What is the purpose of using aluminium or glass strips in terrazzo flooring panels?
- AProvide structural support to the flooring.
- BEnhance the aesthetic appeal of the flooring.
- CCreate size and shape separation between different colours or patterns of terrazzo materials.
- DPrevent cracking and ensure uniform thickness of the terrazzo flooring.Correct
Solution
Concept
Dividing strips in terrazzo flooring control cracking caused by drying shrinkage and thermal expansion/contraction.
Step-by-step solution
1. Understand the nature of terrazzo flooring, which is laid in panels using cementitious or resinous matrices. 2. Recognize that large areas of cement-based toppings are susceptible to volumetric changes (shrinkage and thermal movement). 3. Aluminium or glass strips are embedded into the mortar bed to divide the floor into smaller panels, accommodating these movements and preventing random cracking. 4. Therefore, their primary technical purpose is to prevent cracking and ensure structural/dimensional integrity of the panels.
Explanation
Aluminium, brass, or glass strips (known as dividing strips) are used in terrazzo flooring to act as expansion joints. They prevent shrinkage cracks during the curing process and control cracking due to thermal movements, while also helping to maintain a uniform thickness and level of the panels.
Why the other options are wrong
A: Strips do not provide structural support to the slab. B: While they enhance aesthetics by creating patterns, their primary functional purpose in construction is crack prevention. C: Separation of colours can be a secondary outcome, but the main technical reason is crack control.
Shortcut
Remember 'strips = control joints = crack prevention'.
Common mistake
Confusing the decorative appearance (option B) with the primary structural/functional purpose, which is crack prevention.
Correct answer: D) Prevent cracking and ensure uniform thickness of the terrazzo flooring.