What is the primary function of welded wire reinforcement in slabs-on-grade that are considered unreinforced?

What is the primary function of welded wire reinforcement in slabs-on-grade that are considered unreinforced?

• A. Keep cracks tightly closed.
• B. Increase the slab's load-bearing capacity significantly.
• C. Improve surface finish.
• D. Prevent any cracking from occurring.

Answer: (A)

Welded wire reinforcement in slabs-on-grade that are treated as unreinforced is placed to control crack width, not to carry a lot of load. As the concrete dries and as temperatures change, hairline cracks form. The mesh acts as a bridge across those cracks, restraining them and keeping the openings small so cracks stay tightly closed. This improves durability and surface appearance to some extent, but it does not prevent cracking entirely or dramatically boost the slab’s load-carrying capacity.

Welded wire reinforcement in slabs-on-grade that are treated as unreinforced is placed to control crack width, not to carry a lot of load. As the concrete dries and as temperatures change, hairline cracks form. The mesh acts as a bridge across those cracks, restraining them and keeping the openings small so cracks stay tightly closed. This improves durability and surface appearance to some extent, but it does not prevent cracking entirely or dramatically boost the slab’s load-carrying capacity.