Which of the following is a benefit of using fiber-reinforced concrete?

• A. Improved crack resistance
• B. Increased permeability
• C. Reduced durability
• D. Longer setting time

Answer: (A)

Fiber reinforcement works by bridging cracks as they form, so the concrete can carry load even after cracking begins. The fibers extend across developing cracks and transfer some of the stress, which slows crack opening and stops cracks from propagating as easily. This action makes the concrete tougher and more resistant to crack growth, especially under tensile stresses from drying shrinkage, temperature changes, or loading. In practical terms, you get smaller crack widths, better post-crack strength, and improved durability in real-world conditions. The other options aren’t benefits typically provided by adding fibers: permeability isn’t something fibers are known to increase, setting time isn’t a primary advantage of fiber reinforcement, and fibers generally don’t reduce durability—in many cases they enhance it by limiting crack development.