1. Al-Quds Open University -Nablus
An-Najah National University
Faculty of Engineering
Civil Engineering Department
Prepared by:
Rana Adli Ramahi
Supervised by:
Eng. Imad Al-Qasim

2. Outline: Introduction Slabs preliminary design
Beams preliminary design
Three-dimensional structural modeling
Columns design
Walls design
Footings design
Stairs design
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3. Chapter One:
Introduction
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4. Project Description
The structure that designed is the building of Al-Quds Open University, Nablus-Palestine.
the land area is 3208 m2
It consists of two Buildings, Academic & Administrative Buildings.
They consists of five floors over ground & join together in two basement floors.
The ground floor elevation is 4.5 m, all other floors are 3.5m elevated.
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5. An-Najah National University

6. Project Description
The academic building will be designed in this project
It’s divided by structural joints with thicknesses equal 10cm roughly into four parts:
Part A is the central entrance for the academic building
Parts B & C consists of garages in the second basement floor, lectures rooms in floors (B1-F3), & offices in the fourth floor.
Part D is an auditorium (it’s design not completed)
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8. Philosophy of analysis & design
The structure was analyzed & designed by one & two dimensional structural models for the elements manually & using SAP, then using three dimensional structural model
SAP
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9. Design code & load combinations
The structural design was according to American concrete institute code (ACI318-08)
Depending on the used code the load combinations are:
U1 = 1.4D
U2 = 1.2D+1.6L+1.6H
U3 = 0.9D+1.6H
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10. Materials Soil Bearing Structural materials used in the design are:
concrete:
f’c=24 MPa for horizontal elements
f’c=28 MPa for vertical elements
Steel(both longitudinal & transverse):
fy=420 MPa
Soil Bearing
Bearing capacity of the soil is 400 KN/ m2
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11. Loads: Gravity loads: Live loads:
for all floors = 4 KN/m2 except the second basement floor which equal 5KN/m2
Dead Load:
In addition to own weight of the structural elements,
Superimposed dead load =4.36 KN/m2
Perimeter walls load
=20.6 KN/m ………………. for h=3.5m
=26.5 KN/m …………..…... for h=4.5m
Lateral loads: Only soil pressure was taken into consider.
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12. Structural Systems:
Part B & Part C are designed as one way ribbed slabs in X-direction, with hidden beams generally
Part A & Part D are designed as two way solid slabs with drop beams.
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13. Chapter Two:
Slabs Preliminary Design
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14. Thickness: For Part (B) & Part (C): One way ribbed slab L max = 5.8 m
Hmin=L / 18.5
= 5.8 / 18.5 = m
→Use h = 0.32 m
For Part (A) & Part (D):
Two way solid slab
Direct design method does not satisfied for this slab, so many trials for thicknesses done in the 3-d model to determine the suitable thickness.
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15. Loads estimation:
As a sample calculation Take the ribbed slab (rib1.1):
Own weight = 3.15 (KN/m) /0.55 = 5.73 KN/m2
Superimposed dead load =4.36 KN/m2
Total dead load = = 10.2 KN/m2
Live load = 4 KN/m2
→Wu (for rib) = 10.2 KN/m/rib
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16. Analysis using SAP:
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17. Reinforcement: φVc = φ*0.1667*√24*150*290 = 26.67 KN > Vu
No need for shear reinforcement
As min = *150*290 = 143 mm2
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18. Chapter Three:
Beams Preliminary Design
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19. Thickness: Take Beam B2 as a sample calculation:
All spans of this beam have a length 5.6 m
Hmin=L / 18.5 = 5.1 / 18.5 = 0.28 m
→Use hidden beams (h=32cm)
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20. Loads estimation: Wu from slab (5.7) =60.7 KN/m
Factored O.W. of beam = 0.32 * 1 * 25 *1.2 = 9.6 KN/m
Total ultimate load on beam =
= 100 KN/m
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21. Using ACI-coefficient the moment diagram(KN.m),shear diagram (KN):
As =ρ*b*d
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22. Torsion
From ribs models in SAP, the moments in the supports of the slab act on the beams as torsion ……..
Tm = KN.m/m
Tv(due to shear on the face of the beam from both sides)= KN.m/m
→Total factored torsion = KN.m/m (64.58 at d from face of support)
Reduction for compatibility torsion to be 47.5 KN.m/m
No equilibrium torsion occur because the center of the beam same as the center of columns carry it
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23. Torsion Check section adequacy for beam OK, Good section
Av/s +AT/s = 2.09 mm2/mm
Use 1φ12/100mm
Longitudinal steel at each support = 510 mm
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24. Total reinforcement (manual design)
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25. Model in SAP
The beam was modeled in SAP with fixed ends firstly & pin ends also, then the average of loaded was used for the design
Pin ended
fix ended
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26. Model in SAP The average moment (KN.m):
The total (torsion & flexure) longitudinal reinforcement:
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27. Section in beam B2
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28. Three Dimensional Structural Modeling
Chapter Four:
Three Dimensional Structural Modeling
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29. General
A three dimensional structural modeling done using SAP2000(v14.2.4)
Many verification checks must be achieved, serviceability, equilibrium, compatibility, & stress-strain relation ship.
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30. Serviceability Long Term Deflection Check
Take Part (C) & Part (B) as sample calculation, the check occurs for many spans, the critical one is the span between H-G&15-17
SAP information:
Mu=10.3 KN.m
∆D = , ∆D+L =
Calculations summery:
∆allowable = L/480 = 2.9/480 = m
∆LT = ∆L +α ∆D+α T ∆Ls = >∆all ,find Ig/Icr
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31. ∆LT = ∆L +α ∆D+α T ∆Ls = 0.001 < ∆all=0.006 OK
Ig = 7.03*104 cm4
Icr = 8277 cm4 .
∆L = ∆D - ∆D+L = mm
∆LT = ∆L +α ∆D+α T ∆Ls = < ∆all=0.006 OK
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32. Check Compatibility
From start animation in SAP, the compatibility(structure work as one unit) was verified
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33. Check Equilibrium Take Part (B) as sample calculation
Dead load (own weight)
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34. Dead load (Superimposed dead load)
Live load
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35. Error (own weight) = 2.4% OK Error in SID = 2.64% OK
Comparing results:
Error (own weight) = 2.4% OK
Error in SID = 2.64% OK
Error in live load = 0.33% OK
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36. Check stress-strain relationship
Take Part (B) as sample calculation, check for span 5-6 in beam B4 (1m*0.32m) & Wu =92 KN/m
+ve M = Wu*Ln2/16 = 92*3.92/16 = KN.m
-ve M =127.2 KN.m at each support & avg is 127.2KN.m
1-D model: (+ve M) + [(–ve MR + -ve ML)/2] = KN.m
3-D model: M = 233 KN.m
Error = 8.7………………….. OK
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37. Slab Design
Take Part (B) as sample calculation, design slab thickness 32cm (ribbed slab R1) & cover 3cm.
Bending moment diagram for rib 1 (KN.m/m)
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39. Beam Design
Take Part (B) as sample calculation, design beam on grid (F)
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41. Chapter Five:
Columns Design
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42. Preliminary Design Take group G2 as sample Pu = 2000 KN ,
assume ρ = 0.01
Pu = 0.65 * 0.8 * [0.85* f’c *(0.99Ag) + Fy*(0.01Ag)]
→ Ag = m2 ,
use section b*h = 0.5 m *0.5 m
As = ρ * Ag = 0.01 *0.25 = 2.5*10-3 m2 = 2500 cm2
So, use 8φ20 mm
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43. (3-D)Design
Take group G2 as sample( Pu = KN & M2=47 KN.m &M1=29.66 KN.m), design for axial, flexure & shear
Check buckling, depend on stiffness's of column & related beams:
K factor =0.82 (Non-sway)
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44. 34 – 12(M1/M2) >22.96 (neglect slenderness)
K*Lu/r = 0.82*4.2/0.15 = 22.96
Check slenderness:
34 – 12(M1/M2) >22.96 (neglect slenderness)
δns = 0.92, use δns = 1 →Md=Mu = 47 KN.m
Using interaction diagram(f’c=28, fy=420, ƴ=0.75)
→ρ=0.015, As=30 cm2 → Use 8φ22 mm
Use φ10/200 mm
Vn<Vc/2 …………… no shear reinforcement
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45. Chapter Six:
Walls Design
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46. Bearing wall design Take wall 6as sample, design for axial loads.
average axial load=337 KN
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47. Section used has a thickness =25 cm = 1952KN > Pu OK
Reinforcement (minimum)
Vertical reinforcement = *Ag (Use 1φ10/300 mm)
Horizontal reinforcement = 0.002*Ag (Use 1φ10/300 mm)
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48. Basement wall design
Take wall 11 as sample, design for axial loads & soil load.
Vu (from sap) = 122 KN
φVc = 127KN>Vu OK
From SAP:
Vertical Moments:
M +ve max = 55 KN.m/m (ρ=0.004) → (1φ14/250mm)
M-ve max = 30 KN.m/m (ρ=0.0033) → (1φ14/250mm)
 Horizontal Moments:
M +ve max = 33 KN.m/m (ρ=0.003) → (1φ12/300mm)
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49. Chapter Seven:
Footings Design
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50. Footing system
Footings that used in this project can be classified into three types:
Wall footing
Single footing
Combined footing
No need for using mat foundation because the soil has high bearing capacity.
The footings was grouped into 27 group, depending on the column load, dimension, shape, adjacency.
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51. Single footing (G22) Footing area=Pa/Qall →B= 2.5m & L= 2.6m
Footing thickness designed to resist the wide beam & Punching shear: φVc > Vu & φVcp > Vup
Flexure design: Mu = qu*l2/2
In B direction:
M= 411 KN.m → 7φ20/m
In L direction:
M= 197 KN.m →5φ18/m
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52. Single footing (G22)
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53. Chapter Eight:
Stairs Design
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54. The stair was designed manually & using SAP:
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55. Thank You
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