Solutions Manual for Structural Steel Design (3rd Edition by Aghayere) – Complete Problem Solutions

All13 Chapters Covered
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SOLUTIONS

, Contents
Chapter 1............................................................................................................................................ 1
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Chapter 2............................................................................................................................................ 6
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Chapter 3............................................................................................................................................ 23
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Chapter 4............................................................................................................................................ 41
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Chapter 5............................................................................................................................................ 55
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Chapter 6............................................................................................................................................ 62
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Chapter 7............................................................................................................................................ 74
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Chapter 8............................................................................................................................................ 84
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Chapter 9............................................................................................................................................ 92
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Chapter 10...........................................................................................................................................109
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Chapter 11...........................................................................................................................................119
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Chapter 12...........................................................................................................................................137
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Chapter 13...........................................................................................................................................154
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Appendix B ......................................................................................................................................... 159
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,Problem 1-4 o




The size and cross-sectional areas are obtained from Part 1 of the AISCM as follows:
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Size Self-weight (lb/ft.) o Cross-sectional area (in2) o o




W14x22 22 6.49
W21x44 44 13.0
HSS 6x6x½ o 35.11 9.74
L6x4x½ 16.2 4.75
C12x30 30 8.81
WT18x128 128 37.7


Problem 1-5 o




a)

Element A y Ay I d = y-y
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I + Ad2
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top flange o 21 26.25 551.25 3.94 -12.75 3418
web 21 13.5 283.5 1008 0 1008
bot flange o 21 0.75 15.75 3.94 12.75 3418
= o 63 in.2 o 850.5 I = 7844 in.4
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Ay 850.5
y= = = 13.5 in.
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A 63
Self weight = (63/144)(490 lb/ft3) = 214 lb/ft.
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b)

Element A y Ay I d = y-y
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I + Ad2
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top plate o 2.63 18.26 47.93 0.03 -9.04 214.3
beam 10.3 9.23 95.02 510 0 510
bot plate o 2.63 0.188 0.49 0.03 9.04 214.3
= o 15.55 in.2 o 143.4 I = 939 in.4
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Ay 143.4
y= = = 9.23 in.
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A 15.55
Self weight = (15.55/144)(490 lb/ft3) = 52.9 lb/ft.
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c) From AISCM Table 1-20, Ix = 314 in.4
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Area = 13.8 in2 o o o




Self weight = 47.1 lb/ft. o o o o




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, Problem 1-7 o




Plot the idealized stress-strain diagram for a 6-in. wide by ½-in. thick plate and a 6-in. wide by 1-in. thick plate
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of ASTM A36 steel. Assume that the original length between two points on the specimen over which the
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elongation will be measured (i.e. the gage length) is 2-in.
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Solution:

Gage length, Lo = 2 in. o o o o o




For 6 x ½-in. plate, Area = (6 in.)(½ in.) = 3 in2 E =
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29,000 ksi
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P Stress = P/A o o Strain,  = P/EA o o o Elongation, Lo = Strain x gage length = Lo
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(kips) (ksi) (in.)
0 0 0 0
20 6.67 0.00023 0.00046
40 13.33 0.00046 0.00092
60 20.0 0.00069 0.00138
80 26.67 0.00092 0.00184
100 33.33 0.00111 0.00222
108 36.0 0.00124 0.00248



For 6 x 1-in. plate, Area = (6 in.)(1 in.) = 6 in2
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P Stress = P/A o o Strain,  = P/EA o o o Elongation, Lo = Strain x gage length = Lo
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(kips) (ksi) (in.)
0 0 0 0
40 6.67 0.00023 0.00046
80 13.33 0.00046 0.00092
120 20.0 0.00069 0.00138
160 26.67 0.00092 0.00184
200 33.33 0.00111 0.00222
216 36.0 0.00124 0.00248


Problem 1-8 o




Determine the most economical layout of the roof framing (joists and girders) and the gage
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(thickness) of the roof deck for a building with a 25 ft x 35 ft typical bay size. The total roof dead load is
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o25 psf and the snow load is 35 psf. Assume a 1½” deep galvanized wide rib deck and an estimated
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weight of roof framing of 6 psf.
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*Assume beams (or joists) span the 35’ direction
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* Assume 3-span condition o o




*Total roof load = (25psf + 35psf) – 6psf = 54psf
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