How does the addition of fibers to concrete improve its properties?

The addition of fibers to concrete significantly enhances its properties, primarily by improving tensile strength and reducing the occurrence of cracking. Fibers, which can be made from various materials such as steel, glass, or synthetic polymers, are uniformly dispersed throughout the concrete mixture. This reinforcement helps to bridge the cracks that may form due to tensile stresses, thus preventing the propagation of cracks and mitigating crack formation during and after the curing process.

Improving tensile strength is critical because concrete is inherently weak in tension. When fibers are included, they help resist tension forces that occur under applied loads. This leads to a more durable and resilient concrete structure, particularly essential in applications subject to dynamic loads, impact, or seismic activity. The reduction in cracking not only increases the longevity of the concrete but also enhances its aesthetic appeal and reduces maintenance costs.

The other options do not accurately reflect the main benefits of fiber reinforcement in concrete. While adding fibers may slightly influence other properties, the key advantages are primarily related to tensile strength and crack resistance.