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Design of Isolated RCC Footing
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Isolated Footing Design (IS 456-2000)
Design For Isolated Footing 1
Design For Isolated Footing 2
Design For Isolated Footing 5
Design For Isolated Footing 6
Isolated Footing 1
Input Values
Footing Geomtery
Footing No. Group ID Foundation Geometry
- - Length Width Thickness
1 1 0.900 m 0.900 m 0.305 m
2 2 0.900 m 0.900 m 0.305 m
5 3 0.900 m 0.900 m 0.305 m
6 4 0.900 m 0.900 m 0.305 m
Footing No. Footing Reinforcement Pedestal Reinforcement
- Bottom Reinforcement(Mz) Bottom Reinforcement(M
x) Top Reinforcement(M
z) Top Reinforcement(M
x) Main Steel Trans Steel
1 Ø10 @ 195 mm c/c Ø10 @ 195 mm c/c Ø10 @ 195 mm c/c Ø10 @ 195 mm c/c N/A N/A
2 Ø10 @ 195 mm c/c Ø10 @ 195 mm c/c Ø10 @ 195 mm c/c Ø10 @ 195 mm c/c N/A N/A
5 Ø10 @ 195 mm c/c Ø10 @ 195 mm c/c Ø10 @ 195 mm c/c Ø10 @ 195 mm c/c N/A N/A
6 Ø10 @ 195 mm c/c Ø10 @ 195 mm c/c Ø10 @ 195 mm c/c Ø10 @ 195 mm c/c N/A N/A
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Column Dimensions
Pedestal
Design Parameters
Concrete and Rebar Properties
Soil Properties
Sliding and Overturning
Design Type : Calculate Dimension
Footing Thickness (Ft) : 305.000 mm
Footing Length - X (Fl) : 300.000 mm
Footing Width - Z (Fw) : 300.000 mm
Eccentricity along X (Oxd) : 0.000 mm
Eccentricity along Z (Ozd) : 0.000 mm
Column Shape : Rectangular
Column Length - X (Pl) : 0.230 m
Column Width - Z (Pw) : 0.230 m
Include Pedestal? No
Pedestal Shape : N/A
Pedestal Height (Ph) : N/A
Pedestal Length - X (Pl) : N/A
Pedestal Width - Z (Pw) : N/A
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 : Ø10
Maximum Bar Size : Ø32
Minimum Bar Spacing : 50.000 mm
Maximum Bar Spacing : 500.000 mm
Pedestal Clear Cover (P, CL) : 50.000 mm
Footing Clear Cover (F, CL) : 50.000 mm
Soil Type : Drained
Unit Weight : 22.000 kN/m3
Soil Bearing Capacity : 100.000 kN/m2
Soil Surcharge : 5.000 kN/m2
Depth of Soil above Footing : 700.000 mm
Cohesion : 0.000 kN/m2
Min Percentage of Slab : 0.000
Coefficient of Friction : 0.500
Factor of Safety Against Sliding : 1.500
Factor of Safety Against Overturning : 1.500
------------------------------------------------------
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Load Combination/s- Service Stress Level
Load Combination Number
Load Combination Title
1 DL
2 LL
Load Combination/s- Strength Level
Load Combination
Number Load Combination Title
1 DL
2 LL
Applied Loads - Service Stress Level
LC Axial(kN)
Shear X (kN)
Shear Z (kN)
Moment X (kNm)
Moment Z(kNm)
1 30.861 -1.642 -1.642 -1.628 1.628
2 9.000 0.000 0.000 0.000 -0.000
Applied Loads - Strength Level
LC Axial
(kN)
Shear X
(kN)
Shear Z
(kN)
Moment X
(kNm)
Moment Z
(kNm)
1 30.861 -1.642 -1.642 -1.628 1.628
2 9.000 0.000 0.000 0.000 -0.000
------------------------------------------------------
Design Calculations
Footing Size
Initial Length (Lo) = 0.300 m
Initial Width (Wo) = 0.300 m
Uplift force due to buoyancy = 0.000 kN
Effect due to adhesion = 0.000 kN
Area from initial length and width, Ao = L
o X W
o = 0.090 m2
Min. area required from bearing pressure, Amin
= P / qmax
= 0.323 m2
Note: Amin
is an initial estimation.
P = Critical Factored Axial Load(without self weight/buoyancy/soil). q
max = Respective Factored Bearing Capacity.
Final Footing Size
Length (L2) = 0.900 m Governing Load Case : # 1
Width (W2) = 0.900 m Governing Load Case : # 1
Depth (D2) = 0.305 m Governing Load Case : # 1
Area (A2) = 0.810 m2
------------------------------------------------------
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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.
Pressures at Four Corner
Load Case
Pressure at
corner 1 (q1)
(kN/m2)
Pressure at
corner 2 (q2)
(kN/m2)
Pressure at
corner 3 (q3)
(kN/m2)
Pressure at
corner 4 (q4)
(kN/m2)
Area of
footing in
uplift (Au)
(m2)
1 99.8282 64.7927 29.7571 64.7927 0.000
1 99.8282 64.7927 29.7571 64.7927 0.000
2 37.8038 37.8038 37.8038 37.8038 0.000
1 99.8282 64.7927 29.7571 64.7927 0.000
Summary of adjusted Pressures at Four Corner
Load Case
Pressure at
corner 1 (q1)
(kN/m2)
Pressure at
corner 2 (q2)
(kN/m2)
Pressure at
corner 3 (q3)
(kN/m2)
Pressure at
corner 4 (q4)
(kN/m2)
1 99.8282 64.7927 29.7571 64.7927
1 99.8282 64.7927 29.7571 64.7927
2 37.8038 37.8038 37.8038 37.8038
1 99.8282 64.7927 29.7571 64.7927
Details of Out-of-Contact Area (If Any)
Governing load case = N/A
Plan area of footing = 0.810 sq.m
Area not in contact with soil = 0.000 sq.m
% of total area not in contact = 0.000%
------------------------------------------------------
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
1 15.982 15.982 11.096 11.096
2 1607999732.008 1607999732.008 4744917146.887 4744917146.887
Critical Load Case And The Governing Factor Of Safety For Overturning and Sliding X Direction
Critical Load Case for Sliding along X-Direction : 1
Governing Disturbing Force : -1.642 kN
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Governing Restoring Force : 26.241 kN
Minimum Sliding Ratio for the Critical Load Case : 15.982
Critical Load Case for Overturning about X-Direction : 1
Governing Overturning Moment : -2.128 kNm
Governing Resisting Moment : 23.616 kNm
Minimum Overturning Ratio for the Critical Load Case : 11.096
Critical Load Case And The Governing Factor Of Safety For Overturning and Sliding Z Direction
Critical Load Case for Sliding along Z-Direction : 1
Governing Disturbing Force : -1.642 kN
Governing Restoring Force : 26.241 kN
Minimum Sliding Ratio for the Critical Load Case : 15.982
Critical Load Case for Overturning about Z-Direction : 1
Governing Overturning Moment : 2.128 kNm
Governing Resisting Moment : 23.616 kNm
Minimum Overturning Ratio for the Critical Load Case : 11.096
------------------------------------------------------
Moment Calculation
Check Trial Depth against moment (w.r.t. X Axis)
Critical Load Case = #1
Effective Depth = = 0.250 m
Governing moment (Mu) = 2.589 kNm
As Per IS 456 2000 ANNEX G G-1.1C
Limiting Factor1 (Kumax
) = = 0.479107
Limiting Factor2 (Rumax
) = = 3444.291146 kN/m2
Limit Moment Of Resistance (Mumax
) = = 193.737849 kNm
Mu <= M
umax hence, safe
Check Trial Depth against moment (w.r.t. Z Axis)
Critical Load Case = #1
Effective Depth = = 0.250 m
Governing moment (Mu) = 2.589 kNm
As Per IS 456 2000 ANNEX G G-1.1C
Limiting Factor1 (Kumax
) = = 0.479107
Limiting Factor2 (Rumax
) = = 3444.291146 kN/m2
Limit Moment Of Resistance (Mumax
) = = 193.737849 kNm
Mu <= M
umax hence, safe
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------------------------------------------------------
Shear Calculation
Check Trial Depth for one way shear (Along X Axis)
(Shear Plane Parallel to X Axis)
Critical Load Case = #1
DX = 0.250 m
Shear Force(S) = 4.128 kN
Shear Stress(Tv) = 18.347516 kN/m2
Percentage Of Steel(Pt) = 0.1464
As Per IS 456 2000 Clause 40 Table 19
Shear Strength Of Concrete(Tc) = 287.798 kN/m2
Tv< T
c hence, safe
Check Trial Depth for one way shear (Along Z Axis)
(Shear Plane Parallel to Z Axis)
Critical Load Case = #1
DZ = 0.250 m
Shear Force(S) = 4.128 kN
Shear Stress(Tv) = 18.347519 kN/m2
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Percentage Of Steel(Pt) = 0.1464
As Per IS 456 2000 Clause 40 Table 19
Shear Strength Of Concrete(Tc) = 287.798 kN/m2
Tv< T
c hence, safe
Check Trial Depth for two way shear
Critical Load Case = #1
Shear Force(S) = 22.083 kN
Shear Stress(Tv) = 46.006 kN/m2
As Per IS 456 2000 Clause 31.6.3.1
Ks = = 1.000
Shear Strength(Tc)= = 1250.0000 kN/m2
Ks x T
c = 1250.0000 kN/m2
Tv<= K
s x T
c hence, safe
------------------------------------------------------
Reinforcement Calculation
Calculation of Maximum Bar Size
Along X Axis
Bar diameter corresponding to max bar size (db) = 10 mm
As Per IS 456 2000 Clause 26.2.1
Development Length(ld) = = 0.403 m
Allowable Length(ldb
) = = 0.285 m
ldb
>ld hence, unsafe for
straight bars
Along Z Axis
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Based on spacing reinforcement increment; provided reinforcement is
Bar diameter corresponding to max bar size(db) = 10 mm
As Per IS 456 2000 Clause 26.2.1
Development Length(ld) = = 0.403 m
Allowable Length(ldb
) = = 0.285 m
ldb
>ld hence, unsafe for
straight bars
Bottom Reinforcement Design
Along Z Axis
For moment w.r.t. X Axis (Mx)
As Per IS 456 2000 Clause 26.5.2.1
Critical Load Case = #1
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 28.745 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Ø10 @ 195.000 mm o.c.
Along X Axis
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Based on spacing reinforcement increment; provided reinforcement is
For moment w.r.t. Z Axis (Mz)
As Per IS 456 2000 Clause 26.5.2.1
Critical Load Case = #1
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 28.745 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Ø10 @ 195.000 mm o.c.
Top Reinforcement Design
Along Z Axis
Page 9 of 45Isolated Footing Design
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Based on spacing reinforcement increment; provided reinforcement is
Based on spacing reinforcement increment; provided reinforcement is
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 329.400 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Governing Moment = 1.573 kNm
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Ø10 @ 195 mm o.c.
Along X Axis
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 329.400 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Governing Moment = 1.573 kNm
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
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Ø10 @ 195 mm o.c.
------------------------------------------------------
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Isolated Footing 2
Input Values
Footing Geomtery
Column Dimensions
Pedestal
Design Type : Calculate Dimension
Footing Thickness (Ft) : 305.000 mm
Footing Length - X (Fl) : 300.000 mm
Footing Width - Z (Fw) : 300.000 mm
Eccentricity along X (Oxd) : 0.000 mm
Eccentricity along Z (Ozd) : 0.000 mm
Column Shape : Rectangular
Column Length - X (Pl) : 0.230 m
Column Width - Z (Pw) : 0.230 m
Include Pedestal? No
Pedestal Shape : N/A
Pedestal Height (Ph) : N/A
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Design Parameters
Concrete and Rebar Properties
Soil Properties
Sliding and Overturning
Pedestal Length - X (Pl) : N/A
Pedestal Width - Z (Pw) : N/A
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 : Ø10
Maximum Bar Size : Ø32
Minimum Bar Spacing : 50.000 mm
Maximum Bar Spacing : 500.000 mm
Pedestal Clear Cover (P, CL) : 50.000 mm
Footing Clear Cover (F, CL) : 50.000 mm
Soil Type : Drained
Unit Weight : 22.000 kN/m3
Soil Bearing Capacity : 100.000 kN/m2
Soil Surcharge : 5.000 kN/m2
Depth of Soil above Footing : 700.000 mm
Cohesion : 0.000 kN/m2
Min Percentage of Slab : 0.000
Coefficient of Friction : 0.500
Factor of Safety Against Sliding : 1.500
Factor of Safety Against Overturning : 1.500
------------------------------------------------------
Load Combination/s- Service Stress Level
Load Combination Number
Load Combination Title
1 DL
2 LL
Load Combination/s- Strength Level
Load Combination
Number Load Combination Title
1 DL
2 LL
Applied Loads - Service Stress Level
LC Axial(kN)
Shear X (kN)
Shear Z (kN)
Moment X (kNm)
Moment Z(kNm)
1 30.861 1.642 -1.642 -1.628 -1.628
2 9.000 0.756 0.000 0.000 -0.749
Applied Loads - Strength Level
LC Axial(kN)
Shear X (kN)
Shear Z (kN)
Moment X (kNm)
Moment Z(kNm)
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1 30.861 1.642 -1.642 -1.628 -1.628
2 9.000 0.756 0.000 0.000 -0.749
------------------------------------------------------
Design Calculations
Footing Size
Initial Length (Lo) = 0.300 m
Initial Width (Wo) = 0.300 m
Uplift force due to buoyancy = 0.000 kN
Effect due to adhesion = 0.000 kN
Area from initial length and width, Ao = L
o X W
o = 0.090 m2
Min. area required from bearing pressure, Amin
= P / qmax
= 0.323 m2
Note: Amin
is an initial estimation.
P = Critical Factored Axial Load(without self weight/buoyancy/soil). q
max = Respective Factored Bearing Capacity.
Final Footing Size
Length (L2) = 0.900 m Governing Load Case : # 1
Width (W2) = 0.900 m Governing Load Case : # 1
Depth (D2) = 0.305 m Governing Load Case : # 1
Area (A2) = 0.810 m2
------------------------------------------------------
Pressures at Four Corner
Load Case
Pressure at
corner 1 (q1)
(kN/m2)
Pressure at
corner 2 (q2)
(kN/m2)
Pressure at
corner 3 (q3)
(kN/m2)
Pressure at
corner 4 (q4)
(kN/m2)
Area of
footing in
uplift (Au)
(m2)
1 64.7927 99.8282 64.7927 29.7571 0.000
1 64.7927 99.8282 64.7927 29.7571 0.000
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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.
1 64.7927 99.8282 64.7927 29.7571 0.000
1 64.7927 99.8282 64.7927 29.7571 0.000
Summary of adjusted Pressures at Four Corner
Load Case
Pressure at
corner 1 (q1)
(kN/m2)
Pressure at
corner 2 (q2)
(kN/m2)
Pressure at
corner 3 (q3)
(kN/m2)
Pressure at
corner 4 (q4)
(kN/m2)
1 64.7927 99.8282 64.7927 29.7571
1 64.7927 99.8282 64.7927 29.7571
1 64.7927 99.8282 64.7927 29.7571
1 64.7927 99.8282 64.7927 29.7571
Details of Out-of-Contact Area (If Any)
Governing load case = N/A
Plan area of footing = 0.810 sq.m
Area not in contact with soil = 0.000 sq.m
% of total area not in contact = 0.000%
------------------------------------------------------
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
1 15.982 15.982 11.096 11.096
2 20.256 1607999732.008 4744917146.887 14.063
Critical Load Case And The Governing Factor Of Safety For Overturning and Sliding X Direction
Critical Load Case for Sliding along X-Direction : 1
Governing Disturbing Force : 1.642 kN
Governing Restoring Force : 26.241 kN
Minimum Sliding Ratio for the Critical Load Case : 15.982
Critical Load Case for Overturning about X-Direction : 1
Governing Overturning Moment : -2.128 kNm
Governing Resisting Moment : 23.616 kNm
Minimum Overturning Ratio for the Critical Load Case : 11.096
Critical Load Case And The Governing Factor Of Safety For Overturning and Sliding Z Direction
Critical Load Case for Sliding along Z-Direction : 1
Governing Disturbing Force : -1.642 kN
Governing Restoring Force : 26.241 kN
Minimum Sliding Ratio for the Critical Load Case : 15.982
Critical Load Case for Overturning about Z-Direction : 1
Governing Overturning Moment : -2.128 kNm
Governing Resisting Moment : 23.616 kNm
Minimum Overturning Ratio for the Critical Load Case : 11.096
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------------------------------------------------------
Moment Calculation
Check Trial Depth against moment (w.r.t. X Axis)
Critical Load Case = #1
Effective Depth = = 0.250 m
Governing moment (Mu) = 2.589 kNm
As Per IS 456 2000 ANNEX G G-1.1C
Limiting Factor1 (Kumax
) = = 0.479107
Limiting Factor2 (Rumax
) = = 3444.291146 kN/m2
Limit Moment Of Resistance (Mumax
) = = 193.737849 kNm
Mu <= M
umax hence, safe
Check Trial Depth against moment (w.r.t. Z Axis)
Critical Load Case = #1
Effective Depth = = 0.250 m
Governing moment (Mu) = 2.590 kNm
As Per IS 456 2000 ANNEX G G-1.1C
Limiting Factor1 (Kumax
) = = 0.479107
Limiting Factor2 (Rumax
) = = 3444.291146 kN/m2
Limit Moment Of Resistance (Mumax
) = = 193.737849 kNm
Mu <= M
umax hence, safe
------------------------------------------------------
Shear Calculation
Check Trial Depth for one way shear (Along X Axis)
(Shear Plane Parallel to X Axis)
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Critical Load Case = #1
DX = 0.250 m
Shear Force(S) = 4.128 kN
Shear Stress(Tv) = 18.347516 kN/m2
Percentage Of Steel(Pt) = 0.1464
As Per IS 456 2000 Clause 40 Table 19
Shear Strength Of Concrete(Tc) = 287.798 kN/m2
Tv< T
c hence, safe
Check Trial Depth for one way shear (Along Z Axis)
(Shear Plane Parallel to Z Axis)
Critical Load Case = #1
DZ = 0.250 m
Shear Force(S) = 4.128 kN
Shear Stress(Tv) = 18.347520 kN/m2
Percentage Of Steel(Pt) = 0.1464
As Per IS 456 2000 Clause 40 Table 19
Shear Strength Of Concrete(Tc) = 287.798 kN/m2
Tv< T
c hence, safe
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Check Trial Depth for two way shear
Critical Load Case = #1
Shear Force(S) = 22.083 kN
Shear Stress(Tv) = 46.006 kN/m2
As Per IS 456 2000 Clause 31.6.3.1
Ks = = 1.000
Shear Strength(Tc)= = 1250.0000 kN/m2
Ks x T
c = 1250.0000 kN/m2
Tv<= K
s x T
c hence, safe
------------------------------------------------------
Reinforcement Calculation
Calculation of Maximum Bar Size
Along X Axis
Bar diameter corresponding to max bar size (db) = 10 mm
As Per IS 456 2000 Clause 26.2.1
Development Length(ld) = = 0.403 m
Allowable Length(ldb
) = = 0.285 m
ldb
>ld hence, unsafe for
straight bars
Along Z Axis
Bar diameter corresponding to max bar size(db) = 10 mm
As Per IS 456 2000 Clause 26.2.1
Development Length(ld) = = 0.403 m
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Based on spacing reinforcement increment; provided reinforcement is
Allowable Length(ldb
) = = 0.285 m
ldb
>ld hence, unsafe for
straight bars
Bottom Reinforcement Design
Along Z Axis
For moment w.r.t. X Axis (Mx)
As Per IS 456 2000 Clause 26.5.2.1
Critical Load Case = #1
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 28.745 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Ø10 @ 195.000 mm o.c.
Along X Axis
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Based on spacing reinforcement increment; provided reinforcement is
For moment w.r.t. Z Axis (Mz)
As Per IS 456 2000 Clause 26.5.2.1
Critical Load Case = #1
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 28.756 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Ø10 @ 195.000 mm o.c.
Top Reinforcement Design
Along Z Axis
Page 20 of 45Isolated Footing Design
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Based on spacing reinforcement increment; provided reinforcement is
Based on spacing reinforcement increment; provided reinforcement is
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 329.400 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Governing Moment = 1.573 kNm
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Ø10 @ 195 mm o.c.
Along X Axis
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 329.400 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Governing Moment = 1.573 kNm
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Page 21 of 45Isolated Footing Design
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Ø10 @ 195 mm o.c.
------------------------------------------------------
Page 22 of 45Isolated Footing Design
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Isolated Footing 5
Input Values
Footing Geomtery
Column Dimensions
Pedestal
Design Type : Calculate Dimension
Footing Thickness (Ft) : 305.000 mm
Footing Length - X (Fl) : 300.000 mm
Footing Width - Z (Fw) : 300.000 mm
Eccentricity along X (Oxd) : 0.000 mm
Eccentricity along Z (Ozd) : 0.000 mm
Column Shape : Rectangular
Column Length - X (Pl) : 0.230 m
Column Width - Z (Pw) : 0.230 m
Include Pedestal? No
Pedestal Shape : N/A
Pedestal Height (Ph) : N/A
Page 23 of 45Isolated Footing Design
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Design Parameters
Concrete and Rebar Properties
Soil Properties
Sliding and Overturning
Pedestal Length - X (Pl) : N/A
Pedestal Width - Z (Pw) : N/A
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 : Ø10
Maximum Bar Size : Ø32
Minimum Bar Spacing : 50.000 mm
Maximum Bar Spacing : 500.000 mm
Pedestal Clear Cover (P, CL) : 50.000 mm
Footing Clear Cover (F, CL) : 50.000 mm
Soil Type : Drained
Unit Weight : 22.000 kN/m3
Soil Bearing Capacity : 100.000 kN/m2
Soil Surcharge : 5.000 kN/m2
Depth of Soil above Footing : 700.000 mm
Cohesion : 0.000 kN/m2
Min Percentage of Slab : 0.000
Coefficient of Friction : 0.500
Factor of Safety Against Sliding : 1.500
Factor of Safety Against Overturning : 1.500
------------------------------------------------------
Load Combination/s- Service Stress Level
Load Combination Number
Load Combination Title
1 DL
2 LL
Load Combination/s- Strength Level
Load Combination
Number Load Combination Title
1 DL
2 LL
Applied Loads - Service Stress Level
LC Axial(kN)
Shear X (kN)
Shear Z (kN)
Moment X (kNm)
Moment Z(kNm)
1 30.861 -1.642 1.642 1.628 1.628
2 9.000 0.000 0.756 0.749 -0.000
Applied Loads - Strength Level
LC Axial(kN)
Shear X (kN)
Shear Z (kN)
Moment X (kNm)
Moment Z(kNm)
Page 24 of 45Isolated Footing Design
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1 30.861 -1.642 1.642 1.628 1.628
2 9.000 0.000 0.756 0.749 -0.000
------------------------------------------------------
Design Calculations
Footing Size
Initial Length (Lo) = 0.300 m
Initial Width (Wo) = 0.300 m
Uplift force due to buoyancy = 0.000 kN
Effect due to adhesion = 0.000 kN
Area from initial length and width, Ao = L
o X W
o = 0.090 m2
Min. area required from bearing pressure, Amin
= P / qmax
= 0.323 m2
Note: Amin
is an initial estimation.
P = Critical Factored Axial Load(without self weight/buoyancy/soil). q
max = Respective Factored Bearing Capacity.
Final Footing Size
Length (L2) = 0.900 m Governing Load Case : # 1
Width (W2) = 0.900 m Governing Load Case : # 1
Depth (D2) = 0.305 m Governing Load Case : # 1
Area (A2) = 0.810 m2
------------------------------------------------------
Pressures at Four Corner
Load Case
Pressure at
corner 1 (q1)
(kN/m2)
Pressure at
corner 2 (q2)
(kN/m2)
Pressure at
corner 3 (q3)
(kN/m2)
Pressure at
corner 4 (q4)
(kN/m2)
Area of
footing in
uplift (Au)
(m2)
1 64.7927 29.7571 64.7927 99.8283 0.000
1 64.7927 29.7571 64.7927 99.8283 0.000
Page 25 of 45Isolated Footing Design
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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.
1 64.7927 29.7571 64.7927 99.8283 0.000
1 64.7927 29.7571 64.7927 99.8283 0.000
Summary of adjusted Pressures at Four Corner
Load Case
Pressure at
corner 1 (q1)
(kN/m2)
Pressure at
corner 2 (q2)
(kN/m2)
Pressure at
corner 3 (q3)
(kN/m2)
Pressure at
corner 4 (q4)
(kN/m2)
1 64.7927 29.7571 64.7927 99.8283
1 64.7927 29.7571 64.7927 99.8283
1 64.7927 29.7571 64.7927 99.8283
1 64.7927 29.7571 64.7927 99.8283
Details of Out-of-Contact Area (If Any)
Governing load case = N/A
Plan area of footing = 0.810 sq.m
Area not in contact with soil = 0.000 sq.m
% of total area not in contact = 0.000%
------------------------------------------------------
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
1 15.982 15.982 11.096 11.096
2 1607999732.008 20.256 14.063 4744917146.887
Critical Load Case And The Governing Factor Of Safety For Overturning and Sliding X Direction
Critical Load Case for Sliding along X-Direction : 1
Governing Disturbing Force : -1.642 kN
Governing Restoring Force : 26.241 kN
Minimum Sliding Ratio for the Critical Load Case : 15.982
Critical Load Case for Overturning about X-Direction : 1
Governing Overturning Moment : 2.128 kNm
Governing Resisting Moment : 23.617 kNm
Minimum Overturning Ratio for the Critical Load Case : 11.096
Critical Load Case And The Governing Factor Of Safety For Overturning and Sliding Z Direction
Critical Load Case for Sliding along Z-Direction : 1
Governing Disturbing Force : 1.642 kN
Governing Restoring Force : 26.241 kN
Minimum Sliding Ratio for the Critical Load Case : 15.982
Critical Load Case for Overturning about Z-Direction : 1
Governing Overturning Moment : 2.128 kNm
Governing Resisting Moment : 23.617 kNm
Minimum Overturning Ratio for the Critical Load Case : 11.096
Page 26 of 45Isolated Footing Design
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------------------------------------------------------
Moment Calculation
Check Trial Depth against moment (w.r.t. X Axis)
Critical Load Case = #1
Effective Depth = = 0.250 m
Governing moment (Mu) = 2.590 kNm
As Per IS 456 2000 ANNEX G G-1.1C
Limiting Factor1 (Kumax
) = = 0.479107
Limiting Factor2 (Rumax
) = = 3444.291146 kN/m2
Limit Moment Of Resistance (Mumax
) = = 193.737849 kNm
Mu <= M
umax hence, safe
Check Trial Depth against moment (w.r.t. Z Axis)
Critical Load Case = #1
Effective Depth = = 0.250 m
Governing moment (Mu) = 2.589 kNm
As Per IS 456 2000 ANNEX G G-1.1C
Limiting Factor1 (Kumax
) = = 0.479107
Limiting Factor2 (Rumax
) = = 3444.291146 kN/m2
Limit Moment Of Resistance (Mumax
) = = 193.737849 kNm
Mu <= M
umax hence, safe
------------------------------------------------------
Shear Calculation
Check Trial Depth for one way shear (Along X Axis)
(Shear Plane Parallel to X Axis)
Page 27 of 45Isolated Footing Design
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Critical Load Case = #1
DX = 0.250 m
Shear Force(S) = 4.128 kN
Shear Stress(Tv) = 18.347530 kN/m2
Percentage Of Steel(Pt) = 0.1464
As Per IS 456 2000 Clause 40 Table 19
Shear Strength Of Concrete(Tc) = 287.798 kN/m2
Tv< T
c hence, safe
Check Trial Depth for one way shear (Along Z Axis)
(Shear Plane Parallel to Z Axis)
Critical Load Case = #1
DZ = 0.250 m
Shear Force(S) = 4.128 kN
Shear Stress(Tv) = 18.347537 kN/m2
Percentage Of Steel(Pt) = 0.1464
As Per IS 456 2000 Clause 40 Table 19
Shear Strength Of Concrete(Tc) = 287.798 kN/m2
Tv< T
c hence, safe
Page 28 of 45Isolated Footing Design
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Check Trial Depth for two way shear
Critical Load Case = #1
Shear Force(S) = 22.083 kN
Shear Stress(Tv) = 46.006 kN/m2
As Per IS 456 2000 Clause 31.6.3.1
Ks = = 1.000
Shear Strength(Tc)= = 1250.0000 kN/m2
Ks x T
c = 1250.0000 kN/m2
Tv<= K
s x T
c hence, safe
------------------------------------------------------
Reinforcement Calculation
Calculation of Maximum Bar Size
Along X Axis
Bar diameter corresponding to max bar size (db) = 10 mm
As Per IS 456 2000 Clause 26.2.1
Development Length(ld) = = 0.403 m
Allowable Length(ldb
) = = 0.285 m
ldb
>ld hence, unsafe for
straight bars
Along Z Axis
Bar diameter corresponding to max bar size(db) = 10 mm
As Per IS 456 2000 Clause 26.2.1
Development Length(ld) = = 0.403 m
Page 29 of 45Isolated Footing Design
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Based on spacing reinforcement increment; provided reinforcement is
Allowable Length(ldb
) = = 0.285 m
ldb
>ld hence, unsafe for
straight bars
Bottom Reinforcement Design
Along Z Axis
For moment w.r.t. X Axis (Mx)
As Per IS 456 2000 Clause 26.5.2.1
Critical Load Case = #1
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 28.756 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Ø10 @ 195.000 mm o.c.
Along X Axis
Page 30 of 45Isolated Footing Design
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Based on spacing reinforcement increment; provided reinforcement is
For moment w.r.t. Z Axis (Mz)
As Per IS 456 2000 Clause 26.5.2.1
Critical Load Case = #1
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 28.745 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Ø10 @ 195.000 mm o.c.
Top Reinforcement Design
Along Z Axis
Page 31 of 45Isolated Footing Design
21-03-2015file:///C:/Staad.foundation%205.3/CalcXsl/footing.xml
Based on spacing reinforcement increment; provided reinforcement is
Based on spacing reinforcement increment; provided reinforcement is
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 329.400 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Governing Moment = 1.573 kNm
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Ø10 @ 195 mm o.c.
Along X Axis
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 329.400 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Governing Moment = 1.573 kNm
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Page 32 of 45Isolated Footing Design
21-03-2015file:///C:/Staad.foundation%205.3/CalcXsl/footing.xml
Ø10 @ 195 mm o.c.
------------------------------------------------------
Page 33 of 45Isolated Footing Design
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Isolated Footing 6
Input Values
Footing Geomtery
Column Dimensions
Pedestal
Design Type : Calculate Dimension
Footing Thickness (Ft) : 305.000 mm
Footing Length - X (Fl) : 300.000 mm
Footing Width - Z (Fw) : 300.000 mm
Eccentricity along X (Oxd) : 0.000 mm
Eccentricity along Z (Ozd) : 0.000 mm
Column Shape : Rectangular
Column Length - X (Pl) : 0.230 m
Column Width - Z (Pw) : 0.230 m
Include Pedestal? No
Pedestal Shape : N/A
Pedestal Height (Ph) : N/A
Page 34 of 45Isolated Footing Design
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Design Parameters
Concrete and Rebar Properties
Soil Properties
Sliding and Overturning
Pedestal Length - X (Pl) : N/A
Pedestal Width - Z (Pw) : N/A
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 : Ø10
Maximum Bar Size : Ø32
Minimum Bar Spacing : 50.000 mm
Maximum Bar Spacing : 500.000 mm
Pedestal Clear Cover (P, CL) : 50.000 mm
Footing Clear Cover (F, CL) : 50.000 mm
Soil Type : Drained
Unit Weight : 22.000 kN/m3
Soil Bearing Capacity : 100.000 kN/m2
Soil Surcharge : 5.000 kN/m2
Depth of Soil above Footing : 700.000 mm
Cohesion : 0.000 kN/m2
Min Percentage of Slab : 0.000
Coefficient of Friction : 0.500
Factor of Safety Against Sliding : 1.500
Factor of Safety Against Overturning : 1.500
------------------------------------------------------
Load Combination/s- Service Stress Level
Load Combination Number
Load Combination Title
1 DL
2 LL
Load Combination/s- Strength Level
Load Combination
Number Load Combination Title
1 DL
2 LL
Applied Loads - Service Stress Level
LC Axial(kN)
Shear X (kN)
Shear Z (kN)
Moment X (kNm)
Moment Z(kNm)
1 30.861 1.642 1.642 1.628 -1.628
2 4.500 0.378 0.378 0.375 -0.375
Applied Loads - Strength Level
LC Axial(kN)
Shear X (kN)
Shear Z (kN)
Moment X (kNm)
Moment Z(kNm)
Page 35 of 45Isolated Footing Design
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1 30.861 1.642 1.642 1.628 -1.628
2 4.500 0.378 0.378 0.375 -0.375
------------------------------------------------------
Design Calculations
Footing Size
Initial Length (Lo) = 0.300 m
Initial Width (Wo) = 0.300 m
Uplift force due to buoyancy = 0.000 kN
Effect due to adhesion = 0.000 kN
Area from initial length and width, Ao = L
o X W
o = 0.090 m2
Min. area required from bearing pressure, Amin
= P / qmax
= 0.323 m2
Note: Amin
is an initial estimation.
P = Critical Factored Axial Load(without self weight/buoyancy/soil). q
max = Respective Factored Bearing Capacity.
Final Footing Size
Length (L2) = 0.900 m Governing Load Case : # 1
Width (W2) = 0.900 m Governing Load Case : # 1
Depth (D2) = 0.305 m Governing Load Case : # 1
Area (A2) = 0.810 m2
------------------------------------------------------
Pressures at Four Corner
Load Case
Pressure at
corner 1 (q1)
(kN/m2)
Pressure at
corner 2 (q2)
(kN/m2)
Pressure at
corner 3 (q3)
(kN/m2)
Pressure at
corner 4 (q4)
(kN/m2)
Area of
footing in
uplift (Au)
(m2)
1 29.7571 64.7927 99.8283 64.7927 0.000
1 29.7571 64.7927 99.8283 64.7927 0.000
Page 36 of 45Isolated Footing Design
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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.
1 29.7571 64.7927 99.8283 64.7927 0.000
1 29.7571 64.7927 99.8283 64.7927 0.000
Summary of adjusted Pressures at Four Corner
Load Case
Pressure at
corner 1 (q1)
(kN/m2)
Pressure at
corner 2 (q2)
(kN/m2)
Pressure at
corner 3 (q3)
(kN/m2)
Pressure at
corner 4 (q4)
(kN/m2)
1 29.7571 64.7927 99.8283 64.7927
1 29.7571 64.7927 99.8283 64.7927
1 29.7571 64.7927 99.8283 64.7927
1 29.7571 64.7927 99.8283 64.7927
Details of Out-of-Contact Area (If Any)
Governing load case = N/A
Plan area of footing = 0.810 sq.m
Area not in contact with soil = 0.000 sq.m
% of total area not in contact = 0.000%
------------------------------------------------------
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
1 15.982 15.982 11.096 11.096
2 34.558 34.558 23.993 23.993
Critical Load Case And The Governing Factor Of Safety For Overturning and Sliding X Direction
Critical Load Case for Sliding along X-Direction : 1
Governing Disturbing Force : 1.642 kN
Governing Restoring Force : 26.241 kN
Minimum Sliding Ratio for the Critical Load Case : 15.982
Critical Load Case for Overturning about X-Direction : 1
Governing Overturning Moment : 2.128 kNm
Governing Resisting Moment : 23.617 kNm
Minimum Overturning Ratio for the Critical Load Case : 11.096
Critical Load Case And The Governing Factor Of Safety For Overturning and Sliding Z Direction
Critical Load Case for Sliding along Z-Direction : 1
Governing Disturbing Force : 1.642 kN
Governing Restoring Force : 26.241 kN
Minimum Sliding Ratio for the Critical Load Case : 15.982
Critical Load Case for Overturning about Z-Direction : 1
Governing Overturning Moment : -2.128 kNm
Governing Resisting Moment : 23.617 kNm
Minimum Overturning Ratio for the Critical Load Case : 11.096
Page 37 of 45Isolated Footing Design
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------------------------------------------------------
Moment Calculation
Check Trial Depth against moment (w.r.t. X Axis)
Critical Load Case = #1
Effective Depth = = 0.250 m
Governing moment (Mu) = 2.590 kNm
As Per IS 456 2000 ANNEX G G-1.1C
Limiting Factor1 (Kumax
) = = 0.479107
Limiting Factor2 (Rumax
) = = 3444.291146 kN/m2
Limit Moment Of Resistance (Mumax
) = = 193.737849 kNm
Mu <= M
umax hence, safe
Check Trial Depth against moment (w.r.t. Z Axis)
Critical Load Case = #1
Effective Depth = = 0.250 m
Governing moment (Mu) = 2.590 kNm
As Per IS 456 2000 ANNEX G G-1.1C
Limiting Factor1 (Kumax
) = = 0.479107
Limiting Factor2 (Rumax
) = = 3444.291146 kN/m2
Limit Moment Of Resistance (Mumax
) = = 193.737849 kNm
Mu <= M
umax hence, safe
------------------------------------------------------
Shear Calculation
Check Trial Depth for one way shear (Along X Axis)
(Shear Plane Parallel to X Axis)
Page 38 of 45Isolated Footing Design
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Critical Load Case = #1
DX = 0.250 m
Shear Force(S) = 4.128 kN
Shear Stress(Tv) = 18.347526 kN/m2
Percentage Of Steel(Pt) = 0.1464
As Per IS 456 2000 Clause 40 Table 19
Shear Strength Of Concrete(Tc) = 287.798 kN/m2
Tv< T
c hence, safe
Check Trial Depth for one way shear (Along Z Axis)
(Shear Plane Parallel to Z Axis)
Critical Load Case = #1
DZ = 0.250 m
Shear Force(S) = 4.128 kN
Shear Stress(Tv) = 18.347536 kN/m2
Percentage Of Steel(Pt) = 0.1464
As Per IS 456 2000 Clause 40 Table 19
Shear Strength Of Concrete(Tc) = 287.798 kN/m2
Tv< T
c hence, safe
Page 39 of 45Isolated Footing Design
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Check Trial Depth for two way shear
Critical Load Case = #1
Shear Force(S) = 22.083 kN
Shear Stress(Tv) = 46.006 kN/m2
As Per IS 456 2000 Clause 31.6.3.1
Ks = = 1.000
Shear Strength(Tc)= = 1250.0000 kN/m2
Ks x T
c = 1250.0000 kN/m2
Tv<= K
s x T
c hence, safe
------------------------------------------------------
Reinforcement Calculation
Calculation of Maximum Bar Size
Along X Axis
Bar diameter corresponding to max bar size (db) = 10 mm
As Per IS 456 2000 Clause 26.2.1
Development Length(ld) = = 0.403 m
Allowable Length(ldb
) = = 0.285 m
ldb
>ld hence, unsafe for
straight bars
Along Z Axis
Bar diameter corresponding to max bar size(db) = 10 mm
As Per IS 456 2000 Clause 26.2.1
Development Length(ld) = = 0.403 m
Page 40 of 45Isolated Footing Design
21-03-2015file:///C:/Staad.foundation%205.3/CalcXsl/footing.xml
Based on spacing reinforcement increment; provided reinforcement is
Allowable Length(ldb
) = = 0.285 m
ldb
>ld hence, unsafe for
straight bars
Bottom Reinforcement Design
Along Z Axis
For moment w.r.t. X Axis (Mx)
As Per IS 456 2000 Clause 26.5.2.1
Critical Load Case = #1
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 28.756 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Ø10 @ 195.000 mm o.c.
Along X Axis
Page 41 of 45Isolated Footing Design
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Based on spacing reinforcement increment; provided reinforcement is
For moment w.r.t. Z Axis (Mz)
As Per IS 456 2000 Clause 26.5.2.1
Critical Load Case = #1
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 28.756 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Ø10 @ 195.000 mm o.c.
Top Reinforcement Design
Along Z Axis
Page 42 of 45Isolated Footing Design
21-03-2015file:///C:/Staad.foundation%205.3/CalcXsl/footing.xml
Based on spacing reinforcement increment; provided reinforcement is
Based on spacing reinforcement increment; provided reinforcement is
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 329.400 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Governing Moment = 1.573 kNm
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Ø10 @ 195 mm o.c.
Along X Axis
Minimum Area of Steel (Astmin
) = 329.400 mm2
Calculated Area of Steel (Ast
) = 329.400 mm2
Provided Area of Steel (Ast,Provided
) = 329.400 mm2
Astmin
<= Ast,Provided
Steel area is accepted
Governing Moment = 1.573 kNm
Selected bar Size (db) = Ø10
Minimum spacing allowed (Smin
) = = 50.000 mm
Selected spacing (S) = 197.500 mm
Smin
<= S <= Smax
and selected bar size < selected maximum bar size...
The reinforcement is accepted.
Page 43 of 45Isolated Footing Design
21-03-2015file:///C:/Staad.foundation%205.3/CalcXsl/footing.xml
Ø10 @ 195 mm o.c.
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Page 44 of 45Isolated Footing Design
21-03-2015file:///C:/Staad.foundation%205.3/CalcXsl/footing.xml
Print Calculation Sheet
Page 45 of 45Isolated Footing Design
21-03-2015file:///C:/Staad.foundation%205.3/CalcXsl/footing.xml
![A Study on RC Columns and Slabs and Restoration of RC ... · PDF fileis used for the design of isolated footing [2]. Isolated RC Rectangular footings were provided for all the columns](https://img.pdfslide.us/doc/110x75/5a78c3be7f8b9a83238c18a6/a-study-on-rc-columns-and-slabs-and-restoration-of-rc-used-for-the-design-of.jpg)
