DESIGN OF FOUNDATION FOR SIGNBOARDS Pylon 01 & 02
Document Name 1.00
Dated 15/11/12
General Data
Unit weight of Concrete Unit weight of Reinforcement Bearing Capacity of Soil @ 1m below ground
= = =
3 25 kN/m 3 78.5 kN/m 2 150 kN/m
Vb (Basic wind speed)
=
45 m/s
Vs (site wind speed)
=
Vb x Sa x Sd x Ss x Sp
(Equation 8, BS 6399-2:1997)
Sa (Altitude factor)
=
1
(Cl 2.2.2.2, BS 6399-2:1997)
Sd (Direction Factor)
=
1
(Cl 2.2.2.3, BS 6399-2:1997)
Ss (Seasonal Factor)
=
1
(Cl 2.2.2.4, BS 6399-2:1997)
Sp (Probability Factor)
=
1
(Cl 2.2.2.5, BS 6399-2:1997)
1.1
For Pylon - 1
1.1.1
Calculation of Loads
Vs
=
Ve
=
Sb
=
Ve
=
qe
=
45 m/s Vs x Sb 1.58
(Table 4, BS 6399-2:1997)
71.1 m/s 0.613 x Ve2
qe
=
Height of Signboard, H Width of Signboard, W
= =
10 m 3.2 m
Effective area against wind Wind load on the frame
= =
32 m2 99.16 kN
3.10 kN/m
(Equation 1, BS 6399-2:1997) 2
5.50 m
0.30 m 1.50 m
SIGNBOARD
3.50 m
SIGNBOARD
1 of 6
DESIGN OF FOUNDATION FOR SIGNBOARDS Pylon 01 & 02 = 3.5 m = 5.5 m = 1.5 m
Document Name Length of Foundation, L Width of Foundation, B Depth of Foundation, D
Area of Foundation, Af Volume of Concrete in Foundation
= =
19.25 m2 28.875 m3
Sectional Modulus of Foundation, Zf
=
17.65 m3
Weight of Foundation block, W f
=
721.875 kN
Weight of Structure, W s
=
20 kN
Total Downward load, P
=
741.875 kN
Moment at the base of Foundation, Mf
=
1.1.2 Check for Bearing Pressure Max. Pressure at bottom of Foundation Min. Pressure at bottom of Foundation
= =
1.2 1.2.1
Dated 15/11/12
644.56 kN-m
75.07 kN/m2 2.01 kN/m2
Pressure less than 150kN/m2 Hence Safe
For Pylon - 2 Calculation of Loads
Vs
=
45 m/s
Ve
Vs x Sb
=
Sb
=
Ve
=
qe
=
qe
=
Height of Signboard, H Width of Signboard, W
= =
4m 4.6 m
Effective area against wind Wind load on the frame
= =
18.4 m2 68.36 kN
1.73 77.85 m/s 0.613 x Ve2
(Table 4, BS 6399-2:1997) (Equation 1, BS 6399-2:1997)
3.72 kN/m2
3.50 m
FGL
0.30 m 1.00 m
SIGNBOARD
3.90 m
SIGNBOARD
2 of 6
DESIGN OF FOUNDATION FOR SIGNBOARDS Pylon 01 & 02
Document Name Length of Foundation, L Width of Foundation, B Depth of Foundation, D
= = =
3.9 m 3.5 m 1m
Area of Foundation, Af Volume of Concrete in Foundation
= =
13.65 m2 13.65 m3
Sectional Modulus of Foundation, Zf
=
7.96 m3
Weight of Foundation block, W f
=
341.25 kN
Weight of Structure, W s
=
20 kN
Total Downward load, P
=
361.25 kN
Moment at the base of Foundation, Mf
=
205.08 kN-m
1.2.2 Check for Bearing Pressure Max. Pressure at bottom of Foundation Min. Pressure at bottom of Foundation
= =
1.3
52.22 kN/m2 0.71 kN/m2
Dated 15/11/12
Pressure less than 150kN/m2 Hence Safe
Reinforcement Calculation As the foundations provided are of block type, hence structural calculation is not required & reinforcement is provided as per engineering judgement Reinforcement Provided is
16 dia
@
200 c/c
3 of 6
1.00
General Data
Unit weight of Concrete Unit weight of Reinforcement Bearing Capacity of Soil @ 1m below ground
= = =
3 25 kN/m 3 78.5 kN/m 2 150 kN/m
Vb (Basic wind speed)
=
45 m/s
Vs (site wind speed)
=
Vb x Sa x Sd x Ss x Sp
(Equation 8, BS 6399-2:1997)
Sa (Altitude factor)
=
1
(Cl 2.2.2.2, BS 6399-2:1997)
Sd (Direction Factor)
=
1
(Cl 2.2.2.3, BS 6399-2:1997)
Ss (Seasonal Factor)
=
1
(Cl 2.2.2.4, BS 6399-2:1997)
Sp (Probability Factor)
=
1
(Cl 2.2.2.5, BS 6399-2:1997)
1.1
For Pylon - 1
1.1.1
Calculation of Loads
Vs
=
Ve
=
Sb
=
Ve
=
qe
=
qe
=
Height of Signboard, H Width of Signboard, W
= =
Effective area against wind Wind load on the frame
= =
Vs x Sb 1.73 77.85 m/s 0.613 x Ve2
(Equation 1, BS 6399-2:1997)
10 m 3.2 m 32 m2 118.89 kN
5.00 m Case (I) Wind
1.50 m
SIGNBOARD
Case (II) Wind
3.50 m
(Table 4, BS 6399-2:1997)
3.72 kN/m2
SIGNBOARD
0.50 m
45 m/s
A
B
Length of Foundation, L Width of Foundation, B Depth of Foundation, D
= = =
5.5 m 3.5 m 1.5 m
Area of Foundation, Af Volume of Concrete in Foundation
= =
19.25 m2 28.875 m3
Sectional Modulus of Foundation, Zf
=
11.23 m3
Weight of Foundation block, W f
=
721.875 kN
Weight of Structure, W s
=
20 kN
Total Downward load, P
=
741.875 kN
Moment at the base of Fdn due to wind, Mw
=
772.75 kN-m
= =
1222.403 kN-m -2857.91 kN-m
= =
2767.910 kN-m -1312.40 kN-m
Case (I) Moment about A Moment about B Case (II) Moment about A Moment about B 1.1.2
Check for Bearing Pressure
Max. Pressure at bottom of Foundation Min. Pressure at bottom of Foundation
= =
285.03 kN/m2 -215.97 kN/m2
