NASCLA Accredited Commercial General ContractorMasonryEasy
A masonry contractor is preparing to construct a load-bearing concrete masonry unit (CMU) wall that will be reinforced vertically. Which of the following is the primary purpose of filling the CMU cores with grout?
- ATo provide thermal insulation within the wall cavity, improving energy efficiency.
- BTo increase the aesthetic appeal of the wall by providing a uniform finish.
- CTo prevent water penetration through the block joints and enhance waterproofing.
- DTo bond the vertical reinforcement to the masonry and increase compressive strength.
Show answer & explanationAnswer & explanation
Correct answer: D. To bond the vertical reinforcement to the masonry and increase compressive strength.
Grout is specifically designed to fill the voids in masonry units, bonding with reinforcement and contributing significantly to the structural integrity and compressive strength of the wall. This is distinct from mortar, which is used for bonding units together.
Why the other options are wrong
- A. While some grouts may offer minimal insulation, it is not their primary purpose; insulation is typically provided by other materials.
- B. Grout is not primarily used for aesthetic finish; mortar or other finishes serve this purpose.
- C. Grout helps with structural integrity, but waterproofing is achieved through proper flashing, weep holes, and sealant application.
Grout in Reinforced Masonry
Grout is a cementitious mixture used to fill the cores of hollow masonry units and the spaces between masonry and reinforcement, bonding the components together to form a composite structural element.
- Bonds reinforcement to masonry units.
- Increases compressive strength of the wall.
- Ensures composite action of the reinforced masonry.
Memory trick: Grout Gives Great Grip to Reinforcement