This video shows how a reinforced concrete beam fails when no shear reinforcement is provided.
Longitudinal steel bars have been provided to resist the tensile forces in the bottom of the beam due to bending (or flexure).
Rectangular steel links would normally be provided to resist the tensile forces in the beam due to shear.
In this video, however, shear links have not been provided. So, the beam experiences a sudden, brittle, shear failure as the applied load exceeds the shear capacity of the concrete.
Note how a diagonal crack forms suddenly between the left-hand support and the applied load. The graph shows how the beam experiences an instantaneous loss of strength as soon as the shear capacity of the concrete is exceeded.
This video will help students answer questions such as:
- What is reinforced concrete?
- What crack pattern would you expect to see on a simply-supported concrete beam where no shear reinforcement has been provided?
- Where does the reinforcement need to be positioned in a simply-supported beam to resist tension forces due to shear?
Shear Failure of a Simply Supported Concrete Beam by Think Up is licensed under a Creative Commons Attribution 3.0 Unported License.
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