AS3600-2009 Wall Design
AS3600-2009 Wall Design
AS3600-2009 Wall Design
(Received: 6 April 2011; Received revised form: 2 November 2011; Accepted: 7 November 2011)
Abstract: Forty seven reinforced concrete walls with various opening configurations
are tested in both one-way and two-way action. The test panels, with a slenderness
ratio of 30, 35 or 40, were subjected to a uniformly distributed axial load at an
eccentricity of one sixth of the wall thickness (tw /6). Apart from highlighting the
experimental set-up; typical crack patterns, failure modes, and load-deflection
behaviour of test panels are also reported. Actual test failure loads are compared to
ultimate load predictions using the Australian standard wall design equation and also
a recently derived formula specifically for walls with openings. The code equation is
found to be inadequate for the many cases investigated whereas the derived formula
was verified as being adequate in predicting failure load of walls with openings.
Key words: concrete walls, openings, axial load, code method, slenderness ratio, design equation.
1. INTRODUCTION
Reinforced concrete walls with eccentric axial loads
can be designed using code methods that include the
use of simplified formulae or the more accurate column
design procedure. In many cases more rigorous
methods such as utilising finite element analysis can
also be employed. The design of walls as structural
members is now just as significant as beams, slabs and
columns. This is due to the modern day popularity of
tilt-up construction, shear walls and concrete cores in
tall buildings. The popularity has spread to Australia
where prior to the 1990s limited experimental research
was performed on concrete wall panels. More recently,
significant research projects focusing on the load
capacity of solid concrete walls that have been
undertaken in Australia include the work of Fragomeni
(1995), Sanjayan and Maheswaran (1999) and Doh
(2002). Since then introductory research was undertaken
by Doh and Fragomeni (2006) on the load capacity of
1345
Behavior of Axially Loaded Concrete Wall Panels with Openings: An Experimental Study
Side support
Curvature
Crack
(a) One-way action wall with
opening
1346
(1)
(2)
where
Pu is the ultimate load of an identical one-way
and two-way solid wall panel defined as
0.55 [ Ag fc + ( f y fc) Asv ]{1 [ H /(32t w )]2} and 0.67 f Ag
{1 [ L/(120 t w )]2}{1 + 0.12( H / L )} respectively. k1 and k2
were respectively, obtained from the test results, 1.25
and 1.22 for one-way action and 1.02 and 1.00 for twoway action.
Figure 2 identifies the important symbols used where
G1 & G2 = centres of gravity of wall cross section with
H
G1
G3
G2
L0
Elevation
L0
L/2
t
G1
G2
G3
Cross - section
(3)
where
Nu is the ultimate load of an identical one-way and
two-way solid wall panel defined as Nu = 2.0fc0.7(tw
1.2e 2ea) which is a modified version of the AS3600
equation and intended for panels with high slenderness
ratios.
1347
Behavior of Axially Loaded Concrete Wall Panels with Openings: An Experimental Study
1348
CL
40
CL
450
CL
1200
300
300
1200
450
450
CL
450
450
300
1200
450
40
Figure 3. Details of typical test wall panels with one and two
openings (dimensions in mm)
Size of panel
H L tw (mm)
Opening size
Ho Lo n (mm)
H/tw
O50W1C1.2
O70W1C1.2
O90W1C1.2
O95W1C1.2
O45W1C1.4
O90W1C1.4
O95W1C1.4
O50W1C1.6
O90W1C1.6
O50W2C1.2
O70W2C1.2
O95W2C1.2
O45W2C1.4
O90W2C1.4
O95W2C1.4
O50W2C1.6
O70W2C1.6
O90W2C1.6
T50W1C1.2
T70W1C1.2
T45W1C1.4
T90W1C1.4
T95W1C1.4
T50W1C1.6
T70W1C1.6
T90W1C1.6
T50W2C1.2
T70W2C1.2
T90W2C1.2
T45W2C1.4
T90W2C1.4
T95W2C1.4
T50W2C1.6
T70W2C1.6
T90W2C1.6
1200 1200 40
300 300 1
30
1400 1400 40
350 350 1
35
1600 1600 40
400 400 1
40
1200 1200 40
300 300 2
30
1400 1400 40
350 350 2
35
1600 1600 40
400 400 2
40
1200 1200 40
300 300 1
30
1400 1400 40
350 350 1
35
1600 1600 40
400 400 1
40
1200 1200 40
300 300 2
30
1400 1400 40
350 350 2
35
1600 1600 40
400 400 2
40
Cure
(days)
fcm
(MPa)
45
28
55
49
36
45
57
30
45
30
28
49
47
45
57
30
61
45
29
54
49
55
44
29
91
48
32
54
49
48
55
55
20
91
30
53.0
67.7
95.1
96.2
38.0
80.0
99.3
47.0
97.1
50.3
67.7
96.2
44.5
80.0
99.3
51.1
74.1
97.1
50.3
74.1
45.5
95.1
96.2
50.3
75.1
93.6
50.3
74.1
97.1
45.5
95.1
80.0
50.3
75.1
94.2
Nu,test
(kN)
309.0
426.7
470.9
488.5
191.3
300.2
426.1
294.3
503.3
191.3
242.8
308.1
150.7
244.3
350.8
195.7
279.0
347.3
706.3
953.5
732.8
1303.7
1298.4
1030.1
1390.6
1583.3
618.0
633.4
665.1
662.2
918.2
759.9
647.5
988.8
1236.1
Nu.test/
fcLefftw
0.162
0.175
0.138
0.141
0.120
0.089
0.102
0.130
0.108
0.158
0.149
0.133
0.120
0.109
0.126
0.120
0.118
0.112
0.390
0.361
0.383
0.326
0.321
0.427
0.386
0.352
0.512
0.356
0.285
0.520
0.345
0.339
0.336
0.411
0.410
n is number of openings.
*Effective length, Leff = L Lo where Lo is length of opening(s).
1349
Behavior of Axially Loaded Concrete Wall Panels with Openings: An Experimental Study
1350
5. RESULTS
5.1. Crack Patterns
Figures 7 to 14 show the crack patterns observed on a
typical selection of test panels after failure. These panels
give an indicative insight of cracking behaviour observed.
1351
Behavior of Axially Loaded Concrete Wall Panels with Openings: An Experimental Study
1352
500
O45W1C1.4
Top
Left
Bottom
Right
Loads (kN)
400
300
200
100
0
0
4
Deflection (mm)
500
O95W1C1.4
400
Loads (kN)
300
200
Top
Left
Bottom
Right
100
0
0
4
Deflection (mm)
5.2. Deflection
Typical load versus lateral deflection relationships for
the wall panels tested in both one and two-way actions
are shown in Figures 15 to 22. They show that the
deflections at the wall centre are generally in proportion
to adjacent points. That is, load deflection paths for left
and right transducers are similar, as are readings for top
and bottom transducers in these figures. This indicates
the data gives a reasonably accurate indication of load
versus lateral deflection measurement.
The curves for the one-way action panels with
openings (see Figures 15 to 18) give a very good
indication of load deflection characteristics acting in
single curvature. This is typified by the maximum
1353
Behavior of Axially Loaded Concrete Wall Panels with Openings: An Experimental Study
1400
400
045W2C1.4
1200
1000
Loads (kN)
300
Loads (kN)
T90W1C1.4
Top
Left
Bottom
Centre
200
800
600
Top
Left
Bottom
Right
400
100
200
0
0
4
Deflection (mm)
4
6
8
Deflection (mm)
10
12
400
O90W2C1.4
1000
T45W2C1.4
800
200
Loads (kN)
Loads (kN)
300
Top
Left
Bottom
Centre
100
600
400
Top
Left
Bottom
Centre
200
0
0
4
Deflection (mm)
8
0
0
10
12
14
Deflection (mm)
1000
800
T90W2C1.4
800
Loads (kN)
Loads (kN)
1000
Top
Left
Bottom
Right
1200
600
400
200
600
400
Top
Left
Bottom
Centre
200
0
0
6
8
Deflection (mm)
10
12
1354
0
0
6
8
Deflection (mm)
10
12
14
1355
Behavior of Axially Loaded Concrete Wall Panels with Openings: An Experimental Study
Table 2. Predicted and actual failure loads of panels with one or two openings
Panel
designation
Size of panel
H L tw (mm)
Opening size
Ho Lo n (mm)
H/tw
O50W1C1.2
O70W1C1.2
O90W1C1.2
O95W1C1.2
O45W1C1.4
O90W1C1.4
O95W1C1.4
O50W1C1.6
O90W1C1.6
O50W2C1.2
O70W2C1.2
O95W2C1.2
O45W2C1.4
O90W2C1.4
O95W2C1.4
O50W2C1.6
O70W2C1.6
O90W2C1.6
T50W1C1.2
T70W1C1.2
T45W1C1.4
T90W1C1.4
T95W1C1.4
T50W1C1.6
T70W1C1.6
T90W1C1.6
T50W2C1.2
T70W2C1.2
T90W2C1.2
T45W2C1.4
T90W2C1.4
T95W2C1.4
T50W2C1.6
T70W2C1.6
T90W2C1.6
1200 1200 40
300 300 1
30
1400 1400 40
350 350 1
35
1600 1600 40
400 400 1
40
1200 1200 40
300 300 2
30
1400 1400 40
350 350 2
35
1600 1600 40
400 400 2
40
1200 1200 40
300 300 1
30
1400 1400 40
350 350 1
35
1600 1600 40
400 400 1
40
1200 1200 40
300 300 2
30
1400 1400 40
350 350 2
35
1600 1600 40
400 400 2
40
1356
Nu,test
(kN)
309.0
426.7
470.9
488.5
191.3
300.2
426.1
294.3
503.3
191.3
242.8
308.1
150.7
244.3
350.8
195.7
279.0
347.3
706.3
953.5
732.8
1303.7
1298.4
1030.1
1390.6
1583.3
618.0
633.4
665.1
662.2
918.2
759.9
647.5
988.8
1236.1
NuEq1
(kN)
NuEq3
(kN)
NuEq1/
Nu,test
NuEq3/
Nu,test
91.6
117.0
164.3
166.2
0
0
0
0
0
57.9
78.0
110.8
0
0
0
0
0
0
673.6
992.3
636.4
1330.1
1345.4
695.3
1038.2
1293.9
449.1
661.6
866.9
424.2
886.7
745.9
555.7
692.1
868.1
290.1
344.4
436.9
440.4
213.2
404.9
471.0
286.0
475.1
185.1
227.9
291.5
177.7
268.0
311.7
200.7
260.2
314.4
676.2
886.6
725.5
1215.5
1225.4
878.5
1162.9
1362.7
548.9
688.7
775.5
541.5
821.1
753.4
659.2
921.2
1175.7
0.30
0.27
0.35
0.34
0
0
0
0
0
0.30
0.32
0.36
0
0
0
0
0
0
0.95
1.04
0.87
1.02
1.04
0.67
0.75
0.82
0.73
1.04
1.30
0.64
0.96
0.98
0.86
0.70
0.70
0.94
0.81
0.93
0.90
1.11
1.35
1.11
0.97
0.94
0.97
0.94
0.95
1.18
1.10
0.89
1.03
0.93
0.91
0.96
0.93
0.99
0.93
0.94
0.85
0.84
0.86
0.89
1.09
1.17
0.82
0.89
0.99
1.02
0.93
0.95
CL
600
450
600
1200 mm
200 300
300
O65W1W1.2/T65W1W1.2
700
200 300
1200 mm
O65W1L1.2/T65W1L1.2
O65W1UL1.2/T65W1UL1.2
200 300
700
1200 mm
O65D1L1.2/T65D1L1.2
360
480
240
240
600
480
450
450
O65D1C1.2/T65D1C1.2
CL
CL
300
450
300
450
300
450
1200 mm
700
1200 mm
CL
CL
1200 mm
300
450
300
450
300
1200 mm
450
300
450
CL
300
CL
360
480
600
240
1200 mm
240
450
1200 mm
T65W1SL1.2
T65W1SB1.2
Figure 23. Details of typical test wall panels with various openings (dimensions in mm)
Table 3. Predicted and actual failure loads of panels with varying opening configurations
Panel
designation
Size of panel
H L tw (mm)
Opening size
Ho Lo n (mm)
fcm
(MPa)
Nu,test
(kN)
NuEq3
(kN)
O65W1W1.2
O65W1L1.2
O65W1UL1.2
O65D1C1.2
O65D1L1.2
T65W1W1.2
T65W1L1.2
T65W1UL1.2
T65D1C1.2
T65D1L1.2
T65W1SL1.2
T65W1SB1.2
1200 1200 40
1200 1200 40
1200 1200 40
1200 1200 40
1200 1200 40
1200 1200 40
1200 1200 40
1200 1200 40
1200 1200 40
1200 1200 40
1200 1200 40
1600 1600 40
300 600 1
300 300 1
300 300 1
750 300 1
750 300 1
300 600 1
300 300 1
300 300 1
750 300 1
750 300 1
240 240 1
240 240 1
60.3
60.3
60.3
60.3
60.3
56.4
65.0
62.4
65.0
56.4
62.4
56.4
176.0
258.4
257.8
243.7
206.0
682.2
737.5
715.7
676.9
582.7
794.6
721.0
210.2
287.5
287.5
317.6
287.5
511.2
741.6
720.7
809.6
671.4
834.4
755.2
7. CONCLUSIONS
An experimental study was undertaken on a total of forty
seven reinforced concrete walls with openings in one and
two-way action. Loaded with an eccentricity of tw/6,
these half-scale specimens had high slenderness ratios
between 30 and 40. The test results indicate that failure
loads and crack patterns depend on the opening
configuration and support conditions. In effect the failure
loads of two-way panels with openings are about 2 to 4
NuEq3/
Nu,test
1.19
1.11
1.16
1.30
1.40
0.75
1.01
1.01
1.20
1.15
1.05
1.05
1357
Behavior of Axially Loaded Concrete Wall Panels with Openings: An Experimental Study
1358