BeginnerTopic 2 of 112Civil & Structural
Building loads
Dead, live, wind, snow and seismic loads must be combined for design.
In depth
Structures resist dead load (self-weight and fixed items), live load (occupancy, furniture, traffic), wind, snow, earthquake, thermal, settlement and impact loads. Codes give characteristic values and combination factors, e.g. 1.2D+1.6L. Loads are applied as point, line, area or dynamic effects.
Key points
- Load combinations in codes
- Tributary area for area loads
- Self-weight of concrete about 25 kN/m³
ExampleAn office floor may be designed for 3 kN/m² live load plus its own dead weight.
What is Building loads?
Dead, live, wind, snow and seismic loads must be combined for design.
Why is it important to understand building loads?
Structures must survive several kinds of load at once, so knowing each load type and how to combine them prevents under-design.
What is the difference between dead and live loads?
Dead loads are the permanent weight of the structure and fixed finishes. Live loads are variable, such as occupants, furniture and vehicles.
Why are loads combined?
Codes require load combinations, since the worst case often comes from several loads acting together rather than one alone.
How is Building loads used in practice?
Typical applications include calculating the design load on a warehouse roof in a snowy region, checking a multi-storey building against wind and earthquake forces and sizing a floor for people, furniture and equipment.
What should I learn before Building loads?
Study "Role of civil engineering" first (topic 1 of 112 in Civil & Structural). It covers the groundwork this topic builds on.
What are the key points of Building loads?
Load combinations in codes. Tributary area for area loads. Self-weight of concrete about 25 kN/m³.
Can you give an example of Building loads?
An office floor may be designed for 3 kN/m² live load plus its own dead weight.
What comes after Building loads?
The next topic is "Load paths", which builds directly on this one.
How difficult is Building loads?
It is classed as Beginner in Civil & Structural (topic 2 of 112). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.