Concrete's tensile strength typically ranges from 300 to 700 psi (2 to 5 MPa), averaging about 10% of its compressive strength.
Concrete is significantly stronger in compression than in tension. While it excels at resisting pushing forces, its ability to withstand pulling forces is quite limited.
Based on studies, the tensile strength of traditional concrete generally falls within a specific range:
- Range: 300 to 700 psi
- Equivalent Metric Range: Approximately 2 to 5 MPa (Megapascals)
This relatively low tensile capacity means that concrete structures often require reinforcement (like steel rebar) in areas where tension forces are anticipated, such as beams or slabs.
Relationship to Compressive Strength
An important insight from studies is the comparison between tensile and compressive strength:
- On average, the tensile strength of concrete is only about 10% of its compressive strength.
For example, if concrete has a compressive strength of 4000 psi, its tensile strength would likely be around 400 psi. This stark difference highlights why compression is concrete's primary load-bearing mechanism.
Flexural Strength
Related to tensile strength is flexural strength, which describes concrete's resistance to bending. Bending introduces both compressive and tensile stresses within a material. Because concrete is weak in tension, its flexural strength is also limited by its tensile capacity. Flexural strength is often a critical consideration in pavement design and beams, as it establishes the ability of concrete to withstand bending forces.
Here's a summary of the typical tensile strength ranges:
| Measurement Unit | Typical Range |
|---|---|
| Pounds per Square Inch (psi) | 300 - 700 psi |
| Megapascals (MPa) | 2 - 5 MPa |
Understanding concrete's low tensile strength is fundamental in structural engineering, dictating the need for reinforcement in many applications to prevent cracking and failure under tensile loads.
