What is a cantilever beam and how can we calculate its deflection?
You may have read our previous article about beams and their deflection. The article talked about deflection in general – what it is and how can it be determined. Now we’re going to dive a little deeper and focus on cantilever beams and their deflection.
What is a cantilever beam?
Cantilever beams are beams that are constrained at one end and free at the other. At the fixed, or restrained, end of the beam the slope and deflection must be zero. Deflection increases as we move towards the free end, with maximum deflection at the tip.
Some examples of cantilever beams in construction are:
Cantilever beams can be either end-loaded or uniformly loaded. There’s a great video here giving us details on the slope and deflection along the beam.
End-loaded cantilever beams
Here the load is applied at a single point on the beam. The first diagram below shows a cantilever beam with a deflected shape. The second diagram shows a cantilever beam carrying a point load at its free end.
Uniformly loaded cantilever beams
These types of beams have the force acting uniformly along its length. An example of a cantilever beam carrying uniformly distributed load (UDL) would be a balcony.
The diagram below shows a schematic representation of this type of cantilever beam.
Standard data table for cantilever beam deflection and slope.
The most practical and fastest way to calculate the deflection and slope of a beam is to use standard tables. There are quite a few beam deflection tables that can be used.
For a cantilever beam subjected to a single type of loading, for example a point or concentrated load, uniformly distributed load, deflection and slope can be determined using the formulae in the table below:
Interested in our courses?
Interested in civil engineering? Find out more about all the civil engineering courses we have available by clicking here.
Diploma in Sustainable Construction
Diploma in Structural Engineering
Diploma in Building and Construction Engineering
Higher International Certificate in Civil Engineering
Higher International Diploma in Civil Engineering
Alternatively, you can view all our online engineering courses here.
Recent Posts
Best practice standards used in the construction industry
Best practice standards used in the construction industry. If you’ve read our article on the civil engineering code of conduct, you’ll be familiar with some best practices in construction projects. In this article we’re going to focus on the best practice standards used in the construction industry. What are best practices? In civil engineering and […]
Civil Engineering Code of Conduct
Civil Engineering Code of Conduct If you’ve read our article on sustainable design in a construction project you’ll already be familiar with some ethics around construction. However, there’s a lot more to it than that, and we’ll find out some of the considerations an engineer must think about in this article. Business ethics for engineers […]
What is sustainable design in a construction project?
What is sustainable design in a construction project? Before we can understand sustainable design, we first need to understand sustainable development. Sustainable development The World Commission on Environment and Development defines it as “a strategy that…meets the needs of the present generation without compromising the ability of future generations to meet their own needs”. However, […]