Docsity
Docsity

Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity


Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan


Guidelines and tips
Guidelines and tips

Steel Design Problem Sets (Complete – Chapters 1 to 6), Exercises of Civil Engineering

✅ Chapter 1 – Introduction Basic steel design problems, load types, and code-based classifications ✅ Chapter 2 – Tension Members Problems on net area, tensile strength, rupture/yielding checks ✅ Chapter 3 – Compression Members Buckling analysis, slenderness ratio (KL/r), critical load computations ✅ Chapter 4 – Beams Bending stress, shear capacity, and lateral-torsional buckling problems ✅ Chapter 5 – Beam-Columns Combined axial and bending load problems, interaction checks ✅ Chapter 6 – Connections Design problems for bolted and welded connections, strength checks

Typology: Exercises

2023/2024

Available from 06/05/2025

imwinter
imwinter 🇵🇭

5

(1)

148 documents

1 / 35

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
Chapter 01 – Introduction and Properties of Sections
PROBLEM 01
Locate the centroid of the shaded area.
Solution
A
1
=8
(
4
)
=32 m
2
x1=0
y1=2m
A2=2
(
2
)
=4m2
x
2
=−2m
y
2
=3m
A
3
=1
2π(1)
2
=0.5 π m
2
y
3
=44
(
1
)
3π=3.576 m
[AT=A1+A2+A3]
AT=3240.5 π
A
T
=26.429 m
2
[ATYG=Ay]
26.429 Y
G
=32
(
2
)
4
(
3
)
0.5 π(3.576)
YG=1.755 m
[A
T
X
G
=
Ax]
26.429 Y
G
=32
(
0
)
4
(
2
)
0.5 π(2)
YG=0.18 m
pf3
pf4
pf5
pf8
pf9
pfa
pfd
pfe
pff
pf12
pf13
pf14
pf15
pf16
pf17
pf18
pf19
pf1a
pf1b
pf1c
pf1d
pf1e
pf1f
pf20
pf21
pf22
pf23

Partial preview of the text

Download Steel Design Problem Sets (Complete – Chapters 1 to 6) and more Exercises Civil Engineering in PDF only on Docsity!

Chapter 01 – Introduction and Properties of Sections

PROBLEM 01

Locate the centroid of the shaded area.

Solution

A

1

= 32 m

2

x

1

= 0 y

1

= 2 m

A

2

= 4 m

2

x

2

=− 2 m y

2

= 3 m

A

3

π ( 1 )

2

=0.5 π m

2

x

3

= 2 m y

3

3 π

=3.576 m

[ A

T

= A

1

+ A

2

+ A

3

] A

T

= 32 − 4 −0.5 π

A

T

=26.429 m

2

[ A

T

Y

G

Ay ] 26.429 Y

G

= 32 ( 2 )− 4 ( 3 ) −0.5 π ( 3.576)

Y

G

=1.755 m

[ A

T

X

G

Ax ]

26.429 Y

G

= 32 ( 0 ) − 4 (− 2 )−0.5 π ( 2 )

Y

G

=0.18 m

PROBLEM 02

With reference to the plane area, determine the following:

a.) The area of the plane in square millimeters.

b.) The x-coordinate of the centroid.

c.) The y-coordinate of the centroid.

Solution

A

1

x

1

= 20 ; y

1

A

2

x

2

= 55 ; y

1

A

3

x

3

; y

3

A

4

x

4

; y

3

A

T

A = 7800 m

2

[ A

T

´ x =

ax ]

Y-Axis:

I

X

3

3

I

X

=8,797,500 mm

4

[ S

Y

I

Y

c

]
S

Y

S

Y

=117,300 mm

3

[ r

y

I

y

A

T

]

r

x

r

x

=30.76 mm

Chapter 02 – Bolted and Riveted Connections and

Tension Members

PROBLEM 01

The single 200 mm x 10 mm steel plate is connected to a 12-mm thick steel plate by four 16 mm diameter

rivets. The rivets used are A502, Grade 2, hot driven rivets. The steel ASTM A36 with F y

= 248 MPa and

F u

= 400MPa. Determine the value of P in all possible modes of failure and the safe value of P that the

connection can resist.

Solution:

Riveted Diameter = 16 mm

Hole = 16 = 1.6 = 17.6 mm

Tension on gross area:

F

t

=0.6 F

y

=0.6 ( 248 )=148.8 MPa

A

g

= 2000 mm

2

P = F

t

A

g

P = 297600 N =297.6 kN

Tension on net area:

F

t

=0.5 F

u

=0.5 ( 400 )= 200 MPa

Tension on net area Tension on gross area

Net area along section a-a :

A

e

= 200 − 2 ( 17.6)
A

e

= 1648 mm

2

85 % A

g

85 % A

g

= 1700 mm

2

P = F

t

A

e

P = 329000 N =329.6 kN

Bearing on projected area:

F

p

=1.2 F

u

=1.2 ( 400 )= 480 MPa

A

p

dt =[ 16

]

= 640 mm

2

P = F

p

A

p

P = 307200 N =307.2 kN

Shear on rivets

F

v

= 152 MPa

A

v

π

P = F

v

A

v

P = 122246 N =122.246 kN

Shear rapture (block shear):

P = F

v

A

v

+ F

t

A

t

F

v

=0.3 F

u

F

v

= 120 MPa

A

v

= 2 A

bc

[

]

A

v

= 2172 mm

2

F

t

=0.5 F

u

F

t

= 200 MPa

A

t

A

ab

[

]

A

t

= 824 mm

2

A

n

A

n

=1835.2 mm

2

Use A

n

= 1700 mm

2

A '

n

= A

g

= 1700 mm

2

Along second row:

A

n

[

]

A

n

=1670.4 mm

2

A '

n

A

n

n

N
A '

n

A '

n

=1879.2 mm

2

Along third row:

A

n

[

]

A

n

=1505.6 mm

2

A '

n

A

n

n

N
A '

n

A '

n

=1879.2 mm

2

Use A '

n

= 1700 mm

2

(governed by tearing along the first row)

P = F

t

A '

u

P = 200 ( 1700 ) = 340000 N

P = 340 kN

The safe load P =297.6 kN , governed by tension on gross area.

PROBLEM 03

A plate with a width of 400 mm and thickness of 12 mm is to be cconnected to a plate of the same width

and thickness by 34 mm diameter bolts, as shown. The holes are 2 mm larger than the bolt diameter. The

plate is A36 stel with yield strength F y

= 248 MPa. Assume allowable tensile stress on the net area is

0.60F y

. It is required to determine the value of b such that the net width along bolts 1-2-3-4 is equal to the

net width along bolts 1-2-4.

a) Calculate the value of b in millimeters.

b) Calculate the value of the net area for tension in plates in square millimeters.

c) Calculate the value of P so that the allowable tensile stress on the net area will no be

exceeded.

Solution

Any critical path of the top plate shown above, the load is 100% of P , hence no reduction of net area is

required. For the bottom plate, for path 1-2-3, only 75% of P acts on the net area, while for path 1-2-3-4,

100% of P acts on the net area.

Part a:

Net width = Gross width

holes +

s

2

4 g

Net width (1-2-4) = Net width (1-2-3-4)

2

( 150 − b )

2

2

b

2

2

( 150 − b )

2

b

2

22500 − 300 b + b

2

− 2 b

2

b

2

  • 300 b − 6300 = 0

b =

2

b =19.71 mm

Solution

Since there are two identical plates, let us analyze one plate only using half of the given load,

P = 1000/2 = 500 kN

Direct load:

R

D

P
N

=62.5 kN

Load due to moment:

R

x

T

y

( x

2

  • y

2

R

y

T

x

( x

2

  • y

2

T = Pe = 500

= 145 kN ∙ m

2

( x

2

  • y

2

2

2

2

2

) = 128800 mm

2

Note: The farther the fastener is from the cg, the greater is load due to moment

Considering bolt 1: ( x = 90 , y = 120 ¿

R

1 Tx

145 × 10

6

= 135093 N
R

1 Ty

145 × 10

6

= 101320 N
R

1 x

= R

1 Tx

= 135093 N
R

1 y

= R

1 Ty

+ R

D

= 101320 + 62500 = 163820 N
R

1

R

1 Tx

2

+ R

1 y

2

R

1

2

2

R

1

= 212337 N =212.34 kN

PROBLEM 02

The gusset is riveted to a larger plate by four 22-mm rivets in single shear arranged and loaded as shown.

Calculate the stress in the most heavily loaded rivet.

Solution

The gusset shown is riveted to the column flange by 7 20-mm diameter rivet in single shear. Determine

the stress in the most-heavily loaded bolt.

Solution

Direct load:

R

D

= 20 kN

Moment:

Centroid

n × X

G

x

7 X

G

X

G

=114.29 mm

n ×Y

G

y

7 Y

G

Y

G

=257.14 mm

e = 200 + 175 − X

G

e =260.71 mm

T = 140 e = 140 (0.26071)

T =36.5 kN ∙ m

( x

2

  • y

2

2

2

2

2

2

2

( x

2

  • y

2

R

T 4 x

T

y 4

( x

2

  • y

2

R

T 4 x

36.5 × 10

6

=39817.7 N
R

T 4 x

=39.818 kN

R

T 4 y

T

x 4

( x

2

  • y

2

R

T 4 y

36.5 × 10

6

= 13272 N
R

T 4 y

=13.272 kN

R

4

( R ¿¿ T 4 x )

2

+( R
¿ D + R

T 4 y

2

R

4

2

2

R

4

=51.89 kN

f

v max

π ( 20 )

2

=165.17 MPa

Effective area = 700

= 5197 m

2

c) Considering the upper weld only:

P = F

v

A

v

F

v

=0.3 F

u

F

v

= 330 MPa

A

v

=0.707 tL

A

v

A

v

= 2598 mm

2

P = 330 ( 2598 )

P = 857414 N =857.4 kN

PROBLEM 02

A double-angle truss member shown consist of two angles 125 mm x 88 mm x 10 mm thick with the 125

mm side welded to a gusset plate. The member is to carry a total tensile force of 848 kN. Using 6-mm

fillet weld with E60 electrode, determine the length of each side fillet weld required for balanced

condition. All steels are A36 with F y

= 250 MPa

Solution

F

u

= 425 MPa for E60 electrode

Allowable shear on effective area of weld

F

v

=0.3 F

u

=0.3 ( 425 ) =127.5 MPa

Allowable shear on base metal

F

v

=0.4 F

y

=0.4 ( 250 )= 100 MPa

Considering one member only:

P =

= 424 kN

Length of weld on one side , L = L

1

+ L

2

Based on weld metal shear:

P =0.707 tL F

v

424000 =0.707 ( 6 ) ( L ) (127.5 )

L = 784 mm

Based on base metal shear:

A

v

= t × L = 6 L (contact area between the weld and metal)

P = A

v

F

v

424000 = 6 L ( 100 )

L = 706 mm

Use L = 784 mm

For balanced condition:

L

1

y

1

= L

2

y

2

L

1

( 40 )= L

2

L

1

=2.125 L

2

L = L

1

+ L

2

2.125 L

2

+ L

2

L

2

=250.88 mm

L

1

=533.12 mm

PROBLEM 03

A plate is lapped over and welded to a gusset plate as shown.

a) Determine the maximum force per millimeter of weld due to moment alone acting at the

centroid of the weld group

b) Determine the maximum force per millimeter of weld due to the given load

Solution

Direct Load:

R

D

P
L

Chapter 04 – Columns and Other Compression

Members

PROBLEM 01

Two A36 L150 x 90 x 10 angles are used with a 10-mm gusset plate to create a top chord of a truss. The

long legs are back-to-back making the short legs unstiffened elements. Determine the axial load capacity

for a length of 2 meters.

SOLUTION

Properties of one L150 x 90 x 10:

Area = 2,315 mm

2

t = 10 mm

I x

= 5,331,434 mm

4

I y

= 1,460,745 mm

4

´ x =20.

´ y =49.

Properties of 2L 150 x 90 x 10

With long legs back-to-back

A` = 2A = 4,630 mm

4

I` x

= 2I x

= 10,662,868 mm

4

r

x

I x

A

I` y

= 2 x [ I y

  • Ax

2

]

I` y

= 2 x [1,460,745 + 2,315(20.36 + 5)

2

I` y

= 5,899,190 mm

4

r

y

I y

A

=35.69= r

min

Check local buckling. The 90-mm legs of this double angle member are unstiffened compression

elements

b = 90, t = 10 mm

b/t = 9

H= 200

H

F

y

Since ¿ t < H /

F

y

, the combination can fully develop compressive stress.

C

r

2 π

2

KL

r

=56.04 < C

r

Since

KL

r

< C

r

FS =

3 ( KL / r )

8 C

c

( KL / r )

3

8 C

c

3

FS =

3

3

F

a

(

( KL / r )

2

2 C

c

2

)

F

y

FS
F

a

(

2

2

)

(

)

F

a

=122.7 MPa

[P = F a

A] P = 122.7(4,630)

P = 568,101N = 568.101 kN

PROBLEM 02

A double angle compression chord member for a truss consist of 2 L200 x 100 x 12, having a short legs

back-to-back in a 10-gusset plate. The member is braced in the plane of the truss every 2.13 m, but only at

the end of the transverse and the spacing of connectors is close enough that the double angle member

reaches its maximum axial load strength. Use A