This document discusses how to calculate structural loads on buildings from dead loads, live loads, and wind loads. It provides the following steps: 1. Calculate the dead load from the self-weight of structural elements like the roof, trusses, columns, and foundations. 2. Calculate the live load on the trusses and columns from occupancy. 3. Determine the design wind speed for the location based on weather zone and terrain. Then calculate the wind pressure and wind force on walls and roofs using the wind pressure equation and applying a safety factor. The goal is to understand how to properly design structures to support expected loads by analyzing load paths and calculating loads at each level from the top

1. Vigyan Ashram, Pabal

2. Why should you know how to design a
structure?

3. Step 1 – What is the load on the
structure?
1) Dead Load
 Self weight
 Static loads
2) Dynamic Load
 Wind
 Rain
 People
 Loading/Unloading

4. Tractor Shed
10m
4m
9m
5m
Truss
Column
Foundations

5. Dead Load
Self weight
Golden Rule:
Work top to bottom
1. Truss
2. Column
3. Foundations

6. 1. Load on Truss
10m
4m
Steel Sheet – 10kg/m2
Mass 1 Truss – 100kg
Area of roof (m2) = x x
10 m 4 m 2 = 80 m2
Mass of roof (kg) = x
Weight of roof (N) = x
=
=
80 m2 10 kg/m2 800 kg
800 kg 10 8000 N

7. Weight of 1 truss (N) = x
1. Load on Truss
10m
4m
Steel Sheet –
1kg/m2
Mass 1 Truss –
100kg
100 kg 10
8000N
= 1000 N

8. Total weight on trusses (N) = +
1. Load on Truss
10m
4m
Steel Sheet –
1kg/m2
Mass 1 Truss –
100kg
3000 N
8000N
= 11,000 N
1000 N 1000 N 1000 N
8000 N

9. Activity
 How much roof
weight must your
structure support?
Plastic Sheet – 4.5 kg/m2
Mass 2’ PVC Pipe – 0.75 kg/m
Mass bamboo 1’ – 0.2 kg/m
Mass steel pipe 0.5’ – 0.36 kg/m
Mass steel pipe 0.75’ – 0.5 kg/m
Mass steel pipe 1’ – 0.75 kg/m
Area of roof (m2) = x x
Mass of roof (kg) = x
Weight of roof (N) = x
10 m 4 m 2
=
=
=
80 m2
80 m2
10 kg/m2
800 kg
800 kg 10
8000 N
Weight of 1 truss (N) = x
100 kg 10
= 1000 N
Total weight on trusses (N) = + 3000 N
= 11,000 N
8000 N

10. 2. Load on Column
5m
Mass 1 Column – 10 kg/m
8000N
1000 N 1000 N 1000 N
Mass 1 pole = x
Weight 1 pole = x
=
=
50 kg
5m 10kg/m
50kg
500 N
10

11. 2. Load on Column
5m
Mass 1 Column – 10 kg/m
11,000N
500 N
500 N
500 N
500 N
500 N
500 N
Force on each column = +
11,000 N 3000 N
= 14,000 N

12. Try it youself!
 How much weight
does each lower
support hold?
Mass 1 pole = x
Weight 1 pole = x
=
=
50 kg
5m 10kg/m
50kg
500 N
10
Force on columns = +
11,000 N 3000 N
= 14,000 N
Mass 2’ PVC Pipe – 0.75 kg/m
Mass bamboo 1’ – 0.2 kg/m
Mass steel pipe 0.5’ – 0.36 kg/m
Mass steel pipe 0.75’ – 0.5 kg/m
Mass steel pipe 1’ – 0.75 kg/m

13. Weight of Foundations = x
3. Load on Foundations
14,000N
Force on Foundations = +
2000kg 10 =
34,000N
Mass Foundations – 2000kg
20,000N
14,000N 20,000N
=

14. Try it yourself:
 How much weight do
the bottom supports
hold?
Mass 2’ PVC Pipe – 0.75 kg/m
Mass bamboo 1’ – 0.2 kg/m
Mass steel pipe 0.5’ – 0.36 kg/m
Mass steel pipe 0.75’ – 0.5 kg/m
Mass steel pipe 1’ – 0.75 kg/m
Force on Foundations = +
11,000 N 20,000 N
= 34,000N

15. Extreme Wind
normal air
pressure
low air pressure
Tornado

16. Windflow over buildings
high
pressure
low
pressure
low
pressure

18. So how do I calculate wind load?
What things do you think affect wind load?

19. Zone Windspeed
(m/s)
55
50
47
44
39
33
Step 1 – Highest Windspeed
Pabal – 39 m/s

20. Wind speed is affected by local terrain
If you are on a hill, increase the wind speed
by multiplying by 1.1
Safety Factor
Design wind speed = 1.1 x 39 m/s
= 43 m/s

21. Pressure is the force per square metre on the
building
Wind Pressure
Pressure (N/m2) = 0.6 x windspeed2
= x x
43
0.6
1109 N/m2
=
43
1m
1m

22. Wind force is the specific force on a particular part
of the building
Safety Factor: account for internal pressure
changes with a safety factor of 2
Wind Force
Force (N) = Pressure (N/m2) x Area (m2) x Safety Factor

23. Wind Force
Force (N) = Pressure (N/m2) x Area (m2) x Safety Factor
Force On Wall (N) = x x
Area Of Wall (m2) = x
=
=
9m 5m
45 m2
2
1109 N/m2
9,9810 N
9m
5m
Wind Pressure =
1325 N/m2
Safety Factor = 2
45 m2
Wind Force (N)

24. Wind Force
Force (N) = Pressure (N/m2) x Area (m2) x Safety Factor
Force On Roof (N) = x x
Area Of Roof (m2) = x
=
=
10m 4m
40 m2
2
1109 N/m2
8,8720 N
10m
4m
Wind Pressure =
1325 N/m2
Safety Factor = 2
Wind Force (N)
40 m2

25. Activity – Own designs!
Force (N) = Pressure (N/m2)
x Area (m2) x Safety Factor
1 2
Safety Factor of 1.2
Pressure (N/m2) =
0.6 x windspeed2
3
4