Designing of Flat Plate Corner Panel by DDM
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Transcript of Designing of Flat Plate Corner Panel by DDM
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7/27/2019 Designing of Flat Plate Corner Panel by DDM
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 1
DESIGN OF CORNER FLAT PLATE PANEL
24.5
C1 C2
28.25
C5 C6
l1= 28.25
l2= 25.50
Columns are assumed to be 24 x 24 in2
CHECKING LIMITATIONS FOR USING DIRECT DESIGN
METHOD
1.
There are minimum three continuous spans in each direction OK2.
The panels are rectangular and ratio of longer to the shorter span is 1.154 OK3.
Adjacent spans in each direction do not differ by more than 1/3 of the longer span OK
4.
Columns are not offset from either axis between centerlines of successive columns OK
5.
Loads are uniform, and ratio of unfactored live to unfactored dead load is 0.44 OK
DETERMINING SLAB THICKNESS FOR FLAT-PLATE
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 2
From table 9.5(c) of the ACI Code, the minimum thickness of slab without interior beam,
without drop panel, exterior panel, with edge beam and fy= 60ksi,
h =
ln= (28.25*12 24) = 315 in
h =5
= .55
We take hs= 10 in
CALCULATING FACTORED LOADS
wL= 60 psfAs we take in assignment 1 and 2
wD= 10 psf + 150 pcf *
ft = 135 psf where 10 psf is dead load of vinyl tiles and 150
pcf is unit weight of concrete for slab
wU= 1.2(135) + 1.6(60) = 258 psf = 0.258 ksf
CHECKING TWO-WAY AND ONE-WAY SHEARS
A.Corner Column (C1)a)
Two-Way Shear
Assuming concrete cover and #5 bars, so average effective depth d is 0 0.75 5/8 = 8.625 in
b0= x + y
where,
x = 24 + 8.625/2
y = 24 + 8.625/2
so,
b0= 2(24 + 8.625/2)
b0= 56.25 in
VU= (XY xy) wUVU= (13.25*15.125 2.359375*2.359375)(0.258)VU= 50.27 kips
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 3
VC= (2 +
) b0d
VC= (2 +) (1) 000(56.25) (8.625)
VC= 185.33 kipsOR
VC= b0d
VC= 4(0.75)000(56.25) (8.625)VC= 92.67 kipsOR
VC= (
+ 2 ) b0d
VC= 0.75 (.
.+ 2 ) (1) 000(56.25) (8.625)
VC= 117 kips
So VC= 92.67 kips
Therefore VC> VU --- OKb)
One-Way Shear
Consider 1 ft strip at a distance d from the face of the column with the length
x,
x = 15.125 2 .
= 12.40625 ft
VU= wU(1*x)
VU= 0.258 (1*12.40625)
VU= 3.2 kips
VC= (2) b d
VC= (0.75) (2*1000) 12*8.625VC= 9.819 kips
Therefore VC> VU --- OK
B.Exterior Column (C2)
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 4
a)Two-Way Shear
Assuming concrete cover and #5 bars, so average effective depth d is 0 0.75 5/8 = 8.625 in
b0= x + 2y
where,
x = 24 + 8.625
y = 24 + 8.625/2
so,
b0= (24 + 8.625) + 2(24 + 8.625/2)
b0= 89.25 in
VU= (XY xy) wUVU= (24.5*15.125 2.359375*2.71875)(0.258)
VU= 93.95 kips
VC= (2 +
) b0d
VC= (2 +
) (1) 000(93.95) (8.625)
VC= 307.49 kipsOR
VC= b0d
VC= 4(0.75)000(93.95) (8.625)VC= 153.75 kipsOR
VC= (
+ 2 ) b0d
VC= 0.75 (.
.+ 2 ) (1) 000(93.95) (8.625)
VC= 182.73 kips
So VC= 153.75 kips
Therefore VC> VU --- OK
b) One-Way Shear
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 5
Consider 1 ft strip at a distance d from the face of the column with the length
x,
x = 15.125 2 .
= 12.40625 ft
VU= wU(1*x)
VU= 0.258 (1*12.40625)
VU= 3.2 kips
VC= (2) b d
VC= (0.75) (2*1000) 12*8.625VC= 9.819 kips
Therefore VC> VU --- OK
C.
Exterior Column (C5)a)
Two-Way Shear
Assuming concrete cover and #5 bars, so averageeffective depth d is 10 0.75 5/8 = 8.625 in
b0= 2x + y
where,
x = 24 + 8.625/2
y = 24 + 8.625
so,b0= 2(24 + 8.625/2) + (24 + 8.625)
b0= 89.25 in
VU= (XY xy) wUVU= (28.25*13.25 2.359375*2.71875)(0.258)VU= 94.92 kips
VC= (2 +
) b0d
VC= (2 +
) (1) 000(89.25) (8.625)
VC= 292.11 kipsOR
VC= b0d
VC= 4(0.75)000(89.25) (8.625)
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 6
VC= 146 kipsOR
VC= (
+ 2 ) b0d
VC= 0.75 (.
. + 2 ) (1) 000(89.25) (8.625)VC= 178.9 kips
So VC= 146 kips
Therefore VC> VU --- OKb)
One-Way Shear
Consider 1 ft strip at a distance d from the face of the column with the length
x,
x = 14.125 1 .= 12.40625 ft
VU= wU(1*x)
VU= 0.258 (1*12.40625)
VU= 3.2 kips
VC= (2) b d
VC= (0.75) (2*1000) 12*8.625
VC= 9.819 kips
Therefore VC> VU --- OK
D.Interior Column (C6)a)Two-Way Shear
Assuming concrete cover and #5 bars, so average effective depth d is 0 0.75 5/8 = 8.625 in
b0= 2x + 2y
where,
x = 24 + 8.625
y = 24 + 8.625
so,
b0= 2(24 + 8.625) + 2(24 + 8.625)
b0= 130.5 in
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 7
VU= (XY xy) wUVU= (28.25*24.5 2.71875*2.71875)(0.258)VU= 176.7 kips
VC= (2 +) b0d
VC= (2 +
) (1) 000(130.5) (8.625)
VC= 427.12 kipsOR
VC= b0d
VC= 4(0.75)000(130.5) (8.625)VC= 213.56 kipsOR
VC= (
+ 2 ) b0d
VC= 0.75 (.
.+ 2 ) (1) 000(130.5) (8.625)
VC= 248 kips
So VC= 213.56 kips
Therefore VC> VU --- OKb)
One-Way Shear
Consider 1 ft strip at a distance d from the face of the column with the length
x,
x = 14.125 1 .
= 12.40625 ft
VU= wU(1*x)
VU= 0.258 (1*12.40625)
VU= 3.2 kips
VC= (2) b dVC= (0.75) (2*1000) 12*8.625VC= 9.819 kips
Therefore VC> VU --- OK
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 8
CALCULATING THE TOTAL STATIC MOMENTS IN THE LONG
AND SHORT DIRECTION
LONG DIRECTION
M0L=
=
.. .
= 544 k.ft
SHORT DIRECTION
M0S=
=
.. .
= 462 k.ft
WIDTH OF COLUMN STRIP AND MIDDLE STRIP IN THE LONG
AND SHORT DIRECTIONLONG DIRECTION
Width of coumn strip = 0.25*2.5 = 6.25
Width of middle strip = 24.5 2(6.25) = 2.25
SHORT DIRECTION
Width of coumn strip = 0.25*2.5 = 6.25
Width of middle strip = 28.25 2(6.25) = 6
EFFECTIVE DEPTH IN EACH DIRECTION
To calculate effective depth in each direction, assume the steel bars in short direction are
placed on top of the bars in long direction.
Therefore,
LONG DIRECTION
d = 10 0.75 5/16 = 8.9375 in
SHORT DIRECTION
d = 10 0.75 5/8 5/16 = 8.3125 in
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 9
DISTRIBUTION OF TOTAL STATIC MOMENT INTO NEGATIVE
AND POSITIVE SPAN MOMENTS
Using ACI Code, Section 13.6.3
LONG DIRECTION
o Exterior Negative Moment = Mne= 0.26*544 = 141.44 k.ft
o Positive Moment Near Mid Span = Mp= 0.52*544 = 282.88 k.ft
o Interior Negative Moment = Mni= 0.7*544 = 380.8 k.ft
SHORT DIRECTION
o Exterior Negative Moment = Mne= 0.3*462 = 138.6 k.ft
o Positive Moment Near Mid Span = Mp= 0.5*462 = 231 k.ft
o
Interior Negative Moment = Mni= 0.7*462 = 323.4 k.ft
TRANSVERSE DISTRIBUTION OF MOMENTS
LONG DIRECTION
COLUMN STRIP MOMENTS
o Negative Moment at Exterior Support = 0.26*544 = 141.44 k.ft
o Positive Moment = 0.312*544 = 169.728 k.ft
o Negative Moment at Interior Support = 0.525*544 = 285.6 k.ft
MIDDLE STRIP MOMENTS
o Negative Moment at Exterior Support = 0
o Positive Moment = 0.208*544 = 113.152 k.ft
o Negative Moment at Interior Support = 0.175*544 = 95.2 k.ft
SHORT DIRECTION
COLUMN STRIP MOMENTS
o Negative Moment at Exterior Support = 1*138.6 = 138.6 k.ft
o Positive Moment = 0.6*231 = 138.6 k.ft
o Negative Moment at Interior Support = 0.75*323.4 = 242.55 k.ft
MIDDLE STRIP MOMENTS
o Negative Moment at Exterior Support = 138.6 138.6 = 0o Positive Moment = 231 138.6 = 92.4 k.fto Negative Moment at Interior Support = 323.4 242.55 = 80.85 k.ft
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 10
REINFORCEMENT DETAILS
Long Direction
Column Strip Middle Strip
Exterior Positive Interior Exterior Positive Interior
Mu (k.ft) 141.44 169.728 285.6 0 113.152 95.2
b(in) 73.5 73.5 73.5 147 147 147
d (in) 8.9375 8.9375 8.9375 8.9375 8.9375 8.9375
Ru (psi) 289.0906 346.9088 583.7407 0 115.6363 97.29012
Steel ratio ( ) 0.005634 0.006837 0.012102 0 0.002183 0.001831
As (sq.in) 3.700723 4.491036 7.950125 0 2.868682 2.405931
Min. As (sq.in) 1.323 1.323 1.323 2.646 2.646 2.646
Bars selected 12 no. 5 15 no. 5 26 no. 5 9 no. 5 10 no. 5 9 no. 5
Spacing 6.1 4.9 2.8 16.3 14.7 16.3
Short Direction
Column Strip Middle Strip
Exterior Positive Interior Exterior Positive Interior
Mu (k.ft) 138.6 138.6 242.55 0 92.4 80.85
b(in) 73.5 73.5 73.5 192 192 192
d (in) 8.3125 8.3125 8.3125 8.3125 8.3125 8.3125
Ru (psi) 327.4868 327.4868 573.1019 0 83.57736 73.13019
Steel ratio ( ) 0.006429 0.006429 0.011853 0 0.001569 0.001371
As (sq.in) 3.928101 3.928101 7.241541 0 2.504863 2.187867
Min. As (sq.in) 1.323 1.323 1.323 3.456 3.456 3.456
Bars selected 13 no. 5 13 no. 5 24 no. 5 12 no. 5 12 no. 5 12 no. 5
Spacing 5.6 5.6 3 16 16 16
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 11
DESIGN OF INTERIOR FLAT PLATE PANEL
24.5
C6 C7
28.25
C13 C14
l1= 28.25
l2= 25.50
Columns are assumed to be 24 x 24 in2
CHECKING LIMITATIONS FOR USING DIRECT DESIGN
METHOD
6.
There are minimum three continuous spans in each direction OK7.
The panels are rectangular and ratio of longer to the shorter span is 1.154 OK8.
Adjacent spans in each direction do not differ by more than 1/3 of the longer span OK
9.
Columns are not offset from either axis between centerlines of successive columns OK
10.
Loads are uniform, and ratio of unfactored live to unfactored dead load is 0.44 OK
DETERMINING SLAB THICKNESS FOR FLAT-PLATE
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 12
From table 9.5(c) of the ACI Code, the minimum thickness of slab without interior beam,
without drop panel, interior panel, and fy= 60ksi,
h =
ln= (28.25*12 24) = 315 in
h =5
= .55
We take hs= 10 in
CALCULATING FACTORED LOADS
wL= 60 psfAs we take in assignment 1 and 2
wD= 10 psf + 150 pcf *
ft = 135 psf where 10 psf is dead load of vinyl tiles and 150
pcf is unit weight of concrete for slab
wU= 1.2(135) + 1.6(60) = 258 psf = 0.258 ksf
CHECKING TWO-WAY AND ONE-WAY SHEARS
A. Interior Column (C6)a)
Two-Way Shear
Assuming concrete cover and #5 bars, so average effective depth d is 10 0.75 5/8 = 8.625 in
b0= 2x + 2y
where,
x = 24 + 8.625
y = 24 + 8.625
so,
b0= 2(24 + 8.625) + 2(24 + 8.625)
b0= 130.5 in
VU= (XY xy) wUVU= (28.25*24.5 2.71875*2.71875)(0.258)VU= 176.7 kips
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 13
VC= (2 +
) b0d
VC= (2 +
) (1) 000(130.5) (8.625)
VC= 427.12 kipsOR
VC= b0d
VC= 4(0.75)000(130.5) (8.625)VC= 213.56 kipsOR
VC= (
+ 2 ) b0d
VC= 0.75 (.
.+ 2 ) (1) 000(130.5) (8.625)
VC= 248 kips
So VC= 213.56 kips
Therefore VC> VU --- OKb)
One-Way Shear
Consider 1 ft strip at a distance d from the face of the column with the length
x,
x = 14.125 1 .
= 12.40625 ft
VU= wU(1*x)
VU= 0.258 (1*12.40625)
VU= 3.2 kips
VC= (2) b d
VC= (0.75) (2*1000) 12*8.625VC= 9.819 kips
Therefore VC> VU --- OK
B. Interior Column (C7)a)
Two-Way Shear
Assuming concrete cover and #5 bars, so average effective depth d is 0 0.75 5/8 = 8.625 in
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 14
b0= 2x + 2y
where,
x = 24 + 8.625
y = 24 + 8.625
so,
b0= 2(24 + 8.625) + 2(24 + 8.625)
b0= 130.5 in
VU= (XY xy) wUVU= (28.25*24.5 2.71875*2.71875)(0.258)VU= 176.7 kips
VC= (2 +
) b0d
VC= (2 +
) (1) 000(130.5) (8.625)
VC= 427.12 kipsOR
VC= b0d
VC= 4(0.75)000(130.5) (8.625)VC= 213.56 kipsOR
VC= (
+ 2 ) b0d
VC= 0.75 (.
.+ 2 ) (1) 000(130.5) (8.625)
VC= 248 kips
So VC= 213.56 kips
Therefore VC> VU --- OKb)
One-Way Shear
Consider 1 ft strip at a distance d from the face of the column with the length
x,
x = 14.125 1 .
= 12.40625 ft
VU= wU(1*x)
VU= 0.258 (1*12.40625)
VU= 3.2 kips
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 15
VC= (2) b d
VC= (0.75) (2*1000) 12*8.625VC= 9.819 kips
Therefore VC> VU --- OK
C. Interior Column (C13)a)Two-Way Shear
Assuming concrete cover and #5 bars, so average effective depth d is 0 0.75 5/8 = 8.625 in
b0= 2x + 2y
where,
x = 24 + 8.625
y = 24 + 8.625
so,
b0= 2(24 + 8.625) + 2(24 + 8.625)
b0= 130.5 in
VU= (XY xy) wUVU= (17.625*24.5 2.71875*2.71875)(0.258)VU= 109.5 kips
VC= (2 + ) b0d
VC= (2 +
) (1) 000(130.5) (8.625)
VC= 427.12 kipsOR
VC= b0d
VC= 4(0.75)000(130.5) (8.625)VC= 213.56 kips
OR
VC= (
+ 2 ) b0d
VC= 0.75 (.
.+ 2 ) (1) 000(130.5) (8.625)
VC= 248 kips
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 16
So VC= 213.56 kips
Therefore VC> VU --- OKb)
One-Way Shear
Consider 1 ft strip at a distance d from the face of the column with the length
x,
x = 14.125 1 .
= 12.40625 ft
VU= wU(1*x)
VU= 0.258 (1*12.40625)
VU= 3.2 kips
VC= (2) b d
VC= (0.75) (2*1000) 12*8.625VC= 9.819 kips
Therefore VC> VU --- OK
D. Interior Column (C14)c)Two-Way Shear
Assuming concrete cover and #5 bars, so average effective depth d is 10 0.75 5/8 = 8.625 in
b0= 2x + 2ywhere,
x = 24 + 8.625
y = 24 + 8.625
so,
b0= 2(24 + 8.625) + 2(24 + 8.625)
b0= 130.5 in
VU= (XY xy) wUVU= (17.625*24.5 2.71875*2.71875)(0.258)VU= 109.5 kips
VC= (2 +
) b0d
VC= (2 +
) (1) 000(130.5) (8.625)
VC= 427.12 kips
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 17
OR
VC= b0d
VC= 4(0.75)000(130.5) (8.625)VC= 213.56 kips
OR
VC= (
+ 2 ) b0d
VC= 0.75 (.
.+ 2 ) (1) 000(130.5) (8.625)
VC= 248 kips
So VC= 213.56 kips
Therefore VC> VU --- OKd)
One-Way Shear
Consider 1 ft strip at a distance d from the face of the column with the length
x,
x = 14.125 1 .
= 12.40625 ft
VU= wU(1*x)
VU= 0.258 (1*12.40625)
VU= 3.2 kips
VC= (2) b d
VC= (0.75) (2*1000) 12*8.625VC= 9.819 kips
Therefore VC> VU --- OK
CALCULATING THE TOTAL STATIC MOMENTS IN THE LONG
AND SHORT DIRECTION
LONG DIRECTION
M0L=
=
.. .
= 544 k.ft
SHORT DIRECTION
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 18
M0S=
=
.. .
= 462 k.ft
WIDTH OF COLUMN STRIP AND MIDDLE STRIP IN THE LONG
AND SHORT DIRECTIONLONG DIRECTION
Width of coumn strip = 0.25*2.5 = 6.25
Width of middle strip = 24.5 2(6.25) = 2.25
SHORT DIRECTION
Width of column strip = 0.25*2.5 = 6.25
Width of middle strip = 28.25 2(6.25) = 6
EFFECTIVE DEPTH IN EACH DIRECTION
To calculate effective depth in each direction, assume the steel bars in short direction are
placed on top of the bars in long direction.
Therefore,
LONG DIRECTION
d = 10 0.75 5/16 = 8.9375 in
SHORT DIRECTION
d = 10 0.75 5/8 5/16 = 8.3125 in
DISTRIBUTION OF TOTAL STATIC MOMENT INTO NEGATIVE
AND POSITIVE SPAN MOMENTS
Using ACI Code, Section 13.6.3
LONG DIRECTION
o Negative Moment = 0.65*544 = 353.6 k.ft
o Positive Moment = 0.35*544 = 190.4 k.ft
SHORT DIRECTION
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 19
o Negative Moment = 0.65*462 = 300.3 k.ft
o Positive Moment = 0.35*462 = 161.7 k.ft
PERCENTAGES OF STATIC MOMENTS IN COLUMN AND
MIDDLE STRIPSLONG DIRECTION
COLUMN STRIP MOMENTS
o Negative Moment = 0.49*544 = 266.56 k.ft
o Positive Moment = 0.21*544 = 114.24 k.ft
MIDDLE STRIP MOMENTS
o Negative Moment = 0.16*544 = 87.04 k.ft
o
Positive Moment = 0.14*544 = 76.16 k.ft
SHORT DIRECTION
COLUMN STRIP MOMENTS
o Negative Moment = 0.49*462 = 226.38 k.ft
o Positive Moment = 0.21*462 = 97.02 k.ft
MIDDLE STRIP MOMENTS
o Negative Moment = 0.16*462 = 73.92 k.ft
o Positive Moment = 0.14*462 = 64.68 k.ft
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Assignment No. 4 [CE 405: REINFORCED CONCRETE DESIGNII]
Muhammad Ahsan Khan|CE119 20
REINFORCEMENT DETAILS
Long Direction
Column Strip Middle Strip
Negative Positive Negative Positive
Mu (k.ft) 266.56 114.24 87.04 76.16
b(in) 73.5 73.5 147 147
d (in) 8.9375 8.9375 8.9375 8.9375
Ru (psi) 544.8247 233.4963 88.95097 77.8321
Steel ratio ( ) 0.011195 0.004503 0.001672 0.00146
As (sq.in) 7.354214 2.957992 2.196569 1.91836
Min. As (sq.in) 1.323 1.323 2.646 2.646
Bars selected 24 no. 5 10 no. 5 9 no. 5 9 no. 5
Spacing 3 7.3 16.3 16.3
Short Direction Column Strip Middle Strip
Negative Positive Negative Positive
Mu (k.ft) 226.38 97.02 73.92 64.68
b(in) 73.5 73.5 192 192
d (in) 8.3125 8.3125 8.3125 8.3125
Ru (psi) 534.8951 229.2408 66.86189 58.50416
Steel ratio ( ) 0.010967 0.004417 0.001252 0.001094
As (sq.in) 6.700279 2.698878 1.998215 1.745976
Min. As (sq.in) 1.323 1.323 3.456 3.456
Bars selected 22 no. 5 9 no. 5 12 no. 5 12 no. 5Spacing 3.3 8.2 16 16