Post on 25-Feb-2023
65
REFERENCES
[1]. Dhammika K. Wijayasinghe,” a case study of the “Sahaspura” slum relocation
project,” M.S Thesis, Institute for Housing and Urban Development Studies,
Colombo, Sri Lanka,2010.
[2]. Channa Kasturisinghe, (2003, July 8). Invests Rs. 25m in hollow core slab
facility.DailyNewsBusiness(SriLanka).[online].Available:http://archives.dailyn
ews.lk/2003/07/08/bus11.html.
[3]. D. B. P. S. Vidyarathne,” Household Income and Expenditure,” Department of
Census and Statistics, Ministry of Finance and Planning, Sri Lanka, Tech.Rep.
ISBN 978-955-577-719-3, 2009/10.
[4]. W.P.S. Dias, “Useful life of buildings,” Department of Civil Engineering
University of Moratuwa, Sri Lanka, Tech.Rep.4 June 2003.
[5]. R.I.Gilbert and N.C.Mickleborough, Design of Prestressed Concrete. School of
Civil Engineering: Sydney, Australia, 1990.
[6]. Bently Staad.(1999).“Advantages of Post-Tensioning,” [Online].Available:
http://www.ehow.com/info_7932750_advantages-vs-post-tension-slab.html.
[7]. Jim Rogers. (2008, Nov. 25). Post-Tensioned Slab. Webmaster Mag.[Online].
Available: http://www.concreteconstruction.net /concrete-construction /post-
tensioned-slab-on-ground-foundations.aspx.
[8]. Evaluation and Certification Service, LLC. (2006).What is Post-Tensioning.
[Online].Available:http://www.buildersshow.com/Documents/course_handouts
/PostTensioned%20Concrete%20in%20Residential%20Construction.pdf.
[9]. Jim Rogers. (2012 Sep. /Oct.). Concrete Floors. Webmaster Mag.
[Online].Available:http://www.freemagazines.co.za/magazines/floors10/files_f
loors10 /assets/basic-html/page38.html.
[10]. Manamohan R Kalgal, Post-tensioned Concrete in Building Sector [Online].
Available:http://www.sefindia.org/forum/files /pt_in_building_sector_839.pdf.
[11]. Ed Cross, Post-Tensioning in Building Structures. [Online].Available:http://ww
w.ptia.net.au/Documents/Post-tensioning%20%20Building % 20Structures.pdf.
[12]. Boskey Vishal Bahoria and Dhananjay K.Parbat .(2013 ,February).Analysis and
Design of RCC and Post-tensioned Flat Slabs Considering Seismic
Effect.IACSIT International Journel of Engineering and Technology,Vol.5
No.1. [Online]. Available:http://www.ijetch.org/papers/500-C10011.pdf.
66
[13] CCL’s DesignTeam.(2011,Oct).”Post-TensionedSlab,”[online].Available:http:
http://www.cclint.com/sites/default/files ccl_ptslabsbrochureeng.pdf.
[14]. G.D.Palmer, “What are the Advantages & Disadvantages of a Conventional
Concrete Slab Vs. a Post Tension Slab?,” [Online]. Available:
http://www.ask.com/question/what-is-a-post-tension-slab
[15]. Nainar Uma Sentil .(2008-09).”Concrete Basics.org's Newsletter,” [online].
Available: http://www.concretebasics.org/lccb/ptslab.php.
[16]. Kevin. (2007, November). “Post-tensioned or reinforced: Structural
Engineering,”[online]. Available: http://seaint.blogspot.com/2007/11/re-post-
tensioned-or-reinforced.html.
[17]. Dhammika Senarath Kumara, (2011). Post Tensioned Concrete Floors [Online].
Available:http://www.civil.mrt.ac.lk/conference/ICSECM_2011/SEC-11-8.pdf.
[18]. Bijan O. Aalami and Jennifer D.Jurgens. (2003, March). Guidelines for the
Design of Post-Tensioned Floors. Webmasters Mag.
[Online].Available:http://www.adaptsoft.com/resources/Aalami_CI_Mar03_pa
per.pdf.
[19]. Jim Rogers.(2009, September). “Post Tensioning Ironworker Certification
Program,” [online article]. Available : www.ironworkercertification.com.
[20]. B.Dixit Raj .(2011,July). Post Tensioning In Building Structures. Department
of Civil Engineering Gokaraju Rangaraju Institute of Engineering &
Technology Nizampet Road, Hyderabad-500090. [online].
Available:http://grietinfo.in/projects/MINI/civil/Civil_Miniproject_Dixit.pdf.
[21]. Design and Construction, Code of Practice BS 8110: Part 1& Part 3: 1985.
68
Appendix B
Conventional Reinforced Slab
Design Spread Sheet for 7mx9m
Panel for the Live Load of 1.5kN/m2
69
Appendix C
Conventional Reinforced Beam Design
Spread Sheet for 7m Span for the
Live Load of 1.5kN/m2
70
Appendix D
Required Quantities of Materials for
Conventional Reinforced Slabs and Beams for the
Live Load of 1.5kN/m2
71
Appendix E
Unit Rate Calculation for Conventional Reinforced
Slab and Beams for 21mx27m
Area for the Live Load of 1.5kN/m2
72
Appendix F
Post -Tensioned Slab Design
Spread Sheet for 7mx9m Panel for the
Live Load of 1.5kN/m2
73
Appendix G
Conventional Reinforced Beam Design
Spread Sheet for 7m for the
Live Load of 1.5kN/m2 for the Post-Tensioned Slab
74
Appendix H
Required Quantities of Materials for the
Post-Tensioned Slabs and the Conventional Reinforced
Beams for the Live load of 1.5kN/m2
75
Appendix I
Unit Rate Calculation for Post-Tensioned Slab and
Conventional Reinforced Beams for 21m x 27m
Area for the Live Load of 1.5kN/m2
76
Appendix J
Basic Prices for Accessories for the
Post-Tensioned Slab
77
Appendix K
Work Study Spread Sheet for
Three Multi-Storied Buildings
Appendix A- Sample Questionnaire: Study on Viability of adopting Post Tensioned Slab Construction in Sri
Lanka
Research Supervisor : Dr. K. Baskaran, Department of Civil Engineering, University of Moratuwa Page 1
Appendix A- Sample Questionnaire
Research Subject: Study on Viability of adopting Post Tensioned Slab Construction in Sri Lanka
1. Information on Respondent
Please place a tick () as appropriate
a. Your Profession
I. Engineer ( )
II. Architect ( )
III. Quantity Surveyor ( )
Iv. Any other (Please specify) …………………………………………
b. Your Experience in the Construction Industry
I. Less than 5 years ( )
II. Between 5 and 10 years ( )
III. More than 10 years ( )
c. Your current employment is in
I. Government Department ( )
II. State Corporation, Board etc., ( )
III. Private Sector ( )
Iv. Any other (Please specify)………………………………………………
d. Your role in the Construction Sector
I. Contractor ( ) II. Consultant ( ) III. Client ( ) Iv. Any other (Pl specify)…………………………………………..……….
Appendix A- Sample Questionnaire: Study on Viability of adopting Post Tensioned Slab Construction in Sri
Lanka
Research Supervisor : Dr. K. Baskaran, Department of Civil Engineering, University of Moratuwa Page 2
2. Your views on the construction practices of “multi-storied buildings in Sri
Lanka”
Please strike off what is not applicable. Answer could be more than one.
a. What are the main super structure elements in a multi-storied
building?
i. Walls Yes/No
ii. Columns Yes/No
iii. Beams and slab Yes/No
iv. Roof Yes/No
v. Any other (Pl specify)……………………………………………..…
b. In general, what is the most costly super structure element in your
experience?
i. Walls Yes/No
ii. Columns Yes/No
iii. Beams and slabs Yes/No
iv. Roof Yes/No
v. Any other (Pl specify)……………………………………………..…
3. Your views on slab construction in “multi-storied buildings in Sri Lanka”
Please place a tick () as appropriate.
a. What is the main structural material frequently used for slab at
present?
i. Reinforced concrete ( )
ii. Steel ( )
iii. Masonry ( )
iv. Timber ( )
v. Any other (Pl specify)………………………………………………………..…
Appendix A- Sample Questionnaire: Study on Viability of adopting Post Tensioned Slab Construction in Sri
Lanka
Research Supervisor : Dr. K. Baskaran, Department of Civil Engineering, University of Moratuwa Page 3
4. IF the answer to question number 3 is Reinforced Cement Concrete, please answer the following questions Please strike off what is not applicable. Answer could be more than one.
a. What are the advantages in using the Reinforced Cement Concrete
for slabs?
I. Durability Yes/No
II. Less maintenance cost Yes/No
III. Low repair cost Yes/No
vi. Any other (Pl
specify)…………………………………………………………………………..…
b. What are the disadvantages of using Reinforced Cement Concrete for
slabs in your experience?
i. Un-economical beyond certain thickness Yes/No
ii. Un-economical when spans increase Yes/No
iii. Any other (Pl
specify)…………………………………………………………………………..…
5. Please express your involvement in the “Post tensioned slabs”, based on
Your experience in Sri Lanka or Abroad
Please strike off what is not applicable. Answer could be more than one.
a. What is your experience on post tensioned slabs?
I. Designing of “Post Tensioned slabs” Yes/No
II. Construction of “Post Tensioned slabs” Yes/No
III. Any other (Pl
specify)…………………………………………………………………………..…
b. What are the advantages of using “Post Tensioned slabs”, in your
experience?
Please place a tick () as appropriate. Answer could be more than
one.
Appendix A- Sample Questionnaire: Study on Viability of adopting Post Tensioned Slab Construction in Sri
Lanka
Research Supervisor : Dr. K. Baskaran, Department of Civil Engineering, University of Moratuwa Page 4
Advantages Yes No
1 Longer Spans are possible
2 Overall saving on Structural Cost
3 Reduced Floor to Floor Height
4 Deflection Free Slabs
5 Water tight Slabs
6 Early Stripping of formwork
7 Easy handling of materials
8 Lighter foundation designs
9 Speedier of Construction
10 Any other (Please explain below)
…………………………………………………………………………………………………….
……………………………………………………………………………………………………..
…………………………………………………………………………………………………….
……………………………………………………………………………………………………..
c. What are the disadvantages of “Post Tensioned slabs”, in your
opinion?
Please strike off what is not applicable. Answer could be more than
one.
I. Needs the services of trained operatives for
installation and tensioning which involves
additional trade on site
Yes/No
II. Involves additional site works such as drilling
holes on the side shutters and fixing anchorage
blocks to the formwork
Yes/No
III. Special materials such as anchorages, ducts
and tendons will have to be specially procured
and stored on site
Yes/No
Appendix A- Sample Questionnaire: Study on Viability of adopting Post Tensioned Slab Construction in Sri
Lanka
Research Supervisor : Dr. K. Baskaran, Department of Civil Engineering, University of Moratuwa Page 5
IV. Special equipment such as stressing jacks
and grout pumps will have to be
procured initially, maintained and moved
from one position to another within site
and from one site to the other
Yes/ No
V. Any others ………………………..
6. Do you have any idea on cost comparison between
“Reinforced Cement Concrete and Post Tensioned Concrete
slab? Yes/ No
If Yes, please express your views and explain :
……………………………………………………………………………………………
……………………………………………………………………………………………
…………………………………………………………………………………………….
……………………………………………………………………………………………
…………………………………………………………………………………………….
7. Do you think that the post tensioned slab construction in
multi-storied building projects is viable in Sri Lanka?
Yes/ No
If Yes , please express your views and explain :
……………………………………….…………………………………………………
……………………………………………………………………………………………
Appendix B- Conventional reinforced slab design spread sheet for 7mx9m panel for live load of 1.5kN/m2
Sheet No.
Two way edge supported Slab( Live load=1.5 kN/m2
)
BS 8110
Part 1:1985 Ly = 9 m
Lx = 7 m
C D
Short Span of the slab Lx = 7 m
Long Span of the slab Ly = 9 m
Density of the concrete s = 24
Concrete compressive strength fcu = 25
Diameter of r/f = 12 mm
Span/Effective depth = 40
Table 3.5 Cover for 1 hour fire resistance = 20 mm
Live load = kN/m2
Partition = kN/m2
Finishes = kN/m2
Effective depth d = mm
Slab thickness h = h= mm
dshort = mm Spacing
dlong = mm
Aspect Ratio = ly/lx ==
Self weight = kN/m2
Design load = kN/m2
kN/m3
0.5
N/mm2
200
Output
1.3
11.22
Date
Reference Calculations
1.5
UNIVERSITY OF
MORATUWA
Course of
Study
M.Eng/PGDip.in Structural
Engineering Design
Component Conventional slab design
4.8
175
200
162
174.0
1.0
Page 1 of 4
Appendix B- Conventional reinforced slab design spread sheet for 7mx9m panel for live load of 1.5kN/m2
Sheet No.
Output
Date
Reference Calculations
UNIVERSITY OF
MORATUWA
Course of
Study
M.Eng/PGDip.in Structural
Engineering Design
Component Conventional slab design
Table 3.15 βsx = One long Edge discontinuous
βsy =
βex =
βey =
msx = kNm/m
msy = kNm/m
mex = kNm/m
mey = kNm/m
Design for reinforcement
Short way mid span
M/bd2
=
From the chart ,Part 3
100As/bd =
As =
Number of bar =
Max.spacing 3d = mm
Asmin = mm2
Provide r/f at = mm spacing Number of bar prov 5 h= mm
Asprov = mm2
Spacing
Check deflection
Table 3.10 BasicSpan/eff.depth =
fs = N/mm2
Modification Factor = F1
F1 = < 2
Allowable Span/eff.depth =
Actual span /eff.depth =
Deflection Criteria Satisfied
250
204
40.2
26
1.8
0.23
48
20.34
0.85
0.028
0.037
25.84
15.39
0.047
0.062
400.2
34.09
260
3.54
522
565.2
mm2
Table 3.27
250
Page 2 of 4
Appendix B- Conventional reinforced slab design spread sheet for 7mx9m panel for live load of 1.5kN/m2
Sheet No.
Output
Date
Reference Calculations
UNIVERSITY OF
MORATUWA
Course of
Study
M.Eng/PGDip.in Structural
Engineering Design
Component Conventional slab design
Short way continuous edge
M/bd2
=
From the chart ,Part 3
100As/bd =
As =
Number of bar =
Max.spacing 3d = mm
Asmin = mm2
Provide r/f at = mm spacing Number of bar prov 5 h= mm
Asprov = mm2
Spacing
Table 3.16 Check Shear
βvx ==
Vsx = kN/m
v = N/mm2
Table 3.9 0.79(100As/bd)1/3
=
=
=
ϒm ==
vc = N/mm2
Long way mid span
M/bd2
=
From the chart ,Part 3
100As/bd =
As = mm2
Number of bar =
Max.spacing 3d = mm
Asmin = mm2
Provide r/f at = mm spacing Number of bar prov 4 h= mm
Asprov = mm2
Spacing
200
300
mm2
1.1
4.46
0.29
300
2.44
452.2
0.17
275.4
0.59
260
486
1.23
0.54
0.47
0.54
1.25
No shear r/f required
Table 3.27
Table 3.27
522
260
504.6
200
(400/d)1/4
(fcu/25)1/3
565.2
1.00
36.9
0.212
Page 3 of 4
Appendix B- Conventional reinforced slab design spread sheet for 7mx9m panel for live load of 1.5kN/m2
Sheet No.
Output
Date
Reference Calculations
UNIVERSITY OF
MORATUWA
Course of
Study
M.Eng/PGDip.in Structural
Engineering Design
Component Conventional slab design
Long way, continuous edge
M/bd2
=
From the chart ,Part 3
100As/bd =
As = mm2
Number of bar =
Max.spacing 3d = mm
Asmin = mm2
Provide r/f at = mm spacing Number of bar prov 4 h= mm
Asprov = mm2
Spacing
Table 3.16 Check Shear
βvx ==
Vsx = kN/m
v = N/mm2
Table 3.9 0.79(100As/bd)1/3
=
(400/d)1/4
=
(fcu/25)1/3
=
ϒm ==
vc = N/mm2
300
452.2
28.3
0.175
0.52
1.00
1.25
0.52
No shear r/f required
300
3.15
260
1.25
0.78
0.36
0.22
356.4
Table 3.27
486
Page 4 of 4
Appendix C-Conventional reinforced beam design spread sheet for 7m for 1.5 kN/m2
Sheet No.
Two way edge supported Slab ( Live load=1.5 kN/m2
)
7m x 9m Panel
Edge Beam(7m)
Short span lx = 7 m
Long span ly = 9 m
Table 3.10 Span/Effective depth = 23 For Span< 10 m
Required effective depth d = mm
Beam height h = mm
Beam width b = mm
Diameter of r/f φ = 16 mm
Cover c = 25 mm
Calculated effective depth de = mm
Concrete compressive strength fcu == 25 N/mm2
Loading from the conventional slab
Live load = kN/m2
Partition = kN/m2
Finishes = kN/m2
Self weight = kN/m2
Table 3.16 Two adjacent edges discontinuous, βvy =
Total dead load from the slab = kN/m
Self wt of beam = 4 kN/m
Total dead load for the beam = kN/m
Total live load from the slab = kN/m
Design load = kN/m
From SAP 2000, Analysis
Msag = kNm
Mhog = kNm
1.5
BS
8110:Part1:
1985
304
600
Conventional beam design
300
567
Reference Calculations Output
UNIVERSITY OF MORATUWA
Component
Course of
Study
M.Eng/PGDip.in Structural Engineering
Design
26.47
1.0
4.8
0.26
11.47
15.8
0.5
2.73
115
130
Page 1 of 5
Appendix C-Conventional reinforced beam design spread sheet for 7m for 1.5 kN/m2
Sheet No.
Conventional beam design
Reference Calculations Output
UNIVERSITY OF MORATUWA
Component
Course of
Study
M.Eng/PGDip.in Structural Engineering
Design
Design for span moment(Sag)
Clause 3.4.4.4 K=M/bd2fcu = <
Compression r/f is not required
Z = < 0.95d
As = mm2
Provide = 3 T16 = 3
Aspro = mm2
Check for deflection
Table 3.10 Basic Span/eff.depth = 23
fs = N/mm2
M/bd2
=
Table 3.11 Modification Factor =
Allowable Span/eff.depth =
Actual span /eff.depth =
Deflection =
Design for support moment(hog)
Clause 3.4.4.4 K=M/bd2fcu = <
Compression r/f is not required
Z = < 0.95d
As = mm2
Provide = 4 T16 = 4
Aspro = mm2
Shear force = kN
Shear Stress v = N/mm2
Clause 3.4.5.3 0.87(fcu)1/2
= N/mm2
>
So, no crushing occurs
Table 3.9 0.79(100As/bd)1/3
=
(400/d)1/4
=
0.156
535.2
537
602.9
256
0.048
1.2
1.430
32.9
12.3
Satisfied
0.054 0.156
531
612
804
112
0.66
4.35
0.62
0.66
1.0
Page 2 of 5
Appendix C-Conventional reinforced beam design spread sheet for 7m for 1.5 kN/m2
Sheet No.
Conventional beam design
Reference Calculations Output
UNIVERSITY OF MORATUWA
Component
Course of
Study
M.Eng/PGDip.in Structural Engineering
Design
=
ϒm =
vc = N/mm2
<
= N/mm2
0.5vc = N/mm2
Table 3.8 < v < vc +0.4
Diameter of a link = 10 mm
Ae = mm
2
fyv = N/mm
2
Asv/sv =
sv = mm
Provide 10 mm Diameter of a link R 10 At
Mild steel at = Spacing stirrups mm
1.25
0.49 0.66
0.89
0.25
0.5vc
78.5
250
vc +0.4
275275 mm
0.55
285
(fcu/25)1/3
1.00
Page 3 of 5
Appendix C-Conventional reinforced beam design spread sheet for 7m for 1.5 kN/m2
Sheet No.
Conventional beam design
Reference Calculations Output
UNIVERSITY OF MORATUWA
Component
Course of
Study
M.Eng/PGDip.in Structural Engineering
Design
All the spans are loaded with the distributed load of 26.5 kN/m (1.4Gk +1.6Qk) on the SAP 2000
modal
Bending Moment Diagram for the distributed load of 26.5 kN/m (1.4Gk +1.6Qk) from the SAP 2000
modal Analysis
Shear Force Diagram for the distributed load of 26.5 kN/m (1.4Gk +1.6Qk) from the SAP 2000 modal
Analysis
Page 4 of 5
Appendix C-Conventional reinforced beam design spread sheet for 7m for 1.5 kN/m2
Sheet No.
Conventional beam design
Reference Calculations Output
UNIVERSITY OF MORATUWA
Component
Course of
Study
M.Eng/PGDip.in Structural Engineering
Design
Bending Moment Diagram for the distributed load of 26.5 kN/m (1.4Gk +1.6Qk) and 15.8 kN/m from
the SAP 2000 modal Analysis
Spans are loaded with the distributed load of 26.5 kN/m (1.4Gk +1.6Qk) and 15.8 kN.m 1.0 Gk on the
SAP 2000 modal
Shear Force Diagram for the distributed load of 26.5 kN/m (1.4Gk +1.6Qk) and 15.8 kN/m from the
SAP 2000 modal Analysis
Page 5 of 5
Appendix D - Required Quantities of Materials for Conventional Reinforced Slabs and Beams for the Live
Load of 1.5 kN/m2
9X9 Panel
( 27 mX27m)
8X9 Panel
( 24 mX27m)
7X9 Panel
( 21 mX27m)
6X9Panel
( 18 mX27m)
5X9Panel
( 15 mX27m)
223 168 148 110 80
Tor bar 25mm Dia(Ton) 6.62376 7.527 4.93308 3.31188 2.70972
Tor bar 20mm Dia(Ton) 2.13408 0 1.24488 1.83768 1.60056
Tor bar 16mm Dia(Ton) 1.16736 0.29184 0.51072 0.3648 0.21888
Tor bar 12mm Dia(Ton) 13.69104 10.23792 6.73728 0.03696 0
Tor bar 10mm Dia (Ton) 3.47988 2.550678 2.372982 5.538192 5.1828
Mild steel 10mm Dia (Ton) 0.799632 0.445474 0.423262 0.469537 0.3702
Quantity of the Steel(Ton) 27.895752 21.052912 16.222204 11.559049 10.08216
666 598 518 453 366
394 309 279 234 183
Required Quantities of Materials for Conventional Reinforced Slabs and Beams for
the Live Load of 1.5 kN/m2
Formwork(m2) for Slab
Formwork(m2) for Beam
Material type
Concrete Grade 25/m3
Page 1 of 1
Appendix E - Unit rate calculation for conventional reinforced slab and beams for
21mx27m area for the live load of 1.5 kN/m2
QuantityCost(Rs)/
unit
Total
cost(Rs)
148 13,250 1961000
4.93308 149,000 735029
1.24488 149,000 185487
0.51072 149,000 76097
6.73728 149,000 1003855
2.372982 149,000 353574
0.423262 149,000 63066
518 1100 569800
279 1250 348750
9342
Supply and placing concrete Grade 25(m3)
Supply and tieing Tor bar 25mm Dia(Ton)
Supply and tieing Tor bar 20mm Dia(Ton)
Supply and tieing Tor bar 16mm Dia(Ton)
Supply and tieing Tor bar 12mm Dia(Ton)
Unit rate calculation for conventional reinforced slab and beams for
21mx27m area for the live load of 1.5 kN/m2
Supply and tieing Tor bar 10mm Dia(Ton)
7X9 Panel ( 21 mX27m)
Supply and tieing mild steel10mm Dia(Ton)
Total cost (Rs) per m2
Items
For Live load of 1.5 kN/m2
Supply , Fixing and Removing Formwork(m2)
for Beam
Supply , Fixing and Removing Formwork(m2)
for Slab
Page 1 of 1
Appendix F-Post-tensioned slab design spread sheet for 7mx9m panel for the live load of 1.5 kN/m2
Sheet No.
Two way edge supported Slab
Design of Prestressed Concrete
By
R.I.Gilbert
N.C. Micklebrough
Ly = 9 m
Lx = 7 m
C D
Short Span of the slab Lx = m
Long Span of the slab Ly = m
Thickness of the slab h = mm
Density of the concrete s = kN/m3
Concrete compressive strength = N/mm2
Concrete tensile strength = N/mm2
Elastic Modulus of concrete = N/mm2
Characteristric strength of steel fb = N/mm2
Elastic Modulus of prestressing steel = = N/mm2
Flat Ducted tendons
Strands diametre = N/mm2
Area of a strand Ap = mm2
No of strands per tendons = 3
Reference Calculations Output
UNIVERSITY OF
MORATUWA
Course of
Study
M.Eng/PGDip.in Structural
Engineering Design
Component Post Tensioning slab design Date
35
24
7
9
160
1840
195000
12.7
100
30000
3.5
AS 3600-
1988
Page 1 of 9
Appendix F-Post-tensioned slab design spread sheet for 7mx9m panel for the live load of 1.5 kN/m2
Sheet No.
Reference Calculations Output
UNIVERSITY OF
MORATUWA
Course of
Study
M.Eng/PGDip.in Structural
Engineering Design
Component Post Tensioning slab design Date
Size of the duct
Width = 75 mm
Height = 19 mm
From top to Centre = 7 mm
Conrete cover = 25 mm
Live = kN/m2
Partitions = kN/m2
Finshes = kN/m2
Self weight of floor slab ( Calculated) = kN/m2
0.5
3.84
1.0
1.5
Page 2 of 9
Appendix F-Post-tensioned slab design spread sheet for 7mx9m panel for the live load of 1.5 kN/m2
Sheet No.
Reference Calculations Output
UNIVERSITY OF
MORATUWA
Course of
Study
M.Eng/PGDip.in Structural
Engineering Design
Component Post Tensioning slab design Date
Calculation
The Maximum Depth to CGS for the short -span
dx == mm = mm
= 0 mm
= mm
= mm
The cable drape in the short-span direction
hx = mm
The Maximum Depth to CGS for the Long -span
dy = mm = mm
= mm
= mm
= mm
The cable drape in the Long-span direction
hy = mm
= Dwelling
= 30 %
= kN/m2
The Total sustained load wsus = kN/m2
Alpha = 2
External Balancing load wb = 5 kN/m2
wpx = kN/m2
wpy = kN/m2
Height of CGS above the CGC at the
support on LHS
67
43
64.5
104
43
43
123
0.45
The live load assumed to be
sustained as per AS 3600-1988
5.8
For 1 long edge
discontinuous
Height of CGS above the CGC at the
support on LHS
Height of CGS above the CGC at the
support onRHS
Height of CGS below the CGC at the
span
Height of CGS above the CGC at the
support on RHS 43
Height of CGS below the CGC at the
span 24
The transverse load exerted by the
tendons in the short-span direction
2.89
The transverse load exerted by the
tendons in the Long-span direction
2.11
123
104
Page 3 of 9
Appendix F-Post-tensioned slab design spread sheet for 7mx9m panel for the live load of 1.5 kN/m2
Sheet No.
Reference Calculations Output
UNIVERSITY OF
MORATUWA
Course of
Study
M.Eng/PGDip.in Structural
Engineering Design
Component Post Tensioning slab design Date
Px = kN/m
Py = kN/m
The time dependent losses = 15 %
The prestress in each direction Pxi = kN/m
Pyi = kN/m
The immediate losses at theJack
In the x direction = 8 %
In the y direction = 12 %
The prestress in each direction Pxj = kN/m
Pyj = kN/m
The breaking load per tendon = kN
= kN
The required tendon spacing in each direction
Sx = mm
Sy = mm
Select tendon spacing = = mm
Pxj = Pyi = kN = kN
And at mid span,after all losses,
Px = kN
Py = kN
The load to be balanced is revised
wpx = kN/m2
wpy = kN/m2
Now,the external Balancing load wb = kN/m2
= kN
0.85
0.92
0.88
319
3.5
2.1
Maximum force to be applied to a stress-relieved post
tensioned during the stressing operation,if the limit is applied
on the Jacking forces/tendon
The effective prestress in each
direction 274
323
376
351
427
5.6
427
334
319
The avarage efective prestress after
losses in each direction isassumed
1100
0.85 fbAp 469
552
319
1338
1099
The revised prestressing forces at the jack
per metre width are
427
1100
Page 4 of 9
Appendix F-Post-tensioned slab design spread sheet for 7mx9m panel for the live load of 1.5 kN/m2
Sheet No.
Reference Calculations Output
UNIVERSITY OF
MORATUWA
Course of
Study
M.Eng/PGDip.in Structural
Engineering Design
Component Post Tensioning slab design Date
=
Final shrinkage strain =
Dead load = kN/m2
ψs =
wu = kN/m2
β = Ref Page 387
The maximum moment MCD = kNm/m
I = mm4
Z = mm3
Check for cracking
Stress at top = N/mm2
Compression
Stress at Bottom = N/mm2
Compression
Average compressive stress level 2.0- 3.0 Mpa Satisfied
Check for deflection
Maximum total deflection
wus = kN/m
Short term deflection v = mm
The sustained portion of unbalanced load = kN/m
Deflection due to vsus = mm
Creep induced deflection vcr = 0 mm
Shrinkage-induced curvature xsh = mm
Shrinkage-induced deflection vsh = mm
vtot = = mm
9E-07
0.6
-1.6
-2.40
0.36
341333333
0.6
0.4
5.34
0.057
2.5
In the x-direction over support CD,the concrete stresses in the
top and the bottom fibres are
4266666.7
0.10
0.1
5.0
4.1
Under this unbalanced load,the maximum moment occurs over
the beam support CD by using the moment coefficiants for
edge-supported slabs in Table 10.2
Final Creep coefficient for concrete in
post tension slab
v+vcr+vsh
-1.7
0.0005
The maximum unbalanced transverse load to be
considered for short-term serviceability for
Page 5 of 9
Appendix F-Post-tensioned slab design spread sheet for 7mx9m panel for the live load of 1.5 kN/m2
Sheet No.
Reference Calculations Output
UNIVERSITY OF
MORATUWA
Course of
Study
M.Eng/PGDip.in Structural
Engineering Design
Component Post Tensioning slab design Date
The maximum panel deflection vtot = mm
= mm
K = Page 427
The unbalanced load wu = kN/m2
The sustained part of the unbalanced load
wus = kN/m2
Le/D <=
[wu+3wus]1/3
[(vtot/Le)1000Ec]1/3
=
[wu+3wus]1/3
=
Le/D <=
D = mm Satisfied Satisfied
Check for Flexural Strength
Dead load = kN/m2
Live load = kN/m2
The Factored design load as per AS 3600-1988
w* = kN/m2
βx = Page 386
βy =
The deflection at the centre of the slab panel will be
approximately 30% less than this owing to the torsional stiffness
of the slab which has been ignored in the above analysis.
137
5.34
The design moments at mid=span in each direction are
obtained are obtained from Eq 10.7 with values taken
from Table 10.1
0.046
0.028
3.83
It is of value to examin the slab thickness
predicted,if the limiting deflection is taken
For this edge-supported slab panel,the slab
system factor is taken from table 11.4 ,K
2.4
1.5
8.9
0.6
51
3.83
0.4
25.3
1.19
K[(vtot/Le)1000Ec]1/3
Page 6 of 9
Appendix F-Post-tensioned slab design spread sheet for 7mx9m panel for the live load of 1.5 kN/m2
Sheet No.
Reference Calculations Output
UNIVERSITY OF
MORATUWA
Course of
Study
M.Eng/PGDip.in Structural
Engineering Design
Component Post Tensioning slab design Date
= kNm/m
= kNm/m
The maximum design moment occurs over the beam support CD
= kNm/m
Depth to neutral axis at ultimate
h = Ap = mm2
b = Ep = N/mm2
h' = 43 Ec = N/mm2
i = mm4
ece =
Pe = kN/m ept = 0.003(R62-dn)/dn
epe =
epu = 0.00612+0.003(R62-dn)/dn
c = 0.85X35X1000X0.800Xdn= 23800 dn
The resultant tensile force T = Apσpu
Horizontal equilibrium requires that C=T
= 87.3dn
σpu(N/mm2)
21
The depth to the neutral axis at ultimate = mm
However, the maximum limitting value =
= mm
The tensile force in the steel = kN/m
Mu = kNm/m
φMu = kNm/m
> kNm/m
Hence,Conventional r/f is not required to supplement the
prestressed steel over the beam support CD
0.4d
49.2
500
57.3
45.88
26.2
0.0207 1835
Trial dn epu
σpu
21.0
273
195000
0.00600
12.25
0.00012
1000 mm
mm
341333333
30000
319
MDC 26.15
160 mm
Mx*
My*
20.12
Page 7 of 9
Appendix F-Post-tensioned slab design spread sheet for 7mx9m panel for the live load of 1.5 kN/m2
Sheet No.
Reference Calculations Output
UNIVERSITY OF
MORATUWA
Course of
Study
M.Eng/PGDip.in Structural
Engineering Design
Component Post Tensioning slab design Date
Checking for strength at other critical section
At mid-span in the x-direction:
= kNm/m
= kNm/m
d = mm
Hence,no additional r/f is required
At mid-span in the y-direction:
= 21 mm
However, the maximum limitting value =
= mm
The tensile force in the steel = kN/m
Mu = kNm/m
=
> kNm/m
Hence,no additional r/f is required
At the short continuos supports;
= kNm/m
φMu = kNm/m
> 16 kNm/m
Hence,no additional r/f is required
Ckeck Shear strength
V* = Lx w*/2
= kN/m
s = Pe
A
= N/mm2
Q =
Q/Ib =
t = Q Vt/Ib
s1 = 0.33(fc)1/2
s1 = N/mm2
From the equation 5.11 from the text book
The depth to the neutral axis at
ultimate
20.1
φMu
Mx*
57.3
φMu 38.27
12.2
My* 16
45.88
31
-2.08
3200000
0.4d
41.6
500
47.8
1.95
9.38E-06
123
Page 8 of 9
Appendix F-Post-tensioned slab design spread sheet for 7mx9m panel for the live load of 1.5 kN/m2
Sheet No.
Reference Calculations Output
UNIVERSITY OF
MORATUWA
Course of
Study
M.Eng/PGDip.in Structural
Engineering Design
Component Post Tensioning slab design Date
(s1- s /2 )2
= Eqn----1
(s /2)2
= Eqn----2
Eqn---1 -Eqn---2 =
t2
=
t =
Vt =
= kN/m
f =
= kN/m
Clearly V* is much less than fVuc
and the shear strength is ample here
Shear strength at all other sections are also satisfactory.
Shear is rarely a problem in edge-supported slabs.
0.8
fVuc 240
7.882
7.882
2.807
t/Q/Ib
299
8.968
1.087
Page 9 of 9
Appendix G-Conventional reinforced beam desin spread sheet for the live load of 1.5 kN/m2
for the post tensioned slab
Sheet No.
7m x 9m Panel
Edge Beam(7m)
Short span lx = 7 m
ly = 9 m
Table 3.10 Span/Effective depth = 26 For Span< 10 m
Required effective depth d = mm
Beam height h = mm
Beam width b = mm
Diameter of r/f φ = 16 mm
Table 3.4 Cover c = 35 mm
Calculated Effective depth de = mm
Concrete compressive strength fc == 35 N/mm2
Loading from the post-tensioned slab
Live load = kN/m2
Partition = kN/m2
Finish = kN/m2
Self weight = kN/m2
Table 3.16 Two adjacent edges discontinuous, βvy =
Total dead load from the slab = kN/m
Total live load from the slab = kN/m
Self wt of beam = kN/m
Total Dead load for the beam = kN/m
Total live load from the slab = kN/m
Design load = kN/m
BS
8110:Part1:
1985
2.73
23.52
550
1.0
3.84
0.26
Reinforced Beam Design
Reference Output
UNIVERSITY OF
MORATUWA
Component
9.72
Course of
Study
M.Eng/PGDip.in Structural Engineering
Design
3.96
0.5
300
13.7
507
2.73
Two way edge supported post tensioned Slab
for the Live load of 1.5 kN/m2
1.5
269
Page 1 of 5
Appendix G-Conventional reinforced beam desin spread sheet for the live load of 1.5 kN/m2
for the post tensioned slab
Sheet No.
Reinforced Beam Design
Reference Output
UNIVERSITY OF
MORATUWA
Component
Course of
Study
M.Eng/PGDip.in Structural Engineering
Design
From the sap 2000, analysis Msag = kNm
Mhog = kNm
Design for Span moment(Sag)
K=M/bd2fcu = <
Compression r/f is not required
Z = < 0.95d
As = mm2
Provide = 3 3
Aspro = mm2
Check for deflection
Table 3.10 Basic Span/eff.depth = 26
fs = N/mm2
M/bd2
=
Table 3.11 Modification Factor =
Allowable Span/eff.depth =
Actual span /eff.depth =
Deflection =
Design for Support moment(hog)
K=M/bd2fcu = <
Compression r/f is not required
Z = < 0.95d
As = mm2
Provide= 4 4
Aspro = mm2
Shear force = kN
Shear Stress v = N/mm2
0.87(fcu)1/2
= N/mm2
>
So, no crushing occurs
T16=
T16=
482
13.8
5.15
Satisfied
484.5
0.65
0.043
115
0.65
36.0
0.156
596
99
804
0.038 0.156
531
253
1.3
1.384
602.9
103
Clause
3.4.4.4
Clause
3.4.4.4
Clause
3.4.5.3
Page 2 of 5
Appendix G-Conventional reinforced beam desin spread sheet for the live load of 1.5 kN/m2
for the post tensioned slab
Sheet No.
Reinforced Beam Design
Reference Output
UNIVERSITY OF
MORATUWA
Component
Course of
Study
M.Eng/PGDip.in Structural Engineering
Design
Table 3.9 0.79(100As/bd)1/3
=
(400/d)1/4
=
=
ϒm =
vc = N/mm2
<
= N/mm2
0.5vc = N/mm2
Table 3.8 < v < vc +0.4
Diametre of a link = 10 mm
Ae = mm
2
fyv = N/mm
2
Asv/sv =
sv = mm
Provide 10 mm Diameter of a link R 10 At
Mild steel at = Spacing stirrups250 mm
0.65
0.29
0.97
0.64
1.25
0.57
1.12
1.0
250
0.55
285
(fcu/25)1/3
250
vc +0.4
0.5vc
78.5
Page 3 of 5
Appendix G-Conventional reinforced beam desin spread sheet for the live load of 1.5 kN/m2
for the post tensioned slab
Sheet No.
Reinforced Beam Design
Reference Output
UNIVERSITY OF
MORATUWA
Component
Course of
Study
M.Eng/PGDip.in Structural Engineering
Design
All the spans are loaded with the distributed load of 23.5 kN/m (1.4Gk +1.6Qk) on the SAP
2000 modal
Bending Moment Diagram for the distributed load of 23.5 kN/m (1.4Gk +1.6Qk) from the
SAP 2000 modal Analysis
Shear Force Diagram for the distributed load of 23.5 kN/m (1.4Gk +1.6Qk) from the SAP
2000 modal Analysis
Page 4 of 5
Appendix G-Conventional reinforced beam desin spread sheet for the live load of 1.5 kN/m2
for the post tensioned slab
Sheet No.
Reinforced Beam Design
Reference Output
UNIVERSITY OF
MORATUWA
Component
Course of
Study
M.Eng/PGDip.in Structural Engineering
Design
Spans are loaded with the distributed load of 23.5 kN/m (1.4Gk +1.6Qk) and 13.7kN.m 1.0
Gk on the SAP 2000 modal
Bending Moment Diagram for the distributed load of 23.5 kN/m (1.4Gk +1.6Qk) and 13.7
kN/m from the SAP 2000 modal Analysis
Shear Force Diagram for the distributed load of 23.5 kN/m (1.4Gk +1.6Qk) and 13.7kN/m
from the SAP 2000 modal Analysis
Page 5 of 5
Appendix H - Required quantities of materials for post-tensioned slabs and beams for
the live of 1.5 kN/m2
9X9Panel
( 27 mX27m)
8X9 Panel
( 24 mX27m)
7X9Panel
( 21 mX27m)
6X9 Panel
( 18 mX27m)
5X9 Panel
( 15 mX27m)
189 146 124 92 75
6.0216 6.99432 4.09932 2.70972 2.70972
1.06704 0 1.06704 1.7784 1.42272
1.16736 0.29184 0.7296 0.29184 0.32832
0.805802 0.686721 0.322691 0.318989 0.299862
0.799632 0.447325 0.702146 0.389944 0.3702
1.50 1.45 1.35 1.20 1.07
4.1 3.7 2.8 2.5 1.6
56 53 44 44 44
56 53 44 44 44
168 159 132 126 88
168 159 132 126 88
1512 1347 1082 909 896
12 12 12 12 12
666 598 518 450 366
394 304 276 230 178
2 2 2 2 2
Formwork(m2) for Slab
Tor bar 25mm Dia(Ton)
Formwork(m2) for Beam
Tor bar 20mm Dia(Ton)
Tor bar 16mm Dia(Ton)
Tor bar 10mm Dia(Ton)
Mild steel bar 10mm
Dia(Ton)
Live end Anchor block(nos)
Multi Strands Jacks/Month
Required quantities of materials for post-tensioned slabs and beams for the
live of 1.5 kN/m2
Labours for PT work( laying
duct,inserting stands and
Jacking)
Sheath/Duct (m)
Concrete Grade 35(m3)
Material Items
Minimum R/F Tor steel
10mm Dia(Ton)
12.7mm Strand(Ton)
Recess former (nos)
Wedges(nos)
Dead end Anchor block(nos)
Page 1 of 1
Appendix I - Unit rate calculation for the post-tensioned slab and beams for
21mx27m area for the live of 1.5 kN/m2
Quantity Cost(Rs)/
unit
Total
cost(Rs)
124 14,750 1829000
4.09932 149,000 610799
1.06704 149,000 158989
0.7296 149,000 108710
0.322691 149,000 48081
0.702146 149,000 104620
1.35 149,000 201333
2.8 150,000 426563
44 1700 74800
44 280 12320
132 120 15840
132 1000 132000
1082 170 183940
12 1200 14400
518 1100 569800
276 1250 345000
2 20000 20000
8548
Multi Strands Jacks(RS)/Month
7X9Panel ( 21 mX27m)
Labours for PT work( laying duct,inserting
stands and Jacking)
Suppy Sheath/Duct (m)
Supply , Fixing and Removing
Formwork(m2) for Slab
Total cost (Rs)/m2
Items
Supply and tieing mild steel 10mm
Dia(Ton)
Minimum R/F Tor steel 10mm Dia(Ton)
Suppy 12.7mm Strand(Ton)
Supply Live end Anchor block(nos)
Supply recess former (nos)
Supply wedges(nos)
Supply Dead end Anchor block(nos)
Unit rate calculation for the post-tensioned slab and beams for 21mx27m
area for the live of 1.5 kN/m2
Supply and tieingTor bar 20mm Dia(Ton)
Supply and tieingTor bar 16mm Dia(Ton)
For Live load of 1.5kN/m2
Supply , Fixing and Removing
Formwork(m2) for Beam
Supply and placingConcrete Gr35(m3)
Supply and tieing Tor bar 25mm Dia(Ton)
Supply and tieingTor bar 10mm Dia(Ton)
Page 1 of 1
Appendix J- Basic Prices for Accessories for Post-Tensioned Slab
P a g e 1 o f 1
Basic Prices received from an Engineer who worked at the post -
tensioned slab construction site in Colombo.
1. 7-wire strand super grade –Nominal diameter 12.7 mm. (1840MP) 1 Ton Rs
150,000.00
2. Live end Anchor Block set for four strand holes with grouting pipe Rs -1700
each.
3. Wedges-Rs 120 each.
4. Recess former-Rs 280 .0 each plastic.
5. Duct/sheath for four number strands (19mm-50mm)- 5.5m long duct Rs 900
6. labours strength for erecting form work, fixing post tension cables and placing
concrete for a floor Fw - 25, PT works 12, Concrete 35.
7. Hydraulic Jack that was used in that project - two multi strand jacks. 20,000.0
each per month.
8. Did you use cement grouting or any other grouting to fill the sheath of
strands?? Ducts grouted after stressing using cement grout.
9. What is the cost to make a dead end anchorage? - Just make dead end
approximately Rs 1000.0
10. How many days were taken to complete a floor? 7 days cycle.
Appendix K-Work study spread sheet for three multi-storied buildings
ELEMENTS
Foundation 7,499,630.70 22% 6,673,239.00 10% 5,285,039.87 19%
Concrete 4,135,008.50 4,179,520.00 2,124,575.12
Reinforcement 3,043,207.20 2,067,616.00 2,553,362.36
Formwork 321,415.00 426,103.00 607,102.39
Beam 9,284,630.00 27% 19,512,586.20 31% 6,601,751.19 24%
Concrete 3,295,577.00 6,106,523.00 2,711,584.84
Reinforcement 4,631,628.00 9,441,403.20 3,189,758.75
Formwork 1,357,425.00 3,964,660.00 700,407.60
Slab 8,133,341.40 24% 21,951,555.50 34% 9,298,514.71 34%
Concrete 3,582,119.40 7,777,962.50 3,190,875.38
Reinforcement 3,440,174.00 8,386,828.00 5,224,750.12
Formwork 1,111,048.00 5,786,765.00 882,889.21
Shaft wall 2,211,592.25 6% 4,388,115.00 7% 1,602,413.46 6%
Concrete 1,264,844.25 2,501,225.55 913,375.67
Reinforcement 481,536.00 965,385.30 352,530.96
Formwork 465,212.00 921,504.15 336,506.83
Columns 6,962,848.45 20% 11,343,503.00 18% 4,776,854.47 17%
Concrete 1,306,169.25 2,423,772.00 1,035,862.97
Reinforcement 4,760,503.20 6,763,251.00 2,871,730.30
Formwork 896,176.00 2,156,480.00 869,261.20
(Beam + Slab)
cost per m2 7,207.31 6,379.10 6,697.02
HOSPITAL SHOPPING
ARCHADEOFFICE COMPLEX
Work study spread sheet for three multi-storied buildings
Page 1 of 1