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Civil & Environmental Engineering Department
First semester -Term (131)
CE 315 – Reinforced Concrete
Term project
Analyses and Design of a Two-Storied RC Building
Instructors: Dr.Mohammed Baluch
Dr.Mohammed Al-Osta
Prepped by: Mohammed Jamal Sandougah
ID# 200816060
Email: eng-kovo@hotmail.com
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Table of Contents
1. Introduction...........................................................................................................................................4
2. Project Objectives and scope of work...................................................................................................4
2.1. Description of Structure................................................................................................................5
2.2. Loads Calculation .........................................................................................................................7
2.2.1. Slab Loads.............................................................................................................................7
2.3. Building Geometry......................................................................................................................11
2.3.1. Modeling Stages..................................................................................................................11
2.3.2. Normal Structure.................................................................................................................11
2.3.3. Full Structure Modeling......................................................................................................14
2.4. Loads Assigned...........................................................................................................................15
2.5. Ribbed Slab Design.....................................................................................................................17
2.6. Beam Design...............................................................................................................................20
2.7. Column Design ...........................................................................................................................25
2.8. Foundation Design......................................................................................................................28
2.8.1. Procedure ............................................................................................................................28
2.8.2. Results.................................................................................................................................30
Conclusion ..................................................................................................................................................67
References...................................................................................................................................................68
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List of Figures
Figure 2-1: Side View of the Building ..........................................................................................................5
Figure 2-2: Top View of the Building ..........................................................................................................6
Figure 2-3: Top View of the Building with Direction of Load.....................................................................7
Figure 2-4: Minimum Thickness for One-Way Solid and Ribbed Slabs......................................................8
Figure 2-5: Block Dimensions......................................................................................................................9
Figure 2-6: Ribbed Slab Dimensions ......................................................................................................10
Figure 2-7-1: Normal Structure (Front view) .............................................................................................11
Figure 2-7-2: Normal Structure (Side view)...............................................................................................12
Figure 2-8: Normal Structure (Top view)...................................................................................................13
Figure 2-9: Full Structure (3D Model).......................................................................................................12
Figure 2-10: Load on Grade Beams............................................................................................................13
Figure 2-11: Load on Parapet......................................................................................................................16
Figure 2-12: ACI Coefficients Conditions..................................................................................................17
Figure 2-13 : ACI Moment Coefficients (1)...............................................................................................18
Figure 2-14: ACI Moment Coefficients (2) ................................................................................................19
Figure 2-16: Critical Beam .........................................................................................................................20
Figure 2-17: Moment diagrom of beam#200..............................................................................................21
Figure 2-18: Steel arrangement of beam#200 (1) .......................................................................................21
Figure 2-19: Steel arrangement of beam#200 (2) .......................................................................................22
Figure 2-20: Shear Diagram for beam #200 ...............................................................................................23
Figure 2-21: Specifications of shear reinforcement of beam #200.............................................................24
Figure 2-22: Critical Column #127.............................................................................................................25
Figure 2-23: Output of column#127 ...........................................................................................................26
Figure 2-24: Footings distribution of Solid Slab Structure.........................................................................28
Figure 2-25: Concrete and Rebar Parameters .............................................................................................28
Figure 2-26: Cover and soil parameters......................................................................................................29
Figure 2-27: Footing geometry parameters.................................................................................................29
Figure 2-28: Typical elevation section of footing.......................................................................................30
Figure 2-29: Typical plan section of footing ..............................................................................................30
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1. Introduction
The design of the Two-story reinforced concrete structure entailed a number of steps
and calculations. Each section listed below describes one step in the process of the design.
Attached to the end of this report are sample hand calculations for each step in the design
process.
2. Project Objectives and scope of work
The main objectives revolved around the application of the theoretical background in
reinforced concrete design courses to design a full structure instead of elements (beam,
column, foundation and slab). Another objective of this project is to learn how to utilize the
AutoCAD drawing software and the (STAAD.Pro) software tools in the best manner which
would be time saving and practical in modeling, analyzing and designing the structure.
Moreover, the project would help the group in interpreting the architectural drawings of the
building which would be useful in future careers.
On the managerial side, the group will conduct cost estimations and comparisons study for all
alternatives which would help to improve the decision-making process and the quantity
surveying skills. In addition, the project will help the group in improving time-management
skills.
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2.1. Description of Structure
Building comprises of two story reinforced concrete structure. Basic building dimensions
are as follows:
Building footprint: 13.5 m x 13.5 m.
Building height: Building height: 9.6 m.
STADD side and top view drawings of the Building are shown in Figure and Figure 2-2.
Figure 2-1: Said View
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2.2. Loads Calculation
2.2.1. Slab Loads
a) Slab self weight
Since the ratio of long edge to the short edge of slab =
𝟓
𝟓
= 𝟏 𝐚𝐥𝐬𝐨
𝟑.𝟓
𝟓
= 0.7 the load will
transfer in the short direction as shown in Figure 2-3 and the design will assumed as one way
solid slab and the hidden square as flour slab.
Figure 2-3: Top View of the Building with Direction of Load
UP
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Minimum slab depth:
Following ACI-318-08 the minimum thickness for one-way solid slabs as shown in Figure 2-4
is
𝑙
24
for one end continuous and
𝑙
28
for both ends continuous.
Figure 2-4: Minimum Thickness for One-Way Solid and Ribbed Slabs
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One end continuous
𝑙
24
=
5000
24
= 208.33 𝑚𝑚
Both ends continuous
𝑙
28
=
5000
28
= 178.57 𝑚𝑚
Weight of Block:
No. of rib/m =
1
0.5
= 2 ribs
No. of blocks/𝑚2
= 2 × 5 = 10
The weight of blocks in one meter square of ribbed slab =
(Number of blocks) × (weight of one block) × (9.81)
Weight of blocks/𝑚2
= 10 × 12 ×
9.81
1000
= 1.2
kN
𝑚2
Weight of ribs:
Each one meter of ribbed slab has two ribs as shown in Figure 2-6.
Weigh of 𝑟𝑖𝑏 = (width(b) × depth(d) × number of ribs) × (density of concrete) ×
(length)
Weight of ribs/𝑚2
= 2 × 0.1 × 0.2 × 25 = 1
kN
𝑚2
Figure 2-5: Block Dimensions
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Weight of top slab (t):
Top slab weight = (minimum thickness – depth of rib (d)) × (density of concrete) × (length)
Weight of toping slab/m2 = 0.07 × 25 = 1.75
kN
𝑚2
Self weight of the ribbed slab:
Self weight = (Weight of Block) + ( weight of rips) + ( Top mat weight)
Self Weight of ribbed slab = 1 + 1.2 + 1.75 = 3.95
kN
𝑚2
Figure 2-6: Ribbed Slab Dimensions
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2.3. Building Geometry
According to the Architectural drawings, the building is mainly composed of a 13.5 m X
13.5 m rooms with main beams spanning over 5, 3.5 and 3 meters with a center-to-center of
column spacing of 5 and 3.5 meters. In addition, the building includes a rectangular bathroom
with a thickness of 0.15 meters and with area of10.5 𝑚2.
2.3.1. Modeling Stages
1. Draw the normal structure using STAAD.Pro software
2. Define section properties of the structure (columns, beams and slab)
2.3.2. Normal Structure
Front view dimensions of the two structures are shown in Figure 2-7-1.
Figure 2-7-1: Normal Structure (Front view)
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Side view dimensions of the two structures are shown in Figure 2-7-2.
Figure 2-7-2: Normal Structure (Side view)
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Top view dimensions are shown in Figure 2-8 .
Figure 2-8: Normal Structure (Top view)
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2.3.3. Full Structure Modeling
3D of the structure is shown in Figure 2-9.
Figure 2-9: Full Structure (3D Model)
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2.4. Loads Assigned
Dead load on grade beam is 17.375
𝐾𝑁
𝑚
as shown in Figure 2-10.
Figure 2-10: Load on Grade Beams
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Dead load on parapet is 12.2
𝐾𝑁
𝑚
as shown in Figure 2-11.
Figure 2-11: Load on Parapet
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2.5. Ribbed Slab Design
Using ACI-318-08 chapter 8.3.3, Check the ACI limits which is shown in Figure 2-12.
Figure 2-12: ACI Coefficients Conditions
All conditions are satisfied.
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Figure 2-13: ACI Moment Coefficients (1)
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−
𝑊𝑢 𝑙𝑛2
24
+
𝑊𝑢 𝑙𝑛2
14
−
𝑊𝑢 𝑙𝑛2
10
−
𝑊𝑢 𝑙𝑛2
11
+
𝑊𝑢 𝑙𝑛2
16
−
𝑊𝑢 𝑙𝑛2
11
Figure 2-15: ACI Moment Coefficients (2)
𝑊𝑢 = 1.2(𝐷𝐿) + 1.6(𝐿𝐿)
𝑊𝑢 = 1.2(6.95) + 1.6(2.5) = 12.34
𝐾𝑁
𝑚
Apply moment coefficients which are shown in Figure 2-15:
Equations used for calculations [1]:
1) 𝑀 𝑢 = 𝑚𝑜𝑚𝑒𝑛𝑡 𝑓𝑎𝑐𝑡𝑜𝑟 × 𝑊𝑢 × 𝑙 𝑛
2
2) 𝑅 𝑛 =
𝑀 𝑢
∅𝑏𝑑2
3) 𝑚 =
𝑓𝑦
0.85𝑓′ 𝑐
4) 𝜌 =
1
𝑚
(1 − √1 −
2𝑚𝑅 𝑛
𝑓𝑦
)
5) 𝜌min =
3 ×√𝑓𝑐′
𝑓𝑦
but not less than
200
𝑓𝑦
6) 𝐴 𝑠 = 𝜌𝑏𝑑
𝑊𝑛 12.34 KN/m 𝑏 0.3048 m
𝑙 𝑛 5,3.5 m 𝑑 0.27 m
𝑓′ 𝑐 40 MPa
𝑓𝑦 420 MPa
𝑀 𝑢 -12.85 22.035 -30.85 -13.75 9.45 KN-m
𝑅 𝑛 -642.567 1101.864 -1542.65982 -687.571 472.5489 KN/m2
𝑚 12.35294 12.35294 12.35294 12.35294 12.35294 -
𝜌 0.001546 0.002667 0.003760 0.0016539 0.001133 -
𝜌 𝑚𝑖𝑛 0.00142857 0.00142857 0.00142857 0.00142857 0.00142857 -
𝐴 𝑠 127.229616 219.5190 309.4606 136.1094 117.5656 𝑚𝑚2
Bar #4 1 2 3 2 1
5.0 m 3.5 m
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2.6. Beam Design
Critical beam found to be beam # 200 as shown in Figure 2-16.
Figure 2-16: Critical Beam
Checking the design of beam # 200
For main re-bars
Take cover = 0.04 𝑚 , ℎ = 0.5 𝑚 , 𝑏 = 0.2 𝑚 , 𝑑 = 0.46 𝑚
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From STAAD.pro analysis, max (-ve) moment
𝑀 𝑢 = −33.6𝐾𝑁. 𝑚 , 𝐴 𝑠 = 3 ×
𝜋
4
× 122
= 339.3 𝑚𝑚2
Max (+ve) moment
𝑀 𝑢 = 10.6 𝐾𝑁. 𝑚 , 𝐴 𝑠 = 3 ×
𝜋
4
× 122
= 339.3 𝑚𝑚2
As Shown in Figure .
Figure 2-17: Moment diagram of beam #200
Moment diagram of beam #200
Figure 2-18: Steel arrangement of beam#200 (1)
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Check (-ve) moment:
∅𝑀 𝑛− = 0.9(64.059 ) = 57.65 > 33.6 𝐾𝑁. 𝑚 OK
Check (+ve) moment:
∅𝑀 𝑛+ = 0.9(64.059 ) = 57.65 > 10.6 𝐾𝑁. 𝑚 OK
For Stirrups:
From STAAD.pro analysis and design the values of Vu, Vc and Vs as well as specifications of
shear reinforcement is shown below in Figure and Figure .
Figure 2-20: Shear Diagram for beam #200
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Figure 2-21: Specifications of shear reinforcement of beam #200
Check:
∅𝑉𝑛 = 𝑉𝑠 + 𝑉𝑐 = 0 + 98.7 = (0.75) × 98.7 = 74.03 𝐾𝑁
∅𝑉𝑛 ≥ 𝑉𝑢 → 74.03 ≥ 27.62 OK
∅𝑉𝑐
2
> 𝑉𝑢 → 37.01 > 27.62 OK
So, no need for stirrups.
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2.7. Column Design
Critical Column found to be beam # 127 as shown in Figure .
Figure 2-22: Critical Column #127
The column output given by STAAD.pro for column # 127 is shown in the
following table and Figure .
SI Unit English Unit
𝑃𝑢 18.03 𝐾𝑁 4.1 𝐾𝑖𝑝
𝑀𝑧 125.14 𝐾𝑁. 𝑚 1107.6 𝐾𝑖𝑝. 𝑖𝑛
𝑀 𝑦 11.96 𝐾𝑁. 𝑚 105.9 𝐾𝑖𝑝. 𝑖𝑛 𝑏 13.78 𝑖𝑛
𝐴 𝑔 0.263 𝑚2
407.7 𝑖𝑛2 𝑑 29.5 𝑖𝑛
𝐴 𝑠 3176 𝑚𝑚2
4.923 𝑖𝑛2
𝑓′ 𝑐 40 𝑀𝑝𝑎 5.8 𝐾𝑠𝑖
𝑓𝑦 420 𝑀𝑝𝑎 60.9 𝐾𝑠𝑖
𝑐𝑜𝑣𝑒𝑟 0.04 𝑚 1.57 𝑖𝑛
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Figure 2-23: Output of column#127
To check the column reinforcement, checking whether the column is short or long should be
done first. If the column is long the effect of slenderness should be taken in consideration, if
not, no need to consider the effects of slenderness.
Slendernen ratio→
𝑘𝑙 𝑢
𝑟
Check:
Since the structure is braced frame if
𝑘𝑙 𝑢
𝑟
≤ 34 − 12
𝑀1
𝑀2
it is short column, otherwise it is
long column.
34 − 12
𝑀1
𝑀2
= 34 − 12
11.96
125.14
= 32.85
Since the column both fixed ends 𝑘 = 1
𝑙 𝑢 = 3.5 𝑚
𝑟 = √
𝐼
𝐴
= √
𝑏ℎ3
12𝑏ℎ
= √
0.750 × 0.3503
12(0.750)(0.350)
= 0.101 𝑚𝑚
𝑘𝑙 𝑢
𝑟
=
1(3.5)
0.101
= 34.7 > 33.73, so it is long column.
𝛾 =
ℎ − 2 × 𝑐𝑜𝑣.
ℎ
=
13.78 − 2 × 1.57
13.78
= 0.77
Since that the column has biaxial moments acting on it, the equivalent eccentricity method
will be applied.
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2.8. Foundation Design
Foundations design was done using STAAD.foundation software.
2.8.1. Procedure
1) Analyze the structure using STAAD.pro.
2) Import STAAD.pro file into STAAD.foundation. Figure shows the distribution
of isolated footings.
Figure 2-24: Footings distribution of Solid Slab Structure
3) Define concrete and rebar parameters as shown in Figure :
Figure 2-25: Concrete and Rebar Parameters
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4) Define cover and soil parameters as shown in Figure 2-26:
Figure 2-26: Cover and soil parameters
5) Define footing geometry parameters as shown in Figure :
Figure 2-27: Footing geometry parameters
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2.8.2. Results
Below are two tables of footings sizes and reinforcement. Typical steel arrangement
and footing sizes are shown in Figure 2-28 and Figure 2-29.
Figure 2-28: Typical elevation section of footing
Figure 2-29: Typical plan section of footing
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Foundation geometry for shear wall
Isolated Footing 21
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Input Values
Footing Geomtery
Footing Thickness (Ft) : 500.00 mm
Footing Length - X (Fl) : 1000.00 mm
Footing Width - Z (Fw) : 1000.00 mm
Eccentricity along X (Oxd) : 0.00 mm
Eccentricity along Z (Ozd) : 0.00 mm
Column Dimensions
Column
Shape :
Rectangular
Column
Length - X
(Pl) :
0.75 m
Column
Width - Z
(Pw) :
0.35 m
Pedestal
Include
Pedestal?
No
Pedestal
Shape :
N/A
Pedestal
Height (Ph) :
N/A
Pedestal
Length - X
(Pl) :
N/A
Pedestal
Width - Z
(Pw) :
N/A
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Design Parameters
Concrete and Rebar Properties
Unit Weight of Concrete : 25.000 kN/m3
Strength of Concrete : 25.000 N/mm2
Yield Strength of Steel : 415.000 N/mm2
Minimum Bar Size : # 6
Maximum Bar Size : # 40
Minimum Bar Spacing : 50.00 mm
Maximum Bar Spacing : 500.00 mm
Pedestal Clear Cover (P, CL) : 50.00 mm
Footing Clear Cover (F, CL) : 50.00 mm
Soil Properties
Soil Type : UnDrained
Unit Weight : 22.00 kN/m3
Soil Bearing Capacity : 200.00 kN/m2
Soil Surcharge : 0.00 kN/m2
Depth of Soil above Footing : 0.00 mm
Undrained Shear Strength : 0.00 N/mm2
Sliding and Overturning
Coefficient of Friction : 0.50
Factor of Safety Against Sliding : 1.50
Factor of Safety Against Overturning : 1.50
------------------------------------------------------
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Applied Loads - Strength Level
LC
Axial
(kN)
Shear X
(kN)
Shear Z
(kN)
Moment X
(kNm)
Moment Z
(kNm)
5 74.877 99.102 5.015 1.482 -348.409
6 -279.122 -0.531 137.333 17.802 0.941
7 -67.530 -185.540 -5.085 -1.439 488.882
8 281.613 0.436 -82.371 -13.372 -0.766
9 203.757 -6.409 -1.239 2.688 6.289
10 16.648 -2.920 -0.046 0.267 2.133
11 285.260 -8.973 -1.735 3.763 8.804
12 271.146 -12.363 -1.561 3.654 10.959
13 261.157 -10.611 -1.533 3.493 9.679
14 304.410 71.590 2.525 4.412 -271.181
15 21.211 -8.116 108.379 17.467 8.299
16 190.484 -156.123 -5.555 2.075 398.652
17 469.799 -7.343 -67.384 -7.472 6.934
18 380.960 147.952 6.491 5.865 -547.775
19 -185.438 -11.461 218.200 31.977 11.185
20 153.108 -307.475 -9.669 1.191 791.890
21 711.737 -9.914 -133.327 -17.902 8.455
22 261.157 -10.611 -1.533 3.493 9.679
23 261.157 -10.611 -1.533 3.493 9.679
24 261.157 -10.611 -1.533 3.493 9.679
25 261.157 -10.611 -1.533 3.493 9.679
26 303.185 152.795 6.909 4.791 -551.795
27 -263.213 -6.618 218.618 30.903 7.166
28 75.333 -302.632 -9.251 0.117 787.871
29 633.962 -5.072 -132.909 -18.976 4.435
30 183.381 -5.768 -1.115 2.419 5.660
31 183.381 -5.768 -1.115 2.419 5.660
32 183.381 -5.768 -1.115 2.419 5.660
33 183.381 -5.768 -1.115 2.419 5.660
Reduction of force due to buoyancy = -0.00 kN
Effect due to adhesion = 0.00 kN
Min. area required from bearing pressure, Amin = P / qmax = 3.621 m2
Area from initial length and width, Ao = Lo * Wo = 1.00 m2
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Final Footing Size
Length (L2) = 8.60 m Governing Load Case : # 28
Width (W2) = 8.60 m Governing Load Case : # 28
Depth (D2) = 0.50 m Governing Load Case : # 28
Area (A2) = 73.96 m2
Pressures at Four Corners
Load Case
Pressure at
corner 1
(q1)
(kN/m^2)
Pressure at
corner 2
(q2)
(kN/m^2)
Pressure at
corner 3
(q3)
(kN/m^2)
Pressure at
corner 4
(q4)
(kN/m^2)
Area of footing
in uplift (Au)
(m2
)
20 23.4557 5.6150 5.6837 23.5244 -0.0000
21 21.4516 21.1986 22.7940 23.0471 -0.0000
21 21.4516 21.1986 22.7940 23.0471 -0.0000
18 23.4297 11.6994 11.8712 23.6015 -0.0000
If Au is zero, there is no uplift and no pressure adjustment is necessary. Otherwise,
to account for uplift, areas of negative pressure will be set to zero and the pressure
will be redistributed to remaining corners.
Summary of Adjusted Pressures at 4 corners Four Corners
Load Case
Pressure at
corner 1 (q1)
(kN/m^2)
Pressure at
corner 2 (q2)
(kN/m^2)
Pressure at
corner 3 (q3)
(kN/m^2)
Pressure at
corner 4 (q4)
(kN/m^2)
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20 23.4557 5.6150 5.6837 23.5244
21 21.4516 21.1986 22.7940 23.0471
21 21.4516 21.1986 22.7940 23.0471
18 23.4297 11.6994 11.8712 23.6015
Adjust footing size if necessary.
Check for stability against overturning and sliding
- Factor of safety against sliding Factor of safety against overturning
Load Case
No.
Along X-
Direction
Along Z-
Direction
About X-
Direction
About Z-
Direction
5 5.042 99.634 1077.012 10.798
6 607.904 2.350 32.092 2299.745
7 2.309 84.264 925.514 6.335
8 1384.520 7.321 95.058 5274.047
9 88.014 455.234 2345.246 511.025
10 161.146 10206.828 16563.146 1126.246
11 67.409 348.657 1796.190 391.387
12 48.353 383.021 1789.319 299.929
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13 55.866 386.674 1869.768 340.213
14 8.583 243.336 931.256 17.213
15 58.261 4.363 56.748 329.068
16 3.571 100.358 6821.752 10.057
17 94.942 10.346 145.646 565.310
18 4.412 100.556 616.140 9.028
19 32.242 1.693 22.525 187.861
20 1.752 55.724 1271.710 4.900
21 82.517 6.136 83.198 524.584
22 55.866 386.674 1869.768 340.213
23 55.866 386.674 1869.768 340.213
24 55.866 386.674 1869.768 340.213
25 55.866 386.674 1869.768 340.213
26 4.017 88.846 640.209 8.403
27 49.961 1.512 20.279 271.454
28 1.652 54.037 953.567 4.577
29 153.646 5.863 78.441 961.341
30 96.027 496.681 2558.767 557.551
31 96.027 496.681 2558.767 557.551
32 96.027 496.681 2558.767 557.551
33 96.027 496.681 2558.767 557.551
Critical Load Case And The Governing Factor Of Safety For Overturning And
Sliding - X Direction
Critical Load Case for Sliding along X-Direction : 28
Governing Disturbing Force : -302.632 kN
Governing Restoring Force : 499.900 kN
Minimum Sliding Ratio for the Critical Load Case : 1.652
Critical Load Case for Overturning about X-Direction : 27
Governing Overturning Moment : 140.210 kNm
Governing Resisting Moment : 2843.342 kNm
Minimum Overturning Ratio for the Critical Load Case : 20.279
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Critical Load Case And The Governing Factor Of Safety For Overturning And
Sliding - Z Direction
Critical Load Case for Sliding along Z-Direction : 27
Governing Disturbing Force : 218.618 kN
Governing Restoring Force : 330.627 kN
Minimum Sliding Ratio for the Critical Load Case : 1.512
Critical Load Case for Overturning about Z-Direction : 28
Governing Overturning Moment : 939.184 kNm
Governing Resisting Moment : 4299.062 kNm
Minimum Overturning Ratio for the Critical Load Case : 4.577
Shear Calculation
Punching Shear Check
Total Footing Depth, D = 0.50m
Calculated Effective Depth, deff = D - Ccover - 1.0 = 0.42 m
40. 40 | P a g e
For rectangular column, = Bcol / Dcol = 2.14
Effective depth, deff, increased until 0.75*Vc Punching Shear Force
Punching Shear Force, Vu = 702.98 kN, Load Case # 21
From ACI Cl.11.12.2.1, bo for column= 3.90 m
Equation 11-33, Vc1 = 2657.25 kN
Equation 11-34, Vc2 = 4368.42 kN
Equation 11-35, Vc3 = 2748.88 kN
Punching shear strength, Vc = 0.75 * minimum of (Vc1, Vc2, Vc3) = 1992.94 kN
0.75 * Vc > Vu hence, OK
One-Way Shear Check
Along X Direction
From ACI Cl.11.3.1.1, Vc = 3032.06 kN
Distance along Z to design for shear, Dz = 4.90 m
41. 41 | P a g e
Check that 0.75 * Vc > Vux where Vux is the shear force for the critical load cases at a
distance deff from the face of the column caused by bending about the X axis.
From above calculations, 0.75 * Vc = 2274.05 kN
Critical load case for Vux is # 21 320.71 kN
0.75 * Vc > Vux hence, OK
Along Z Direction
From ACI Cl.11.3.1.1, Vc = 3032.06 kN
Distance along X to design for shear, Dx = 3.50 m
Check that 0.75 * Vc > Vuz where Vuz is the shear force for the critical load cases at
a distance deff from the face of the column caused by bending about the Z axis.
From above calculations, 0.75 * Vc = 2274.05 kN
42. 42 | P a g e
Critical load case for Vuz is # 21 291.95 kN
0.75 * Vc > Vuz hence, OK
Design for Flexure about Z axis
Calculate the flexural reinforcement along the X direction of the footing. Find the
area of steel required, A, as per Section 3.8 of Reinforced Concrete Design (5th ed.)
by Salmon and Wang (Ref. 1)
Critical Load Case # 21
The strength values of steel and concrete used in the formulae are in ksi
Factor from ACI Cl.10.2.7.3 for Fc' 4 ksi, 0.85
From ACI Cl. 10.3.2, = 0.02573
From ACI Cl. 10.3.3, = 0.01929
From ACI Cl. 7.12.2, = 0.00180
From Ref. 1, Eq. 3.8.4a, constant m = 19.53
43. 43 | P a g e
Calculate reinforcement ratio for critical load case
Design for flexure about Z axis is
performed at the face of the column at
a distance, Dx =
3.93 m
Ultimate moment, 643.30 kNm
Nominal moment capacity, Mn = 714.78 kNm
Required = 0.00180
Since OK
Area of Steel Required, As = 10.19 in2
Find suitable bar arrangement between minimum and maximum rebar
sizes
Available development length for bars, DL = 3875.00 mm
Try bar size # 8 Area of one bar = 0.08 in2
Number of bars required, Nbar = 131
Because the number of bars is rounded up, make sure new reinforcement
ratio < max
Total reinforcement area, As_total = Nbar * (Area of one bar) = 10.21 in2
deff = D - Ccover - 0.5 * (dia. of one bar) = 0.45 m
Reinforcement ratio, = 0.00172
From ACI Cl.7.6.1, minimum req'd clear
distance between bars, Cd =
max (Diameter of one bar, 1.0, Min.
User Spacing) =
65.32 mm
Check to see if width is sufficient to accomodate bars
44. 44 | P a g e
Design for Flexure about X axis
Calculate the flexural reinforcement along the Z direction of the footing. Find the
area of steel required, A, as per Section 3.8 of Reinforced Concrete Design (5th ed.)
by Salmon and Wang (Ref. 1)
Critical Load Case # 21
The strength values of steel and concrete used in the formulae are in ksi
Factor from ACI Cl.10.2.7.3 for Fc' 4 ksi, 0.85
From ACI Cl. 10.3.2, = 0.02573
From ACI Cl. 10.3.3, = 0.01929
From ACI Cl.7.12.2, = 0.00180
From Ref. 1, Eq. 3.8.4a, constant m = 19.53
Calculate reinforcement ratio for critical load case
Design for flexure about X axis is
performed at the face of the column at
a distance, Dz =
4.47 m
Ultimate moment, 743.82 kNm
45. 45 | P a g e
Nominal moment capacity, Mn = 826.46 kNm
Required = 0.00180
Since OK
Area of Steel Required, As = 10.00 in2
Find suitable bar arrangement between minimum and maximum rebar
sizes
Available development length for bars, DL = 4075.00 mm
Try bar size # 8 Area of one bar = 0.08 in2
Number of bars required, Nbar = 129
Because the number of bars is rounded up, make sure new reinforcement
ratio < max
Total reinforcement area, As_total = Nbar * (Area of one bar) = 10.05 in2
deff = D - Ccover - 0.5 * (dia. of one bar) = 0.42 m
Reinforcement ratio, = 0.00179
From ACI Cl.7.6.1, minimum req'd clear
distance between bars, Cd =
max (Diameter of one bar, 1.0, Min.
User Spacing) =
58.34 mm
Check to see if width is sufficient to accomodate bars
Bending moment for uplift cases will be calculated based solely on selfweight, soil
depth and surcharge loading.
As the footing size has already been determined based on all servicebility load cases,
and design moment calculation is based on selfweight, soil depth and surcharge
only, top reinforcement value for all pure uplift load cases will be the same.
46. 46 | P a g e
Design For Top Reinforcement About Z Axis
Calculate the flexural reinforcement along the X direction of the footing.
Find the area of steel required
The strength values of steel and concrete used in the formulae are in ksi
Factor from ACI Cl.10.2.7.3 for Fc' 4 ksi, 0.85
From ACI Cl. 10.3.2, = 0.02573
From ACI Cl. 10.3.3, = 0.01929
From ACI Cl. 7.12.2, = 0.00180
From Ref. 1, Eq. 3.8.4a, constant m = 19.53
Calculate reinforcement ratio for critical load case
Design for flexure about A axis is
performed at the face of the column at
a distance, Dx =
4.13 m
Ultimate moment, 0.00 kNm
Nominal moment capacity, Mn = 0.00 kNm
Required = 0.00180
Since OK
Area of Steel Required, As = 10.00 in2
Find suitable bar arrangement between minimum and maximum rebar
sizes
47. 47 | P a g e
Design For Top Reinforcement About X Axis
First load case to be in pure uplift # 0
Calculate the flexural reinforcement along the Z direction of the footing.
Find the area of steel required
The strength values of steel and concrete used in the formulae are in ksi
Factor from ACI Cl.10.2.7.3 for Fc' 4 ksi, 0.85
From ACI Cl. 10.3.2, = 0.02573
From ACI Cl. 10.3.3, = 0.01929
From ACI Cl.7.12.2, = 0.00180
From Ref. 1, Eq. 3.8.4a, constant m = 19.53
Calculate reinforcement ratio for critical load case
Design for flexure about A axis is
performed at the face of the column at
a distance, Dx =
3.93 m
Ultimate moment, 0.00 kNm
Nominal moment capacity, Mn = 0.00 kNm
Required = 0.00180
Since OK
Area of Steel Required, As = 10.19 in2
Find suitable bar arrangement between minimum and maximum rebar
sizes
48. 48 | P a g e
Foundation geometry
Isolated Footing 22
49. 49 | P a g e
Input Values
Footing Geomtery
Footing Thickness (Ft) : 500.00 mm
Footing Length - X (Fl) : 1000.00 mm
Footing Width - Z (Fw) : 1000.00 mm
Eccentricity along X (Oxd) : 0.00 mm
Eccentricity along Z (Ozd) : 0.00 mm
Column Dimensions
Column
Shape :
Rectangular
Column
Length - X
(Pl) :
0.35 m
Column
Width - Z
(Pw) :
0.75 m
Pedestal
Include
Pedestal?
No
Pedestal
Shape :
N/A
Pedestal
Height (Ph) :
N/A
Pedestal
Length - X
(Pl) :
N/A
Pedestal
Width - Z
(Pw) :
N/A
Design Parameters
Concrete and Rebar Properties
50. 50 | P a g e
Unit Weight of Concrete : 25.000 kN/m3
Strength of Concrete : 25.000 N/mm2
Yield Strength of Steel : 415.000 N/mm2
Minimum Bar Size : # 6
Maximum Bar Size : # 40
Minimum Bar Spacing : 50.00 mm
Maximum Bar Spacing : 500.00 mm
Pedestal Clear Cover (P, CL) : 50.00 mm
Footing Clear Cover (F, CL) : 50.00 mm
Soil Properties
Soil Type : UnDrained
Unit Weight : 22.00 kN/m3
Soil Bearing Capacity : 200.00 kN/m2
Soil Surcharge : 0.00 kN/m2
Depth of Soil above Footing : 0.00 mm
Undrained Shear Strength : 0.00 N/mm2
Sliding and Overturning
Coefficient of Friction : 0.50
Factor of Safety Against Sliding : 1.50
Factor of Safety Against Overturning : 1.50
------------------------------------------------------
53. 53 | P a g e
Reduction of force due to buoyancy = -0.00 kN
Effect due to adhesion = 0.00 kN
Min. area required from bearing pressure, Amin = P / qmax = 3.203 m2
Area from initial length and width, Ao = Lo * Wo = 1.00 m2
Final Footing Size
Length (L2) = 6.55 m Governing Load Case : # 28
Width (W2) = 6.55 m Governing Load Case : # 28
Depth (D2) = 0.50 m Governing Load Case : # 28
Area (A2) = 42.90 m2
Pressures at Four Corners
Load Case
Pressure at
corner 1
(q1)
(kN/m^2)
Pressure at
corner 2
(q2)
(kN/m^2)
Pressure at
corner 3
(q3)
(kN/m^2)
Pressure at
corner 4
(q4)
(kN/m^2)
Area of footing
in uplift (Au)
(m2
)
18 31.0236 22.9815 23.2604 31.3025 -0.0000
18 31.0236 22.9815 23.2604 31.3025 -0.0000
21 16.8542 16.2908 30.5740 31.1373 -0.0000
18 31.0236 22.9815 23.2604 31.3025 -0.0000
If Au is zero, there is no uplift and no pressure adjustment is necessary. Otherwise,
to account for uplift, areas of negative pressure will be set to zero and the pressure
will be redistributed to remaining corners.
54. 54 | P a g e
Summary of Adjusted Pressures at 4 corners Four Corners
Load Case
Pressure at
corner 1 (q1)
(kN/m^2)
Pressure at
corner 2 (q2)
(kN/m^2)
Pressure at
corner 3 (q3)
(kN/m^2)
Pressure at
corner 4 (q4)
(kN/m^2)
18 31.0236 22.9815 23.2604 31.3025
18 31.0236 22.9815 23.2604 31.3025
21 16.8542 16.2908 30.5740 31.1373
18 31.0236 22.9815 23.2604 31.3025
Adjust footing size if necessary.
Check for stability against overturning and sliding
- Factor of safety against sliding Factor of safety against overturning
Load Case
No.
Along X-
Direction
Along Z-
Direction
About X-
Direction
About Z-
Direction
5 8.591 419.533 724.576 20.290
6 1528.905 1.815 5.687 5158.545
7 1.616 347.159 595.886 6.464
55. 55 | P a g e
8 2152.745 4.964 9.536 7438.992
9 77.684 54.975 284.738 380.895
10 93.442 31772.244 72461.427 452.804
11 63.366 44.843 232.259 310.693
12 42.200 53.078 275.476 205.850
13 49.056 51.572 267.451 239.604
14 13.200 59.652 365.102 34.164
15 67.440 4.344 13.130 333.715
16 4.405 40.046 189.993 17.385
17 71.331 8.253 17.637 347.314
18 7.994 74.956 583.845 20.250
19 45.935 2.083 6.415 227.138
20 1.921 34.085 150.320 7.612
21 52.190 4.901 9.962 252.570
22 49.056 51.572 267.451 239.604
23 49.056 51.572 267.451 239.604
24 49.056 51.572 267.451 239.604
25 49.056 51.572 267.451 239.604
26 7.571 93.618 915.493 18.561
27 78.806 1.739 5.378 396.381
28 1.503 35.450 149.604 5.985
29 87.835 4.355 8.733 422.980
30 83.252 58.916 305.147 408.195
31 83.252 58.916 305.147 408.195
32 83.252 58.916 305.147 408.195
33 83.252 58.916 305.147 408.195
Critical Load Case And The Governing Factor Of Safety For Overturning And
Sliding - X Direction
Critical Load Case for Sliding along X-Direction : 28
Governing Disturbing Force : -180.863 kN
Governing Restoring Force : 271.861 kN
Minimum Sliding Ratio for the Critical Load Case : 1.503
56. 56 | P a g e
Critical Load Case for Overturning about X-Direction : 27
Governing Overturning Moment : 437.833 kNm
Governing Resisting Moment : 2354.800 kNm
Minimum Overturning Ratio for the Critical Load Case : 5.378
Critical Load Case And The Governing Factor Of Safety For Overturning And
Sliding - Z Direction
Critical Load Case for Sliding along Z-Direction : 27
Governing Disturbing Force : 206.778 kN
Governing Restoring Force : 359.518 kN
Minimum Sliding Ratio for the Critical Load Case : 1.739
Critical Load Case for Overturning about Z-Direction : 28
Governing Overturning Moment : 297.537 kNm
Governing Resisting Moment : 1780.656 kNm
Minimum Overturning Ratio for the Critical Load Case : 5.985
57. 57 | P a g e
Shear Calculation
Punching Shear Check
Total Footing Depth, D = 0.50m
Calculated Effective Depth, deff = D - Ccover - 1.0 = 0.42 m
For rectangular column, = Bcol / Dcol = 2.14
Effective depth, deff, increased until 0.75*Vc Punching Shear Force
Punching Shear Force, Vu = 614.87 kN, Load Case # 18
From ACI Cl.11.12.2.1, bo for column= 3.90 m
Equation 11-33, Vc1 = 2657.25 kN
Equation 11-34, Vc2 = 4368.42 kN
Equation 11-35, Vc3 = 2748.88 kN
Punching shear strength, Vc = 0.75 * minimum of (Vc1, Vc2, Vc3) = 1992.94 kN
0.75 * Vc > Vu hence, OK
58. 58 | P a g e
One-Way Shear Check
Along X Direction
From ACI Cl.11.3.1.1, Vc = 2309.30 kN
Distance along Z to design for shear, Dz = 4.07 m
Check that 0.75 * Vc > Vux where Vux is the shear force for the critical load cases at a
distance deff from the face of the column caused by bending about the X axis.
From above calculations, 0.75 * Vc = 1731.98 kN
Critical load case for Vux is # 21 253.86 kN
0.75 * Vc > Vux hence, OK
59. 59 | P a g e
Along Z Direction
From ACI Cl.11.3.1.1, Vc = 2309.30 kN
Distance along X to design for shear, Dx = 2.68 m
Check that 0.75 * Vc > Vuz where Vuz is the shear force for the critical load cases at
a distance deff from the face of the column caused by bending about the Z axis.
From above calculations, 0.75 * Vc = 1731.98 kN
Critical load case for Vuz is # 18 298.27 kN
0.75 * Vc > Vuz hence, OK
60. 60 | P a g e
Design for Flexure about Z axis
Calculate the flexural reinforcement along the X direction of the footing. Find the
area of steel required, A, as per Section 3.8 of Reinforced Concrete Design (5th ed.)
by Salmon and Wang (Ref. 1)
Critical Load Case # 18
The strength values of steel and concrete used in the formulae are in ksi
Factor from ACI Cl.10.2.7.3 for Fc' 4 ksi, 0.85
From ACI Cl. 10.3.2, = 0.02573
From ACI Cl. 10.3.3, = 0.01929
From ACI Cl. 7.12.2, = 0.00180
From Ref. 1, Eq. 3.8.4a, constant m = 19.53
Calculate reinforcement ratio for critical load case
Design for flexure about Z axis is
performed at the face of the column at
a distance, Dx =
3.10 m
Ultimate moment, 547.42 kNm
61. 61 | P a g e
Nominal moment capacity, Mn = 608.24 kNm
Required = 0.00180
Since OK
Area of Steel Required, As = 7.76 in2
Find suitable bar arrangement between minimum and maximum rebar
sizes
Available development length for bars, DL = 3050.00 mm
Try bar size # 8 Area of one bar = 0.08 in2
Number of bars required, Nbar = 100
Because the number of bars is rounded up, make sure new reinforcement
ratio < max
Total reinforcement area, As_total = Nbar * (Area of one bar) = 7.79 in2
deff = D - Ccover - 0.5 * (dia. of one bar) = 0.45 m
Reinforcement ratio, = 0.00172
From ACI Cl.7.6.1, minimum req'd clear
distance between bars, Cd =
max (Diameter of one bar, 1.0, Min.
User Spacing) =
65.07 mm
Check to see if width is sufficient to accomodate bars
62. 62 | P a g e
Design for Flexure about X axis
Calculate the flexural reinforcement along the Z direction of the footing. Find the
area of steel required, A, as per Section 3.8 of Reinforced Concrete Design (5th ed.)
by Salmon and Wang (Ref. 1)
Critical Load Case # 21
The strength values of steel and concrete used in the formulae are in ksi
Factor from ACI Cl.10.2.7.3 for Fc' 4 ksi, 0.85
From ACI Cl. 10.3.2, = 0.02573
From ACI Cl. 10.3.3, = 0.01929
From ACI Cl.7.12.2, = 0.00180
From Ref. 1, Eq. 3.8.4a, constant m = 19.53
Calculate reinforcement ratio for critical load case
Design for flexure about X axis is
performed at the face of the column at
a distance, Dz =
3.65 m
Ultimate moment, 447.60 kNm
63. 63 | P a g e
Nominal moment capacity, Mn = 497.34 kNm
Required = 0.00180
Since OK
Area of Steel Required, As = 7.61 in2
Find suitable bar arrangement between minimum and maximum rebar
sizes
Available development length for bars, DL = 2850.00 mm
Try bar size # 8 Area of one bar = 0.08 in2
Number of bars required, Nbar = 98
Because the number of bars is rounded up, make sure new reinforcement
ratio < max
Total reinforcement area, As_total = Nbar * (Area of one bar) = 7.64 in2
deff = D - Ccover - 0.5 * (dia. of one bar) = 0.42 m
Reinforcement ratio, = 0.00178
From ACI Cl.7.6.1, minimum req'd clear
distance between bars, Cd =
max (Diameter of one bar, 1.0, Min.
User Spacing) =
58.41 mm
Check to see if width is sufficient to accomodate bars
Bending moment for uplift cases will be calculated based solely on selfweight, soil
depth and surcharge loading.
As the footing size has already been determined based on all servicebility load cases,
and design moment calculation is based on selfweight, soil depth and surcharge
only, top reinforcement value for all pure uplift load cases will be the same.
Design For Top Reinforcement About Z Axis
Calculate the flexural reinforcement along the X direction of the footing.
Find the area of steel required
64. 64 | P a g e
The strength values of steel and concrete used in the formulae are in ksi
Factor from ACI Cl.10.2.7.3 for Fc' 4 ksi, 0.85
From ACI Cl. 10.3.2, = 0.02573
From ACI Cl. 10.3.3, = 0.01929
From ACI Cl. 7.12.2, = 0.00180
From Ref. 1, Eq. 3.8.4a, constant m = 19.53
Calculate reinforcement ratio for critical load case
Design for flexure about A axis is
performed at the face of the column at
a distance, Dx =
2.90 m
Ultimate moment, 0.00 kNm
Nominal moment capacity, Mn = 0.00 kNm
Required = 0.00180
Since OK
Area of Steel Required, As = 7.61 in2
Find suitable bar arrangement between minimum and maximum rebar
sizes
65. 65 | P a g e
Design For Top Reinforcement About X Axis
First load case to be in pure uplift # 0
Calculate the flexural reinforcement along the Z direction of the footing.
Find the area of steel required
The strength values of steel and concrete used in the formulae are in ksi
Factor from ACI Cl.10.2.7.3 for Fc' 4 ksi, 0.85
From ACI Cl. 10.3.2, = 0.02573
From ACI Cl. 10.3.3, = 0.01929
From ACI Cl.7.12.2, = 0.00180
From Ref. 1, Eq. 3.8.4a, constant m = 19.53
Calculate reinforcement ratio for critical load case
Design for flexure about A axis is
performed at the face of the column at
a distance, Dx =
3.10 m
Ultimate moment, 0.00 kNm
Nominal moment capacity, Mn = 0.00 kNm
Required = 0.00180
Since OK
Area of Steel Required, As = 7.76 in2
Find suitable bar arrangement between minimum and maximum rebar
sizes
66. 66 | P a g e
Conclusion
I had the opportunity to learn how to use STAAD Pro software to analyze and design
two-way solid slab as well as one-way ribbed slab. Also, a hand calculation check on analysis
of the results of typical structural members gave us knowledge about checking the adequacy
of design to meet the criteria set by codes of practice. Furthermore, i was exposed to STAAD
Pro Foundation Software, which gave us new ideas about designing the foundations of a
building.
Additionally, in CE 315 project i had the chance to design a beam, column and foundation.
67. 67 | P a g e
References
ACI Committee. Building Code Requirements for Structural Concrete (ACI 318-08)
and Commentary. Farmington Hills: American Concrete Institute, 2008.
JAMES, K WIGHT and G MACGREGOR JAMES. REINFORCED CONCRETE
Mechanics and Design. New Jersey: Pearson Education, 2012.