M.S. Comprehensive Examination: Design

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1 UNIVERSITY OF CALIFORNIA, BERKELEY Dept. of Civil and Environmental Engineering Spring Semester 2017 M.S. Comprehensive Examination: Design Consider the shown frame and the cross-section of the column in the figure below. Consider onl one option for the column: steel or reinforced concrete. Calculate the factored load P that can be applied to this structure. Distributed factored load is 20 kip/ft. Check all bending and shear failure modes and indicate whether or not the column is adequate to carr the loads. The steel column is sufficientl braced and lateral-torsional buckling is not a consideration. The beam does not need to be designed and can be assumed to have sufficient strength. All the information ou need for this problem is given below, still, if ou feel ou need a piece of information that is not given, make a reasonable assumption and continue the problem. You can use approximate equations if ou do not remember the exact equation, but, ou have to explain the approximation and how that approximation might affect our answer. P 20 kip/ft 5 ft 20 ft z STEEL CONCRETE

2 UNIVERSITY OF CALIFORNIA, BERKELEY Dept. of Civil and Environmental Engineering Spring Semester 2017 Ph.D. Preliminar Examination: Design Consider the frame shown below subjected to dead load and earthquake loading. Ignore the selfweight and select our material (steel or reinforced concrete) as ou prefer making use of the information given below. All loads are unfactored. Use factored load combinations in our design. According to our chosen material, design the column either as a R/C column or a steel column. For the concrete case use a reinforced concrete square section. For the steel case, use a box section. The beam design is not part of this problem. You do not need to consider buckling in the column design. Justif an assumptions ou ma make. After designing the column, compute the horizontal deflection at the column under the given unfactored (service) forces assume linear elastic response in our calculation. The horizontal deflection should be limited to 1/1000 of the column height because of the presence of important drift-sensitive nonstructural components. If the calculated deflection is larger than this limit, comment (without calculations) on how the deflection can be reduced. 30 kip/ft (Dead load) 20 kip (Earthquake Load) 5 ft 20 ft STEEL Steel: F=36 ksi, Fu=58 ksi CONCRETE Steel rebars: F=60 ksi; Concrete: f c=4,000 psi

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4 Student s Name (Please Print) (Last: ) (First: ) Universit of California, Berkele Department of Civil and Environmental Engineering Comprehensive Examinations- Spring 2015 DESIGN Question Consider onl one of the two 6-stor frames shown below. The frame is subjected to lateral loads due to earthquakes as shown and gravit loads. Foundation design is not part of this problem. The loads shown are factored loads. You need to make assumption on an information or equations that ou need to do this problem and are not given on this sheet. You will be graded based on validit of our assumptions. If ou considered the R/C frame, then check the compression column on the right side and establish how much factored gravit load the column can take. The cross section of R/C column is given below. If ou considered the STEEL frame, then check the compression column on the right side and establish how much factored gravit load the column can take. The cross section of the steel column is a W12x120 with following properties given in the attached table from the AISC Manual. The steel for the column is A913 Gr 65 with F= 65 ksi. Notice that ou onl need to consider steel OR reinforced concrete frame not both. 40 kips 25 kips 25 ft 48 kips 35 kips 25 ft 20 kips 15 kips 10 kips 5 kips Ground Floor 28 kips 21 kips 14 kips 7 kips Ground Floor W12x120 A913 Gr. 65 (F=65 ksi) Steel Column Section #4 10 c/c Concrete 18 x18 f c =6,000 psi, w =150 lb / ft 3 8 #10 rebars (dia=1.25 in.) F = 60 ksi x R/C Column Section x STEEL OR REINF. CONC.

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