Structures with Basement (184.108.40.206)
In buildings with basements surrounded by rigid bulkheads as required by 220.127.116.11 , (R / I) = 2.5 and D = 1.5 are taken automatically for the lower section.
D = Strength Redundancy Coefficient
I = Building Priority Coefficient
R = Structural System Behavior Coefficient
As shown in the example below, in buildings with basements surrounded by rigid walls from the outside, (R / I) = 2.5 and D = 1.5 in the sub-sections with basement floors.
Modal Response Spectrum Analysis of Structures with Basement Internal Design Force of Elements of Building with Basement