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Chapter # 7 Design of Two way Slab

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Chapter # 7
Design of Two-Way Slab
Reinforced Concrete Slabs
Reinforced Concrete Slabs are large flat plates that are
supported by reinforced concrete beams, walls, or columns,
by masonry walls, by structural steel beams or columns, or
by the ground.
If a slab is supported on two opposite sides only, it is referred
to as a One-Way Slab because the bending is in one
direction only – that is, perpendicular to the supported edges
If a slab is supported by beams on all four edges, it is
referred to as Two-Way Slab because the bending is in
both direction
Dr. Roz-Ud-Din Nassar
CIEN 422
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Reinforced Concrete Slabs
A one-way slab shows a cylindrical failure, while a two-way
slab fails in bowl action.
In a slab, if the ratio of the long side to the short side is 2 or
more than 2, it is referred to as a one-way slab, otherwise it
is a called a two-way slab
A Two-way slab carries the load in the two perpendicular
directions
The main flexural reinforcement is therefore placed in the
two perpendicular directions
Dr. Roz-Ud-Din Nassar
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Reinforced Concrete Slabs
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The Two Way Slabs
๏ฎ
In two way slab, the load is transmitted in two
directions hence the system is called two way slab
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Types of Two-way Slabs
Flat Plate
Flat Slab
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Types of Two-way Slabs
Slab with Beams
Waffle Slab
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Slab Curvatures and Moments
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Statical Equilibrium of Two-Way Slabs
Consider a floor made up of simply supported planks
supported by simply supported beams.
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Statical Equilibrium of Two-Way Slabs
The floor carries a load of w lb/ft2. The moment per foot
of width in the planks at section A-A is :
๐‘ค๐‘™12
๐‘š=
๐‘“๐‘ก − ๐‘˜๐‘–๐‘๐‘ /๐‘“๐‘ก
8
The total moment in the entire width of the floor is:
๐‘€ = ๐‘ค๐‘™2
๐‘ค๐‘™12
๐‘“๐‘ก − ๐‘˜๐‘–๐‘๐‘ 
8
Which is the familiar equation for the maximum moment
in a simply supported floor of width ๐’๐Ÿ and span ๐’๐Ÿ
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CIEN 422
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Statical Equilibrium of Two-Way Slabs
Moments in a Plank-and-Beam Floor
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Statical Equilibrium of Two-Way Slabs
The planks apply following uniform load on each beam:
๐‘ค๐‘™1
/๐‘“๐‘ก
2
The moment at section B-B in one beam is thus:
๐‘€1๐‘
๐‘ค๐‘™1 ๐‘™22
=
๐‘“๐‘ก − ๐‘˜๐‘–๐‘๐‘ 
2 8
The total moment in both beams is:
๐‘€ = ๐‘ค๐‘™1
Dr. Roz-Ud-Din Nassar
๐‘™22
๐‘“๐‘ก − ๐‘˜๐‘–๐‘๐‘ 
8
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Transfer of Moments in Two-Way Slab
It is important to note that full load was transferred East and
West by the planks, causing a moment equivalent to
๐’˜๐’๐Ÿเต—
๐Ÿ–
in
the planks, and then was transferred North and South by
the beams, causing a similar moment in the beams
Same thing happens in the two-way slab. The total moments
required along sections A-A and B-B respectively, are:
๐‘€ = ๐‘ค๐‘™2
Dr. Roz-Ud-Din Nassar
๐‘™12
8
and
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๐‘€ = ๐‘ค๐‘™1
๐‘™22
8
13
Transfer of Moments in Two-Way Slab
Moments in a Two-Way Slab
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Transfer of Moments in Two-Way Slab
In this case again, the full load was transferred East and
West, and then the full load was transferred North and
South, this time by the slab in both cases
Such mechanism should be true regardless of whether the
structure has one-way slabs and beams, two-way slabs or
some other system
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CIEN 422
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Effect of Beam Stiffness on Moments in Slabs
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Design Methods of Two Way Slabs
• Direct Design Method
• Equivalent Frame Method
• Elastic Yield Line Theory
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Two-Way Slab: Direct Design Method
Steps in Slab Design
1) Choose the layout and type of slab to be used. The choice of type
of slab is strongly affected by architectural and construction
calculations
2) Choose the slab thickness. Generally, the slab thickness is chosen
to prevent excessive deflection in service. Equally important is to
satisfy the shear requirements at both exterior and interior columns
3) Choose the method for computing the design moments (direct
design OR equivalent frame)
4) Compute the positive and negative moments in the slab
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Two-Way Slab: Direct Design Method
Steps in Slab Design
5) Calculate the distribution of moments across the width of the slab.
The lateral distribution of moments within a panel depends on the
geometry of the slab and the stiffness of the beams (if any)
6) If there are beam, a portion of the moment must be assigned to the
beams
7) Reinforcement is designed for the moments from steps 5 and 6
8) The shear strengths at the columns are checked
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CIEN 422
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Limitations on the Use of Direct Design Method
The limitations given by ACI Code Section 13.6.1 are as
under:
1) There must be a minimum of three continuous spans in each
direction. Thus a nine-panel structure (3 by 3) is the smallest that
can be considered
2) Rectangular panels must have a long-span / short-span
ratio not greater than 2
3) Successive span lengths in each direction shall not differ by
more than one-third of the longer span
4) Columns may be offset from the basic rectangular grid of the
building by up to 0.1 times the span parallel to the offset
Dr. Roz-Ud-Din Nassar
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Limitations on the Use of Direct Design Method
5) All the loads must be due to gravity only. The direct design method
cannot be used for unbraced laterally loaded frames, foundations mats,
or prestressed slabs
6) The service live load shall not exceed two times the service dead
load
7) For a panel with beams between supports on all sides the relative
stiffness of the beams in the two perpendicular directions given by:
๐›ผ1 ๐‘™22
๐›ผ2 ๐‘™12
(where ๐›ผ is beam-to-slab stiffness ratio)
The above ratio shall not be less than 0.2 or greater than 5
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Beam-to-Slab Stiffness Ratio ๐›ผ
Slabs are frequently built with beams spanning from column to
column around the perimeter of the building.
These beams act to stiffen the edge of the slab and help to reduce
the reduce the deflections of the exterior panels of the slab.
In the ACI code, the effects of beam stiffness on deflections and
the distribution of moments are expressed as a function of ๐›ผ,
defined as the flexural stiffness 4๐ธ๐ผ Τ๐‘™, of the beam divided by the
flexural stiffness of a width of slab bounded laterally by the centerlines of the adjacent panels on each side of the beam:
๐Ÿ’๐‘ฌ๐’„๐’ƒ ๐‘ฐ๐’ƒ
๐’
๐œถ๐’‡ =
๐Ÿ’๐‘ฌ๐’„๐’” ๐‘ฐ๐’”
๐’
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Beam-to-Slab Stiffness Ratio ๐›ผ
Since the lengths "๐’” of the beam and slab are equal, the equation
reduces to:
๐Ÿ’๐‘ฌ๐’„๐’ƒ ๐‘ฐ๐’ƒ
๐œถ๐’‡ =
๐Ÿ’๐‘ฌ๐’„๐’” ๐‘ฐ๐’”
Where ๐ธ๐‘๐‘ ๐‘Ž๐‘›๐‘‘ ๐ธ๐‘๐‘  are the moduli of elasticity of beam concrete
and slab concrete, respectively, and ๐ผ๐‘ ๐‘Ž๐‘›๐‘‘ ๐ผ๐‘  are the moments of
inertia of uncracked beams and slabs.
The sections considered in computing ๐ผ๐‘ ๐‘Ž๐‘›๐‘‘ ๐ผ๐‘  are shown in
figures on next slide.
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Beam-to-Slab Stiffness Ratio ๐›ผ
๏ฎ
Definition of terms
Ecb = Modulus of elasticity of beam concrete
Ecs = Modulus of elasticity of slab concrete
Ib =
Moment of inertia of uncracked beam section
Is =
Moment of inertia of uncracked slab section
Dr. Roz-Ud-Din Nassar
CIEN 422
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Beam-to-Slab
Stiffness Ratio ๐›ผ๐‘“
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Beam-to-Slab Stiffness Ratio ๐›ผ๐‘“
Cross Section of Beams as Defined in ACI Code 13.2.4
Dr. Roz-Ud-Din Nassar
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Problem # 1
An 8-in. thick slab is provided with an edge beam that has a
total depth of 16 in. and a width of 12 in., as shown in figure.
The slab and the beam are cast monolithically and have the
same concrete strength and the same Ec. Compute “๐œถ๐’‡ ” in
this case.
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CIEN 422
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Problem # 1
20 ๐‘–๐‘›.
Find the centroid
of the L-section
8 ๐‘–๐‘›.
8 ๐‘–๐‘›.
12 ๐‘–๐‘›.
Dr. Roz-Ud-Din Nassar
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8 ๐‘–๐‘›.
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Problem # 1 - Solution
Solution
๐Ÿ’๐‘ฌ๐’„๐’ƒ ๐‘ฐ๐’ƒ
๐œถ๐’‡ =
๐Ÿ’๐‘ฌ๐’„๐’” ๐‘ฐ๐’”
Since:
′
๐‘“๐‘๐‘ ′ = ๐‘“๐‘๐‘
and ๐ธ๐‘๐‘ = ๐ธ๐‘๐‘ 
๐‘ฐ๐’ƒ
→ ๐œถ๐’‡ =
๐‘ฐ๐’”
Dr. Roz-Ud-Din Nassar
CIEN 422
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Problem # 1 - Solution
3
163
8
๐ผ๐‘ = 12 ×
+ 12 × 16 × 12 + 8 ×
+ 8 × 8 × 32
12
12
๐ผ๐‘ = 5205 ๐‘–๐‘›.4
83
๐ผ๐‘  = 126 ×
= 5376 ๐‘–๐‘›.4
12
๐ผ๐‘  = 5376 ๐‘–๐‘›.4
Dr. Roz-Ud-Din Nassar
CIEN 422
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Problem # 1 - Solution
๐Ÿ“๐Ÿ๐ŸŽ๐Ÿ“
๐œถ๐’‡ =
= ๐ŸŽ. ๐Ÿ—๐Ÿ”๐Ÿ–
๐Ÿ“๐Ÿ‘๐Ÿ•๐Ÿ”
Alternatively:
๐‘ฌ๐’„๐’ƒ ๐’ƒ ๐’‚
๐œถ๐’‡ =
๐‘ฌ๐’„๐’” ๐’ ๐’‰
๐Ÿ‘
๐’‡
From graphs:
๐‘Ž
โ„Ž
Dr. Roz-Ud-Din Nassar
= 2 ๐‘Ž๐‘›๐‘‘
๐‘
โ„Ž
=
12
8
= 1.5, we get ๐‘“ = 1.27
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Problem # 1 - Solution
๐‘ฌ๐’„๐’ƒ ๐’ƒ ๐’‚
๐œถ๐’‡ =
๐‘ฌ๐’„๐’” ๐’ ๐’‰
12 16
๐œถ๐’‡ =
126 8
Dr. Roz-Ud-Din Nassar
๐Ÿ‘
๐’‡
3
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× 1.27 = 0.968
32
Division of Slab into Frames for Design
For design, the slab is considered to be series of frames in the
two directions
These frames extend to the middle of the panels on each side
of the column lines
In each span of each of the frames, it is necessary to
compute the total statical moment, Mo
๐‘ค๐‘ข ๐‘™2 ๐‘™๐‘›2
๐‘€๐‘œ =
8
Dr. Roz-Ud-Din Nassar
CIEN 422
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Division of Slab into Frames for Design
๐‘ค๐‘ข ๐‘™2 ๐‘™๐‘›2
๐‘€๐‘œ =
8
๐‘ค๐‘ข = factored load per unit area
๐‘™2 = transverse width of the strip
๐‘™๐‘› = clear span between the columns
In computing ln, circular columns or column capitals of diameter
dc are replaced by equivalent square columns with side lengths
0.886dc.
Dr. Roz-Ud-Din Nassar
CIEN 422
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Division of Slab into Frames for Design
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CIEN 422
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Division of Slab into Frames for Design
Dr. Roz-Ud-Din Nassar
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Problem # 2
Compute the statical
moment in the slab
panels shown in figure
below. Slab has a
thickness of 8 in. and
supports a live load of
100 psf.
Dr. Roz-Ud-Din Nassar
CIEN 422
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Problem # 2 - Solution
Solution:
1. Compute the factored uniform loads
8
๐‘ค๐‘ข = 1.2
× 0.150 ๐‘˜๐‘ ๐‘“ + 1.6 0.100 ๐‘˜๐‘ ๐‘“
12
๐‘ค๐‘ข = 0.280 ๐‘˜๐‘ ๐‘“
Note: Live load reduction must be carried out if allowed by the code
Dr. Roz-Ud-Din Nassar
CIEN 422
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Problem # 2 - Solution
2. Consider panel A
spanning from column
1 to column 2
๐‘ค๐‘ข ๐‘™2 ๐‘™๐‘›2
๐‘€๐‘œ =
8
๐‘™๐‘› = ๐‘๐‘™๐‘’๐‘Ž๐‘Ÿ ๐‘ ๐‘๐‘Ž๐‘› ๐‘œ๐‘“ ๐‘ ๐‘™๐‘Ž๐‘ ๐‘๐‘Ž๐‘›๐‘’๐‘™
1 20
1 24
๐‘™๐‘› = 22 ๐‘“๐‘ก −
๐‘“๐‘ก −
๐‘“๐‘ก
2 12
2 12
๐‘™๐‘› = 20.17 ๐‘“๐‘ก
Dr. Roz-Ud-Din Nassar
CIEN 422
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Problem # 2 - Solution
๐‘™2 = ๐‘ค๐‘–๐‘‘๐‘กโ„Ž ๐‘œ๐‘“ ๐‘ ๐‘™๐‘Ž๐‘ ๐‘๐‘Ž๐‘›๐‘’๐‘™
21
20
๐‘™2 =
๐‘“๐‘ก +
๐‘“๐‘ก
2
2
Hence:
→ ๐‘™2 = 20.50 ๐‘“๐‘ก
๐‘ค๐‘ข ๐‘™2 ๐‘™๐‘›2
๐‘€๐‘œ =
8
0.280 ๐‘˜๐‘ ๐‘“ × 20.5 ๐‘“๐‘ก 20.17 ๐‘“๐‘ก
→ ๐‘€๐‘œ =
8
2
= 292 ๐‘“๐‘ก − ๐‘˜๐‘–๐‘๐‘ 
This moment will be used to design the reinforcement running
parallel to line 1-2 in this panel
Dr. Roz-Ud-Din Nassar
CIEN 422
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Problem # 2 - Solution
3. Consider panel B
spanning from
column 1 to column 4
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Problem # 2 - Solution
Section through slab panel B
For calculation of ๐‘™๐‘› the circular supports are replaced by equivalent square
columns having side length ๐‘1
Dr. Roz-Ud-Din Nassar
= ๐‘‘๐‘
CIEN 422
๐œ‹
2
๐‘œ๐‘Ÿ 0.886๐‘‘๐‘
42
Problem # 2 - Solution
3. Consider panel B spanning
from column 1 to column 4
๐‘™๐‘› = ๐‘๐‘™๐‘’๐‘Ž๐‘Ÿ ๐‘ ๐‘๐‘Ž๐‘› ๐‘œ๐‘“ ๐‘ ๐‘™๐‘Ž๐‘ ๐‘๐‘Ž๐‘›๐‘’๐‘™
1 12
1
24
๐‘™๐‘› = 20๐‘“๐‘ก −
๐‘“๐‘ก −
0.886 ×
๐‘“๐‘ก
2 12
2
12
๐‘™๐‘› = 18.61 ๐‘“๐‘ก
๐‘™2 =
19
22
๐‘“๐‘ก +
๐‘“๐‘ก
2
2
→ ๐‘™2 = 20.50 ๐‘“๐‘ก
Dr. Roz-Ud-Din Nassar
CIEN 422
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Problem # 2 - Solution
๐‘ค๐‘ข ๐‘™2 ๐‘™๐‘›2
๐‘€๐‘œ =
8
0.280 ๐‘˜๐‘ ๐‘“ × 20.5 ๐‘“๐‘ก × 18.16 ๐‘“๐‘ก
→ ๐‘€๐‘œ =
8
2
= 248 ๐‘“๐‘ก − ๐‘˜๐‘–๐‘๐‘ 
This moment will be used to design the reinforcement running
parallel to line 1-4 in this panel
Dr. Roz-Ud-Din Nassar
CIEN 422
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Definition of Column Strip and Middle Strip
The moments vary continuously across the width of
the slab panel
To add in steel placement, the design moments are
averaged over the width of column strips over the
columns and middle strips between the column strips
as shown in figures on next slide
The width of these strips are defined in ACI Section
13.2.1 and 13.2.2 and are illustrated in figures on slides
46 & 47
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Definition of Column Strip and Middle Strip
Middle strips
Column strips
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46
Definition of Column Strip and Middle Strip
Column
strips
Middle
strips
Column
strips
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47
Column Strip and Middle Strip
Four edges fixed and non-supported
on non-deflecting beams
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Four edges fixed on flexible beams
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Positive and Negative Moments in Interior Span
In the direct design method, the total factored moment Mo is
divided into positive and negative factored moments according
to rules given in ACI Section 13.6.3
In interior spans, 65 percent of Mo is assigned to the negativemoment region and 35 percent to the positive-moment regions
The exterior end of an exterior span has considerable less
fixity than the end at the interior support. The division of Mo in
an end span into positive and negative-moment regions is
given in Table on slide 51
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Positive and Negative Moments in Interior Span
Exterior Span
Interior Span
Assignment of positive and negative moment regions
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50
Distribution of Mo in an Exterior Span
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51
Distribution of Moments between Column
Strips and Middle Strips
ACI code 13.6.4 defines the fraction of negative and
positive moments assigned to column strips
The remaining amount of negative and positive moments
is assigned to adjacent half-middle strips
The division is a function of ๐›ผ๐‘“1 × ๐‘™2 Τ๐‘™1 which depend
upon the aspect ratio of the panel ๐‘™2 Τ๐‘™1 and the relative
stiffness ๐›ผ๐‘“1 of the beams (if any) spanning parallel to and
within the column strip
Dr. Roz-Ud-Din Nassar
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52
Percentage Distribution of Interior Negative
Factored Moment to Column Strip
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53
Percentage Distribution of Midspan Positive
Factored Moment to Column Strip
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54
Percentage Distribution of Exterior Negative
Factored Moment to Column Strip
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55
Torsional Stiffness Ratio ๐›ฝ๐‘ก
๐ธ๐‘๐‘ ๐ถ
๐›ฝ๐‘ก =
๐ธ๐‘๐‘  ๐ผ๐‘ 
๐ถ=เท
๐‘ฅ ๐‘ฅ 3๐‘ฆ
1 − 0.63
๐‘ฆ 3
Where:
๐ธ๐‘๐‘ = Modulus of Elasticity of beam concrete
๐ธ๐‘๐‘  = Modulus of Elasticity of slab concrete
๐ผ๐‘  = Moment of inertia of uncracked slab
Dr. Roz-Ud-Din Nassar
CIEN 422
56
Percentage Distribution of Exterior Negative
Factored Moment to Column Strip
Division of edge members for calculation of torsion constant “C”
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57
Minimum Thickness of Two-way Slab
ACI Section 9.5.3 defines minimum thicknesses that
generally are sufficient to limit slab deflections to
acceptable values
Thinner slabs can be used if it can be shown that the
computed slab deflections will not be excessive
For computation of thickness, slabs have been divided
into two categories:
• Slabs without Beams between Interior Columns
• Slabs with Beams between Interior Supports
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58
Thickness of Slabs Without Beams Between Interior
Columns
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Thickness of Slabs With Beams Between Interior Supports
For slabs with beams between interior supports, ACI Code
Section 9.5.3.3 gives the following minimum thicknesses:
A) For ๐›ผ๐‘“๐‘š ≤ 0.2 , the minimum thickness in Table 13-1 shall apply
B) For 0.2 < ๐›ผ๐‘“๐‘š < 2.0 the thickness shall not be less than:
โ„Ž=
๐‘™๐‘› 0.8 + ๐‘“๐‘ฆ Τ20,000
36 + 5๐›ฝ ๐›ผ๐‘“๐‘š − 0.2
but not less than 5 in.
C) For ๐›ผ๐‘“๐‘š > 2.0 the thickness shall not be less than:
๐‘™๐‘› 0.8 + ๐‘“๐‘ฆ Τ20,000
โ„Ž=
36 + 9๐›ฝ
Dr. Roz-Ud-Din Nassar
CIEN 422
but not less than 3.5 in.
60
Thickness of Slabs With Beams Between Interior Supports
D) At discontinuous edges, either an edge beam with a
stiffness ratio ๐›ผ๐‘“ not less than 0.8 shall be provided or slab
thickness shall be increased by at least 10 percent in the
edge panel
In A, B, C, and D above:
โ„Ž = overall thickness
๐‘™๐‘› = clear span of the slab panel under consideration, measured in the
longer direction
๐›ผ๐‘“๐‘š = the average of the values of ๐›ผ๐‘“ for the four sides of the panel
๐›ฝ = longer clear span/shorter clear span of the panel
Dr. Roz-Ud-Din Nassar
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Problem # 3
Figure on slide # 63 shows an interior panel of the flatplate floor in an apartment building. The slab thickness is
5.5 in. The slab supports a design live load of 50 psf and
superimposed dead load of 25 psf for partitions. The
columns and slab have the same strength of concrete.
The story height is 9 ft. Compute the column-strip and
middle-strip moments in the shown direction of the panel.
Dr. Roz-Ud-Din Nassar
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Problem # 3
Dr. Roz-Ud-Din Nassar
CIEN 422
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Problem # 3 - Solution
Solution:
1) Compute the factored loads
5.5
๐‘ž๐‘ข = 1.2
× 150 + 25 + 1.6 50 = 193 ๐‘๐‘ ๐‘“
12
Note: Live load reduction must be carried out if local building code
allows it (Use KLL = 1.0 for two-way slab panels)
2) Compute moments in the shorter span of the slab
a) Compute ๐‘™๐‘› and ๐‘™๐‘› and divide the slab into column and middle strips
Dr. Roz-Ud-Din Nassar
CIEN 422
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Problem # 3 - Solution
10
๐‘™๐‘› = 13.17 ๐‘“๐‘ก −
= 12.33 ๐‘“๐‘ก
12
๐‘™2 = 14.15 ๐‘“๐‘ก
The column strip extends the
smaller of ๐‘™2 Τ4 or ๐‘™1 Τ4 on each
side of the column centerline, as
shown in figure.
Thus column strip extends
13.17Τ4 ๐‘“๐‘ก = 3.29 ๐‘“๐‘ก on each
side of the column centerline.
Dr. Roz-Ud-Din Nassar
CIEN 422
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Problem # 3 - Solution
The total width of the column
strip is 6.58 ft
Each half middle strip extends
from the edge of the column strip
to the centerline of the panel
The total width of the two halfmiddle strips is 14.5 – 6.58 =
7.92 ft
Dr. Roz-Ud-Din Nassar
CIEN 422
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Problem # 3 - Solution
b) Compute ๐‘€๐‘‚
๐‘ž๐‘ข ๐‘™2 ๐‘™๐‘›2
๐‘€๐‘‚ =
8
0.193 × 14.5 × 12.332
→ ๐‘€๐‘‚ =
= 53.2 ๐‘˜๐‘–๐‘ − ๐‘“๐‘ก
8
c) Divide MO into negative and positive moments
From ACI code Section 8.10.4.1
๐‘๐‘’๐‘”๐‘Ž๐‘ก๐‘–๐‘ฃ๐‘’ ๐‘š๐‘œ๐‘š๐‘’๐‘›๐‘ก = −0.65๐‘€๐‘‚ = −0.65 × 53.2 = −34.6 ๐‘˜๐‘–๐‘ − ๐‘“๐‘ก
๐‘ƒ๐‘œ๐‘ ๐‘–๐‘ก๐‘–๐‘ฃ๐‘’ ๐‘š๐‘œ๐‘š๐‘’๐‘›๐‘ก = 0.35๐‘€๐‘‚ = 0.35 × 53.2 = 18.6 ๐‘˜๐‘–๐‘ − ๐‘“๐‘ก
Dr. Roz-Ud-Din Nassar
CIEN 422
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Problem # 3 - Solution
d) Divide the moments between the column and middle strips
From Table 13-3 (slide # 53) for ๐›ผ๐‘“1 ๐‘™2 Τ๐‘™1 = 0 (๐›ผ๐‘“1 = 0 because
there are no beams between columns A and B in this panel)
Column − strip negative moment = 0.75 × −34.6 = −26.0 ๐‘˜๐‘–๐‘ − ๐‘“๐‘ก
Middle − strip negative moment = 0.25 × −34.6 = −8.66 ๐‘˜๐‘–๐‘ − ๐‘“๐‘ก
Dr. Roz-Ud-Din Nassar
CIEN 422
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Problem # 3 - Solution
Process of calculating slab moments
Dr. Roz-Ud-Din Nassar
CIEN 422
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Problem # 3 - Solution
Division of MO into positive and negative moments
Total moments in column and middle strips
Dr. Roz-Ud-Din Nassar
CIEN 422
70
Problem # 3 - Solution
Division of MO into positive and negative moments
Total moments in column and middle strips
Dr. Roz-Ud-Din Nassar
Mapping
of moments with strips
CIEN 422
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Problem # 3 - Solution
Calculation of moments
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