Explains in detail about the planning and designing of a G + 2 school building both manually and using software (STAAD Pro). With the reference with this we could design a building of a school with 2 blocks and G + 2 building.

1. DESIGN
OF

2. PROJECT MEMBERS
RAGHAV .S: 2013101073
TAMIL SELVAM .D : 2013101321
UDHAYA KUMAR .K : 2013101324
B 19

3. OBJECTIVE :
To analyze the main structural components: Slab,
Beam, Column, Footing manually and to validate
the same by Staad Pro Software
 NEEDS :
To improve higher education schools in
newly developing areas.
Location: near Vallalapatti ,ALAGAR KOVIL
SOFTWARE : AUTOCADD, STAAD PRO

4. Specification
 LOCATION : VALLALAPATTI
 TYPE OF SOIL : RED SOIL
 TYPE OF FOOTING : ISOLATED
FOOTING
 No. Of Storey : G + 2
REFERENCE
To design SCHOOL BUILDING we referred IS 456 –
2000, SP 16 and IS 875 PART 2 (SCHOOL BUILDING)

14. TOP VIEW

15. ISOMETRIC VIEW

16. PRISMATIC VIEW

17. AXIAL FORCE DIAGRAM

18. SHEAR -Y DIAGRAM

19. SHEAR -Z DIAGRAM

20. TORSION DIAGRAM

21. BENDING -Y DIAGRAM

22. BENDING-Z DIAGRAM

23. BEAM STRESS DIAGRAM

24. DESIGN OF SLAB
DATA’S:-
Slab size=9.0mx7.5m
Materials:M25,Fe415
1.CALCULATION OF OVERALL DEPTH:
ly/lx=9/7.5=1.2>2
For two way continuous slab,
Span/Effective depth =32
7500/32=234.37mm
deff=235mm
D = 235+25
=260mm
2.LOAD CALCULATION:
self weight of slab = 0.15 x 25=3.75 KN/m^2
floor finish =0.75 KN/m^2
Total load=4.5KN/m^2

25. 2.LOAD CALCULATION:
self weight of slab = 0.15 x 25=3.75 KN/m^2
floor finish =0.75 KN/m^2
Total load=4.5KN/m^2
3.MOMENT CALCULATION:
consider I m strip
W = Wd + Wl
=4.5 + 2 = 6.5
Wu=1.5 x W
= 1.5 x 6.5 = 9.75 KN/m

26. Step 5 : boundary condition (one short edge continuous)
x=0.08
alpha y=0.059
Mux=ax w lx^2
=0.08 x 9.75 x 7500^2
=43.875KNm
Muy=ay w lx^2
= 0.059 x 9.75 x 7500^2
= 32.35 KNm
Mu lim =0.13 fck b d^2
=0.133 x 25 x 1000 x 235^2
= 183.62 KNm
Mux < Mu lim
Muy < Mulim

27. STEP 6 : SHORTER SPAN
Mux = 0.87 x fy x Ast x (135- ((0.42(0.87 x fy x Asty)/
(0.36 x fck b)
44x10^6 = 361.05xAstx(135-(151.64Astx/7200))
= 1265.25mm^2
Assume 12mm dia bar
Spacing = 1000(3.14x12^2)/1265.25
=100mm spacing
Step7: Longer span
32.35x10^6= 0.87x415xAstx(135-
0.42(.87x415xAsty/(0.36x25x1000))
=809.46mm^2
Assume 12mm dia bar
Spacing = 1000(3.14x12^2)/809.46
=140mm spacing Spacing

28. Step8: Minimum Ast:
0.12% of c/s
=(0.12/100)x1000x235
=282mm^2
Assume 10mm dia bar
Spacing = 1000(3.14x10^2)/282
=280mm spacing
RESULT:
Ast min = 10mm dia bars @280mm c/c
Ast = 12mm dia bars @100mm c/c (Shorter)
Ast = 12mm dia bars @140mm c/c(Longer)

29. STAAD output -BEAM

30. Design of beam
DATA’S:
Breadth = 300mm
Depth = 400mm
Beam Number = 449
Span = 4.6m
Ultimate shear = 85.03KN
Ultimate moment = 630.326KNm
fck = 25N/mm²
fy = 415N/mm²
1.DIMENSIONS:
Cover depth,d´ = 50mm
Effective depth,d = D - d´
= 400 - 50
= 350mm
Therefore,Effective depth = 350mm

31. Mu(lim) = 0.138 fck b d²
= 0.138x25x300x350²
= 540KN.m
Since Mu< Mu(lim) then doubly reinforced
Step2 ;
to find Asc= (Mu- Mulim)/fsc * fy
= (90.3x10^6)/361 x 415
=603.18 mm^2
adopt 16 mm dia bars 3 nos @compression zone
Ast2 = (603.18 x 361)/0.87 x 415
=603.18 mm ^2
Ast1 = 0.36 x fck x b * Xu lim / (0.87 x fy )
= (0.36 x 25 x300 x0.48 x 350)/(0.87 x 415)
= 1246.2 mm^2
Ast = Ast 1+ Ast 1= 1851.3 mm^2
adopt 25 dia bars 4 nos

32. STAAD output- COLUMN

33. DESIGN OF COLUMN
DATA’S:
Breadth = 300mm
Depth =600 mm
Ultimate load = 1093.79 KN
Ultimate moment at x-axis = 1.34 KNm
Ultimate moment at y-axis = 77.12 KNm
fck = 25 N/mm²
fy = 415 N/mm²
Size of column : 300 mm X 600 mm
1. DIMENSIONS:
Cover depth,d´ = 62.5 mm
Effective depth,d = D - d´ = 600-62.5 = 537.5 mm
Therefore,Effective depth = 537.5mm

34. 2. LONGITUDINAL REINFORCEMENT:
Assume P =2.8 %
Moment capacity at x-x axis:
Pu/fck b D=0.24
Assume 62.5 mm cover & 25mm Ø bars.
d’=50+25/2=62.5 mm
d’/D=62.5/600=0.08
Refer SP:16 Chart-44
Mux1/fck b D^2
Mux1=216 KN/m
Moment capacity at y-y axis:
d’/D= 0.15
Refer SP:16 Chart-45
Muy1/fck b D^2
Muy1=360 kNm

35. Puz=0.45 fck Ac+0.75 fy Asc
p=100Asc/bD
Asc=5101mm^2
Ag=Ac+Asc
Ac=Ag-Asc
=5101 – (300 x 600)
=174899 mm^2
Puz= 2.283 x 10^6
Pu/Puz=0.47
Take αn=0.1
[Mux/Mux1]+[Muy/Muy1]<1
0.22<1
Hence,safe.
Assume,25mmØ bars.
asc=490.8 mm^2
Number of bars=Asc/asc=10 nos

36. Spacing=1000xast/Ast
=1000x490.8/5101
=96.2 mm
Provide 8mm Ø @90mm c/c spacing.

37. FOUNDATION
• FOUNDATION Dimensions
• shape : Rectangular
• Length : 0.7m
• Width : 0.3m

38. Input Values
Footing Geomtery
Design Type :Calculate Dimension
Footing Thickness (Ft) :305.000 mm
Footing Length - X (Fl) :1000.000 mm
Footing Width - Z (Fw) :1000.000 mm

39. Unit Weight of Concrete : 25 kN/m3
Strength of Concrete : 25 N/mm2
Yield Strength of Steel : 415 N/mm2
Minimum Bar Size : Ø6
Maximum Bar Size : Ø32
Minimum Bar Spacing : 50 mm
Maximum Bar Spacing : 500 mm
Footing Clear Cover : 50 mm

40. Soil Properties
Soil Type : Drained
Unit Weight : 22.000 kN/m3
Soil Bearing Capacity : 100.000 kN/m2
Sliding and Overturning
Coefficient of Friction : 0.5
Factor of Safety Against Sliding :1.5
Factor of Safety Against Overturning :1.5

41. Final Footing Size
Length (L2) = 4.850m
Width (W2) = 4.850m
Depth (D2) = 0.509 m
Area (A2) = 23.523m2

42. Pressures at Four Corner

43. Design of staircase
DOG-LEGGED STAIRCASE WAIST SLAB TYPE
DATA’S:
Height b/w the floors=3 m
Tread=270 mm
Rise=160mm
Landing width=1.25m
Live load=5KN/m^2
Floor finishing=0.6 to 1 KN/m^2
Wall thickness=230mm
Materials:M25 & Fe415
1.DIMENSIONS:
R=160mm;T=270mm
B-[(160^1/2)+(270^1/2)]^1/2
= 314 mm
Number of steps=3/0.16=18 steps

44. In case of dog-legged staircase,9 number of steps for
1st flight & other 9 number of steps for 2nd flight.
Effective span=0.23/2+1.25+(8 x 0.27)+1.25+0.23/2=
4.68 m
Waist slab thickness=Leff/20=234 mm
Assume cover 20mm & 12 mmØ bars.
deff(landing)=234-20-12/2=208mm
2.LOAD CALCULATION:
Dead load of slab on slope = Ws = (0.234 x 1 x 25 )=
5.85 KN/m
Dead load of slab on horizontal span
W = Ws ( R^2 + T ^2)^1/2/T
W = 0.80 KN/m

45. Dead loads on one step = 0.5 x 0.16 x 0.27 x 25 = 0.54
KN/m
Loads of steps per metre length = 0.54 x 1000/ 270 = 2
KN/m
Floor Finish = 0.6 KN/m
Total Dead load = 6.8 + 2 +0.6 = 9.4 KN/m
Service live load = 5 KN/m^2
Total service load = 14.4 KN/m
Factored Load = Wl = (1.5 x
14.4 ) = 22 KN/m
3.MOMENT CALCULATION:-
M = 0.125 Wl^2
= 0.125 x 22 x 4.68 x 4.68 = 60.23 K

46. 4. Check for depth of waist slab:-
d = (Mu /0.138 fck b)^1/2
= 147.72 < 208 mm
Hence Safe
5. Main Reinforcement:-
Mu = (0.87 fy Ast d ) ( 1- Astfy /bd fck)
= 879.102 mm
6. Provide 12 mm dia at 200 mm
c/cDistrubution Reinforcement:-
= 0.12 per cent cross section
= 0.0012 x 1000 x 234
= 280.8 mm^2/m
Provide 10 mm dia bars @ 300 c/c

47. REINFORCEMENT DETAILS:-
Nominal reinforcement 12mmØbars @ 200mm c/c spacing is
provided in the landing slab near the support at the top.
To resist BM & also provide 10mmØbars @ 300mm c/c spacing as
distribution bars.

48. APPROXIMATE ESTIMATE :
Total Area = 29457.68 m2
Building Area = 12996.8 m2
Construction cost per m2 = Rs.15,000/-
Estimated cost = Rs.15,000 x
12996.8
= Rs.19,49,52,000/-
(For a floor)
For G+2 school building,
Total Estimated cost = Rs.19,49,52,000 x 3
= Rs.58,45,56,000

49. T H A N K Y O U