Steel Structures by Vinnakota
Chapter 3
page 3-1
CHAPTER 3 P3.1.
What is the difference difference between between braced braced and unbraced frames? Illustrate with the help help of single span, twostory frame. Solution
In braced frames subjected to horizontal and vertical loads, the joints rotate but remain essentially in place. Thus there is no relative translation of the ends ends of a column when a braced braced frame is subjected to lateral loads. In unbraced frames subjected to horizontal and vertical loads, the joints are free to translate horizontally in addition to rotation. Thus, columns in braced frames are subjected to chord deflections, δ, only; while columns in unbraced frames are subjected to both sway deflections, Δ, and chord deflections, δ. P3.2.
In a tier building, W16x36 floor beams are 30 ft long and spaced at 6 ft intervals, while the W21x62 girders are 24 ft long. The girders are connected connected to the flange flange of W12x65 columns. columns. Show the floor framing layout for an interior bay.
W21x62 Girder W12x65 Column
30 ft
W16x36 Floor beam
4 @ 6 ft = 24 ft
Figure SP3.2:
Floor framing layout for an interior bay
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Chapter 3 P3.3.
page 3-2
Illustrate any two types of shear bents in tier buildings. Solution
See Figure 3.3.6 of the text book.
P3.4.
Sketch any three types of concentrically braced shear bents, for a four story building. Solution
See Figure 3.3.7 of the text book.
P3.5.
What are purlins and sag rods. Solution Purlins Horizontal, longitudinal, structural members that rest on the top chords of roof trusses or girders to support the roof deck. Sag rods Steel threaded rods that are used to provide intermediate support for roof purlins or wall girts in their weak plane.
PROPRIETARY MATERIAL. © 2006 The McGraw-Hill Companies, Inc. All rights reserved. No part of this Manual may be displayed, reproduced or distributed in any form or by any means, without the prior written permission of the publisher, or used beyond the limited distribution to teachers and educators permitted by McGraw-Hill for their individual course preparation. If you are a student using this Manual, you are using it without permission.
