Behavior and Strength of Cold-Formed Steel Lipped Channel Section with Track under Compression

1. BEHAVIOR AND STRENGTH WATANAPONG
OF COLD-FORMED STEEL HIRANMARN
PRAKIT PREMTHAMAKORN
LIPPED CHANNEL SECTION PRAKIT CHOMCHUEN
NUTHAPORN
WITH TRACK UNDER NUTTAYASAKUL
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND
COMPRESSION

2. OUTLINE
 INTRODUCTION
 Load-Bearing Wall System
 OBJECTIVE
 SCOPE
 EXPERIMENTAL INVESTIGATION
 FINITE ELEMENT ANALYSIS
 CONCLUSION
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

3. INTRODUCTION
 Load-Bearing Wall System
s
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

4. OBJECTIVE
 The main objective is to present the compressive
behavior of stud-track from experimental investigation
and Finite Element Analysis (FEA)
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

5. SCOPE
 Compression tests were conducted on 19 specimens for
300mm and 800mm length cold-formed steel C-section
columns with stud and stud-track
 Finite Element Analysis (FEA) was conducted for 300mm
length
stud specimens
 The Ultimate experimental compressive strengths of the
studs are compared with the design strengths calculated
(AISI 2007)
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

6. EXPERIMENTAL
INVESTIGATION
o Test Specimens
(a) Stud Specimens
(b) Stud-Track
Specimens
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

7. EXPERIMENTAL
INVESTIGATION
o Section Dimensions
B
H
H
D
B
t
t
r
•Stud:
100x50x20x1.6mm
•tact,aver = 1.43mm
r
•Track: 105x50x1.6mm
•tact,aver = 1.53mm
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

8. EXPERIMENTAL
INVESTIGATION
o Material Properties (JIS Z 2241-1998)
Coupon
fy (MPa)
fu (MPa)
E (MPa)
Elogation (%)
Stud
292.25
358.68
218,385
40.6
Track
280.64
345.82
190,426
39.4
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

9. EXPERIMENTAL
INVESTIGATION
o Initial Geometric Imperfection
fr
A
w
fl
B
2
C
Imperfaction ( mm. )
1.5
1
A
0.5
B_Left
0
-0.5 0
50
100
150
200
250
-1
300
B_Mid
B_Right
C
-1.5
-2
Length ( mm. )

w ,m ax
 1 . 775 m m

f ,m ax
 1 . 217 m m
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

10. EXPERIMENTAL
INVESTIGATION
o Test Rig and Gauge Arrangement
Ten transducers were installed to record the displacements of the specimen under the
progressive increase in the axial compression, one for vertical and night for horizontal direction
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

11. EXPERIMENTAL
INVESTIGATION
o Stud Test Results ( L= 300mm)
70
Max.
65
Specimen
Pu
(kN)
Failure
modes
60
55
31.8% of
max.
Min.
50
C300-1
C300-2
C300-3
C300-4
C300-5
C300-6
Average
62.98
61.70
44.46
62.05
49.93
42.96
54.01
L
L
L
L
L
L
Load ( kN. )
45
40
35
30
25
20
15
10
5
0
0
1
2
3
4
5
6
7
8
9
10
11
12
Displacement ( mm. )
Local
buckling
C300-1 (Pu=62.98)
C300-2 (Pu=61.70)
C300-3 (Pu=44.46)
C300-4 (Pu=62.05)
C300-5 (Pu=49.93)
C300-6 (Pu=42.96)
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

12. Load ( Ton. )
EXPERIMENTAL
INVESTIGATION
o Stud Test Results ( Typical failure of C300-2)
7
6.5
6
5.5
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
0
0
1
2
3
4
5
6
7
8
Displacement ( mm. )
9
10
11
12
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

13. EXPERIMENTAL
INVESTIGATION
o Stud Test Results ( Typical failure of C300-2)
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

14. Load ( Ton. )
EXPERIMENTAL
INVESTIGATION
o Stud Test Results ( C300-3 specimen)
7
6.5
6
5.5
5
4.5
4
3.5
3
2.5
2
1.5
1
0.5
0
0
1
2
3
Displacement ( mm. )
4
5
6
7
8
9
10
11
12
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

15. EXPERIMENTAL
INVESTIGATION
o Stud Test Results ( C300-3 specimen)
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

16. EXPERIMENTAL
INVESTIGATION
o Stud Test Results ( L= 800mm)
70
65
Specimen
Pu
(kN)
Failure
modes
60
55
50
C800-1
C800-2
C800-3
Average
52.40
52.44
47.43
50.76
L
L
L
Load ( kN )
45
40
35
30
25
20
15
10
5
0
Local
buckling
Average C300
54.01
Less than
C300
0
1
2
3
4
5
6
7
8
9
10
11
12
Displacement ( mm. )
C800-1 (Pu=52.40)
C800-2 (Pu=52.44)
C800-3 (Pu=47.43)
about 6%
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

17. EXPERIMENTAL
INVESTIGATION all C800 specimens)
o Stud Test Results (Final failure shape of
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

18. EXPERIMENTAL
INVESTIGATION
o Stud-Track Test Results ( L=
300mm)
Specimen
Pu
(kN)
70
65
Failure
modes
60
55
50
45
66.68
65.46
60.36
58.70
69.19
66.68
66.86
64.85
L
L
L
L+D
L
L
L
40
Load ( kN. )
CT300-1
CT300-2
CT300-3
CT300-4
CT300-5
CT300-6
CT300-7
Average
35
30
25
20
15
10
5
0
0
1
2
3
4
5
6
7
8
9
10
11
Displacement ( mm. )
54.01
CT300-1 (Pu=66.68)
More than
C300
about 20%
CT300-2 (Pu=65.46)
CT300-3 (Pu=60.36)
CT300-4 (Pu=58.70)
Average C300
12
CT300-5 (Pu=69.19)
CT300-6 (Pu=66.68)
CT300-7 (Pu=66.86)
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

19. EXPERIMENTAL
INVESTIGATION
o Stud-Track Test Results (Typical final failure shape of CT300-6 and -7)
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

20. EXPERIMENTAL
INVESTIGATION
o Stud-Track Test Results ( L=
800mm)
70
65
60
Specimen
Pu
(kN)
Failure
modes
55
50
45
CT800-1
CT800-2
CT800-3
Average
62.23
63.18
67.92
64.44
L
L
L
Load ( kN. )
40
35
30
25
20
15
10
5
0
0
Local
buckling
Average C800
50.76
More than
C800
about 27%
1
2
3
4
5
6
7
8
9
10
11
12
Displacement ( mm. )
CT300-1 (Pu=66.68)
CT300-2 (Pu=65.46)
CT300-3 (Pu=60.36)
CT300-4 (Pu=58.70)
CT300-5 (Pu=69.19)
CT300-6 (Pu=66.68)
CT300-7 (Pu=66.86)
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

21. EXPERIMENTAL
INVESTIGATION
o Stud-Track Test Results (Final failure shape of all CT800)
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

22. FINITE ELEMENT ANALYSIS
o Finite Element Model of Stud 300mm
ABAQUS/CAE
•Stud :
v. 6.11Shell
450
400
Stress (N/sqr.mm)
•Stud : Mesh size
Element (S4R)
•Plate :
5x5 mm
Analytical rigid
•Friction Coef.
= 0.3Top Pl. move down
•BC :
only: Bottom Pl
•BC
is fixed.
•Non-Linear Static
Analysis, General
•Inclined section
imperfection
•Local
imperfection
350
300
250
200
150
100
50
0
0
0.02
0.04
0.06
Strain (mm/mm)
0.08
0.1
True_Plastic
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

23. FINITE ELEMENT ANALYSIS
o Finite Element Model of Stud C300-4
Section imperfection (Inclined section)
2-Planes
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

24. FINITE ELEMENT ANALYSIS
o Finite Element Model of Stud C300-4
Section imperfection (Inclined section)
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

25. FINITE ELEMENT ANALYSIS
o Finite Element Model of Stud C300-4
Local imperfection
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

26. FINITE ELEMENT ANALYSIS
o Finite Element Model of Stud C300-4
About 76% of AISI
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

27. FINITE ELEMENT ANALYSIS
o Finite Element Model of Stud C300-4
P = 0 kN
P = 33.6 kN
P = 61.0 kN (peak load) P = 24.2 kN
Actual failure mode
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND

28. w
CONCLUSION
o The results indicated that the ultimate compressive strength obtained from the
experiment results were only 56-82% of the estimated strength based on the Direct
strength method (AISI 2007) at 76.7 kN
o The reduction of compressive strength indicates that just a little bit of inclined
section imperfections may significantly reduce the ultimate strength of the short
stud
o The results of stud-track specimens indicate that the ultimate compressive strength
of stud can be increased and more consistency by connecting the studs with tracks
at both ends
o The finite element model of 300mm length stud include inclined section
imperfection indicate good agreement with the experiment results
MAHANAKORN UNIVERSITY OF TECHNOLOGY, THAILAND