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Q22. A one-story reinforced-concrete building is idealized for structural analysis as a massless frame supporting a dead load of 10 kips at the beam level. The frame is 24 ft wide and 12 ft high. Each column, clamped at the base, has a 10-in.-square cross section. The Young's modulus E of concrete is E-3 x 10' ksi, and the damping ratio of the building is estimated as 5%. If the building is to be designed for the design spectrum of Figure shown below scaled to a peak ground acceleration of 0.5g. determine the design values of lateral deformation and bending moments in the columns for two conditions: (a) The cross section of the beam is much larger than that of the columns, so the beam may be assumed as rigid in flexure. (b) The beam cross section is much smaller than the columns, so the beam stiffness can be ignored. Comment on the influence of beam stiffness on the design quantities. Elastic pseudo-acceleration design spectrum • Ugo = 19, 40 = 48 in./sec, and ugo= 36 in. (= 5% 5 2.71 Pseudo-acceleration A, g 0.1 .01 0.02 11.707,0.704 12' 1/33 sec- 1/8 sec 0.66 sec 4.12 sec 10 sec 0.1 1.8071 imm TẠO Tỏ 2014 T 1 Natural vibration period T sec 24' 77777 H 10