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Faculty of Engineering Civil Engineering DepartmentFirst Course 2015-2016 Reinforced Concrete (2) Second ExaminationTime: 50 Minutes Date: 10/1/2016Lecturer: Dr. Saad Ali Al-Taan Page Student Number:

Question 3: (8 Marks)A rectangular reinforced concrete column in a sway (unbraced) frame with b = 300 mm, h = 450 mm, k = 1.15, and Lu

column.SOLUTIONk.Ɩu/r = 1.15×3.75/(0.3×0.45) = 31.94 > 22 (therefore it is long column)

Question 4: (42 Marks)A rectangular reinforced concrete column in a nonsway (braced) frame with b = 300 mm, h = 400 mm, k = 0.9, and LMN and a factored moments at the two ends Mis bent in single curvature. i. Check whether the column is short or long (slender) column. ii. Calculate the moment correction factor Ciii. Calculate EI for the column. iv. Calculate the critical buckling load Pv. Calculate the moment magnification factor vi. What is the factored load and moment that should be considered in design

SOLUTIONi. k.Ɩu/r = 0.9×3.6/(0.334 -12(M1/M2) = 34 -12 (60/75) = 24.4 ((therefore it is long column)

ii. ii. Cm = 0.6 +0.4(M1/M2) = 0.6+0.4(60/75) = 0.92iii. EC = 4730 √30 = 25907 MPa,

I = 0.3(0.4)3/12 = 0.0016 mE.I = 0.4Ec .Ig/(1+

iv. Pc = π2.EI/(k.Ɩu)2 = v. δns = Cm / [1-Pul(0.75Pvi. Min. M = 1.5(15+0.03 Mc = 1.139×75 = 85.44 kN.m and P