities defined in Table 3.6 are present in the building, γ E = 0.80 shall be taken.

According to the definition given in 4.8.4.2 - 3.3.1 , in buildings with externally rigid walls surrounded by basements, the equivalent base shear force amplification coefficient shall be calculated only for the upper part above the basement floors of the building .