DESIGN OF PRECAST PRESTRESSED COMPOSITE BEAMS
POST/PRE TENSION
PROJECT ID :
BEAM TITLE :
NOTES :
DESIGNED BY :
INPUT DATA :
TRANSFER
STAGE
CONSTR.
STAGE
WORKING
STAGE
------------------------------------------------------W [ t / m' ]
=
SPAN (L) [m]
=
M = W x L ^2 /
OR M req. [AT W=0] =
0.29
0.15
0.96
7.50
7.50
7.50
8
8
8
Refer to section (D) in this sheet. [in the Input Data]
A-PROPERTIES OF A TRIAL SECTION
PRECAST
SECTION
B- LOADING
COMPOSITE SECTION
D (Ya+Yb) cm
21.00 AREA
cm2
2340.00 MG1
kg.cm
2.00E+05
AREA
cm
1170.00 Ya'
cm
0.69 MG2
kg.cm
1.05E+05
Ya
cm
-9.27 Yb'
cm
17.69 MQ1
kg.cm
6.75E+05
Yb
cm
11.73 Yc'
cm
6.259E+04 Yd'
cm
INERTIA cm4
Za
cm3
Zb
cm3
4
-6751.929 INERTIA cm
-12.31
0.69
2.010E+05
5335.131 Za'
cm3
Zb'
cm3
Zc'
cm3
-16327.875 Ftt
kg/cm2
Zd'
cm3
290273.333 Fct
kg/cm2
180
Ftw
kg/cm2
-29.2
Fcw
kg/cm2
140
290273.333 C- ALLOWABLE STRESSES
11358.522
-26.9
* Ftt & Fct indicate the allowable tension and compression stresses during the transfer stage respectively.
* Ftw & Fcw indicate the allowable tension and compression stresses during the working stage respectively.
D- ACTUAL MOMENT [M req.] AT EACH SECTION (FOR CASE OF W=0)
SECTION NO.
Distance
m.
Mg1
m.t
Mg2
m.t
Mq
m.t
WHERE :
1
0.00
0.00
0.00
8.74
2
0.75
0.00
0.00
8.74
3
1.50
0.00
0.00
8.74
4
2.25
0.00
0.00
8.74
5
3.00
0.00
0.00
8.74
6
3.75
0.00
0.00
8.74
7
4.50
0.00
0.00
8.74
8
5.25
0.00
0.00
8.74
9
6.00
0.00
0.00
8.74
10
6.75
0.00
0.00
8.74
11
7.50
0.00
0.00
8.74
Mg1 = Moment from O.W. of the precast beam only.
Mg2 = Moment from (O.W. of cast in situ slab) + (L.L. for construction) + (Shuttering System (if found)) only.
Mq = Moment from (The working L.L. - L.L. for construction) + (S.I.D.L.) only.
E-PROPERTIES OF PRESTRESSING TENDONS
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* PRESTRESSING FORCE OF ONE STRAND [WITH NO LOSSES]
7.044
ton
10
11.7
* % PERCENTAGE OF INITIAL LOSSES (SHORT TERM LOSSES ONLY) =
* % PERCENTAGE OF LONG TERM LOSSES ONLY
PRESTRESSING FORCE OF ONE STRAND (TON)
AFTER INITIAL LOSSES
AFTER ALL LOSSES
6.340
5.515
Cables Eccentricity
SECTION NO. / DISTANCE FROM THE START OF BEAM (m)
Layers of
Press. Cables
Layer [1]
No. of Cables
in each layer
4
Layer [2]
Layer [3]
Layer [4]
Layer [5]
Layer [6]
Layer [7]
1
0.00
2.50
Resultant Eccentricity
2
0.75
2.50
3
1.50
2.50
4
2.25
2.50
5
3.00
2.50
6
3.75
2.50
7
4.50
2.50
8
5.25
2.50
9
6.00
2.50
6.00
6.00
6.00
6.00
6.00
6.00
6.00
10
6.75
2.50
11
7.50
2.50
2.50
2.50
4.25
4.25
4.25
4.25
4.25
4.25
4.25
2.50
2.50
Final Eccentricity (e actual)
9.23
9.23
7.48
7.48
7.48
7.48
7.48
7.48
7.48
9.23
9.23
Total No. of cables at each Section
NOTES : 1- Cables Eccentricity Measured from the Lower Face of beam in centimeters.
2- Final Eccentricity (e actual) measured from the c.g. of the concrete section in centimeters.
3- In the Above Table Leave Cells Blank at the Sections where no Cables Specified.
OUTPUT DATA :
At the critical section (No. 6)
A- ECCENTRCITIES FOR A PRESTRESSING FORCE
.
Pt (No losses) (t)
Pt (initial loss) (t)
Pt (final loss) (t)
56.35
50.72
44.12
e1
(cm)
13.30
e2
(cm)
18.33
e3
(cm)
-9.08
e4
(cm)
emin
6.03
* Pt is the prestressing force for all cables at this section
(cm)
6.03
emax
(cm)
13.30
Inside feasible range
* e1, e2, e3, e4, emin & emax are measured from the c.g. of the concrete section in centimeters.
Calculated at the critical section (No. 6)
B- LIMITING PRESTRESSING FORCES
Ptmin
ton.=
15.810
Ptmax
ton.=
204.634
Pt choosen withen range
15.81036356
* Ptmin & Ptmax are the limiting prestressing forces for all cables at this section with No losses
C- NORMAL STRESSES
e (actual)
(at critical section NO. 6)
7.48
cm.
e choosen withen range
Transfer
Construc.
Working
stage
stage
stage
211976822.xls.ms_office - Rev. 0
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2/18/2014
fa' kg/cm2
16.84
34.13
31.80
fb' kg/cm2
76.90
42.25
-17.17
fc' kg/cm2
41.34
fd' kg/cm2
-2.33
D- PRESTRESSING FORCE vs ECCENTRICITY (at critical section NO. 6)
MAGNEL DIAGRAM
e cm
-5.000
0.000
5.000
10.000
15.000
20.000
25.000
30.000
35.000
250.000
150.000
100.000
Pt ton.
200.000
50.000
0.000
limits of e & Pt
choosen e & Pt
E- ECCENTRICITY AND NORMAL STRESSES ALONG BEAM SECTIONS
SECTION NO.
distance
m.
Mg1
kg.cm
Mg2
kg.cm
Mq
kg.cm
1
0.00
0.00E+00
0.00E+00
0.00E+00
2
0.75
7.21E+04
3.80E+04
2.43E+05
3
1.50
1.28E+05
6.75E+04
4.32E+05
4
2.25
1.68E+05
8.86E+04
5.67E+05
5
3.00
1.92E+05
1.01E+05
6.48E+05
6
3.75
2.00E+05
1.05E+05
6.75E+05
7
4.50
1.92E+05
1.01E+05
6.48E+05
8
5.25
1.68E+05
8.86E+04
5.67E+05
9
6.00
1.28E+05
6.75E+04
4.32E+05
10
6.75
7.21E+04
3.80E+04
2.43E+05
11
7.50
-1.78E-10
0.00E+00
-3.55E-10
Total No. of Strands
4
9.23
4
9.23
8
7.48
8
7.48
8
7.48
8
7.48
8
7.48
8
7.48
8
7.48
4
9.23
4
9.23
- NORMAL STRESSES ALONG BEAM [ the sign >> indicates OUT OF LIMIT VALUE]
Transfer
fa kg/cm2
-12.99
-2.31
6.15
12.09
stage
fb kg/cm2
65.55
52.03
90.42
82.91
Construct.
fa kg/cm2
-11.31
5.00
17.82
26.88
stage
fb kg/cm2
57.03
36.39
62.89
51.42
15.65
78.40
32.31
44.55
16.84
76.90
34.13
42.25
15.65
78.40
32.31
44.55
12.09
82.91
26.88
51.42
6.15
90.42
17.82
62.89
-2.31
52.03
5.00
36.39
-12.99
65.55
-11.31
57.03
Final Eccentricity (e actual)[cm]
211976822.xls.ms_office - Rev. 0
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2/18/2014
4.17
15.00
14.88
-0.84
16.33
24.86
26.46
-1.49
24.92
1.51
34.73
-1.95
30.08
-12.50
39.69
-2.23
31.80
-17.17
41.34
-2.33
30.08
-12.50
39.69
-2.23
24.92
1.51
34.73
-1.95
16.33
24.86
26.46
-1.49
4.17
15.00
14.88
-0.84
-11.31
57.03
0.00
0.00
12.93
33.31
-37.08
-11.62
15.78
36.15
-32.34
-1.46
11.88
16.90
-11.44
0.94
12.67
17.69
-10.13
3.77
13.15
18.17
-9.34
5.46
13.30
18.33
-9.08
6.03
13.15
18.17
-9.34
5.46
12.67
17.69
-10.13
3.77
11.88
16.90
-11.44
0.94
15.78
36.15
-32.34
-1.46
12.93
33.31
-37.08
-11.62
emin
cm
e (actual) cm
emax
cm
-11.62
9.23
12.93
-1.46
9.23
15.78
0.94
7.48
11.88
3.77
7.48
12.67
5.46
7.48
13.15
6.03
7.48
13.30
5.46
7.48
13.15
3.77
7.48
12.67
0.94
7.48
11.88
-1.46
9.23
15.78
-11.62
9.23
12.93
Ytop
Ybot
-9.27
11.73
-9.27
11.73
-9.27
11.73
-9.27
11.73
-9.27
11.73
-9.27
11.73
-9.27
11.73
-9.27
11.73
-9.27
11.73
-9.27
11.73
-9.27
11.73
e1
e2
e3
e4
fa'
fb'
fc'
fd'
kg/cm2
2
kg/cm
2
kg/cm
2
kg/cm
-11.31
57.03
0.00
0.00
Working
stage
cm
cm
cm
cm
cm
cm
CABLE PROFILE
-15.00
upper limit (e min)
-10.00
B
E
A
M
top of beam
-5.00
0.00
D
5.00
E
P
T 10.00
H
c.g. of tendons
bottom of beam
lower limit (e max)
15.00
20.00
0.00
0.75
1.50
2.25
3.00
3.75
4.50
5.25
6.00
6.75
7.50
BEAM LENGTH m
211976822.xls.ms_office - Rev. 0
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2/18/2014
13mm (0.5") strand
15mm (0.6") strand
NUMBER
DUCT DIA.
MIN. BREAKING
OF STRANDS
INT/EXT (mm)
LOAD (KN)
4
6
7
12
18
19
22
31
37
43
55
45/50
50/55
55/60
65/72
80/87
80/87
85/92
100/107
120/127
130/137
140/150
735
1102
1286
2204
3307
3490
4041
5695
6797
7899
10104
211976822.xls.ms_office - Rev. 0
NUMBER
DUCT DIA.
OF STRANDS INT/EXT (mm)
4
6
7
12
18
19
22
31
37
43
55
MIN. BREAKING
LOAD (KN)
50/55
60/67
60/67
80/87
95/102
95/102
110/117
130/137
140/150
150/160
170/180
Page 5 / 7
1043
1546
1825
3128
4693
4953
5735
8082
9646
11210
14339
2/18/2014
PRECAST SECTION
211976822.xls.ms_office
2/18/2014
PRECAST SECTION
JOINT
X (CM)
Y (CM)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
-45
45
45
15
15
60
60
-60
-60
-15
-15
-45
-45
0
0
3
3
17
17
21
21
17
17
3
3
0
-50
50
100
25
20
15
10
5
0
NOTE :
* ORIGIN OF THE "Y" AXIS MUST BE ON THE AXIS
OF SYMMETRIC OF THE PROPOSED SECTION.
* COORDINATES OF THE LAST JOINT MUST BE EQUAL
TO THE COORDINATES OF THE FIRST JOINT.
-No.of joints =
A
Xcg
Ycg
Ix
Iy
Ixy
Ya
Yb
-100
13
POINT NAME OF MAIN SEC.
AT TRANSFER STAGE
CORRESPONDS TO
JOINT NO.
a
b
7
2
[CM^2]
[CM]
[CM]
[CM^4]
[CM^4]
[CM^4]
[CM]
[CM]
1170.00
0.00
11.73
6.259E+04
7.898E+05
0.000E+00
-9.27
11.73
COMPOSITE SECTION
2/18/2014
211976822.xls.ms_office
COMPOSITE SECTION
JOINT
X (CM)
Y (CM)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
-60
60
60
15
15
60
60
-60
-60
-15
-15
-60
-60
0
0
3
3
17
17
30
30
17
17
3
3
0
-50
50
100
35
30
25
20
15
10
5
0
NOTE :
* ORIGIN OF THE "Y" AXIS MUST BE ON THE AXIS
OF SYMMETRIC OF THE PROPOSED SECTION.
* COORDINATES OF THE LAST JOINT MUST BE EQUAL
TO THE COORDINATES OF THE FIRST JOINT.
-No.of joints =
A
Xcg
Ycg
Ix
Iy
Ixy
Ya'
Yb'
Yc'
Yd'
-100
13
POINT NAME OF MAIN SEC.
AT WORKING STAGE
CORRESPONDS TO
JOINT NO.
a'
b'
c'
d'
5
2
7
6
[CM^2]
[CM]
[CM]
[CM^4]
[CM^4]
[CM^4]
[CM]
[CM]
[CM]
[CM]
2340.00
0.00
17.69
2.010E+05
2.336E+06
0.000E+00
0.69
17.69
-12.31
0.69
