Red Seal Ironworker (Generalist) Practice Exam

What does the term cantilever refer to in structural frameworks?

1. A beam anchored at both ends

2. A beam fixed in the middle

3. A projecting beam anchored at only one end

4. A beam that is mobile

The correct answer is: A projecting beam anchored at only one end

The term cantilever refers to a projecting beam that is supported at only one end. This structural design allows the beam to extend outwards without any additional support beneath it, which can be beneficial for creating overhangs or balconies in building construction. Cantilevers work by transferring the load from the extended portion back to its support, which is typically at the anchored end. This unique structural capacity means they can bear significant loads while minimizing the need for additional supports, thus allowing for more open spaces beneath. In contrast, a beam anchored at both ends does not exhibit the same advantages as it is fully supported and lacks the projection characteristic of a cantilever. A beam fixed in the middle suggests a different structural behavior that does not define a cantilever. Lastly, a mobile beam implies movement which is not a characteristic of cantilever structures, which are designed to be stable in their position once installed. All these aspects highlight how cantilevers play a specific and critical role in framing and structural engineering.