Which statement best describes rebars?

Which statement best describes rebars?

• A. Wooden boards used to separate forms
• B. Concrete blocks used in CMU
• C. Steel reinforcing bars used to increase tensile strength
• D. Insulation material

Answer: (C)

Rebars are steel reinforcing bars embedded in concrete to increase its tensile strength. Concrete is strong in compression but weak in tension, so the steel reinforcement carries the higher tensile stresses that occur when a structure bends or cracks, helping the member resist cracking and carry loads more effectively. The steel bonds with the surrounding concrete, especially where the bar has ridges or deformations, and is placed in the formwork before the concrete is poured so the two materials act together as a single composite element. They are used in slabs, beams, columns, and footings, sized and spaced according to structural design, and may have protective coatings to resist corrosion. Wooden boards used to separate forms are part of formwork, CMU blocks are masonry units, and insulation material serves thermal resistance, not reinforcement.

Rebars are steel reinforcing bars embedded in concrete to increase its tensile strength. Concrete is strong in compression but weak in tension, so the steel reinforcement carries the higher tensile stresses that occur when a structure bends or cracks, helping the member resist cracking and carry loads more effectively. The steel bonds with the surrounding concrete, especially where the bar has ridges or deformations, and is placed in the formwork before the concrete is poured so the two materials act together as a single composite element. They are used in slabs, beams, columns, and footings, sized and spaced according to structural design, and may have protective coatings to resist corrosion. Wooden boards used to separate forms are part of formwork, CMU blocks are masonry units, and insulation material serves thermal resistance, not reinforcement.