Construction Methods and Materials Flashcards
7 cards from real CITB practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Construction Methods and Materials flashcards as text
What is the primary advantage of using fly ash as a partial cement replacement in concrete?
Answer: It improves workability and reduces heat of hydration
Fly ash improves concrete workability due to its spherical particles and reduces heat of hydration, lowering the risk of thermal cracking in mass pours.
In masonry construction, what is the purpose of a control joint?
Answer: To allow for planned cracking due to thermal or shrinkage movement
Control joints are intentional planes of weakness that allow masonry to crack in a controlled, predictable location due to thermal expansion and contraction or shrinkage.
Which roofing system uses a continuous membrane adhered or mechanically fastened to the roof deck?
Answer: Single-ply membrane (TPO/EPDM)
Single-ply membrane systems like TPO and EPDM consist of a single continuous sheet installed over the roof deck, either adhered, ballasted, or mechanically fastened.
What does the term 'pile driving refusal' mean on a construction site?
Answer: The point at which a pile cannot be driven further because it has reached load-bearing soil or rock
Refusal occurs when a pile meets resistance so great that it cannot be driven further, typically indicating it has reached adequate bearing capacity.
In concrete formwork design, what is the primary factor determining the lateral pressure exerted on vertical forms?
Answer: The rate of concrete placement and concrete unit weight
Lateral pressure on formwork increases with faster pour rates and higher concrete unit weight, as the fluid concrete acts hydrostatically before it sets.
Which type of floor system is most commonly used to achieve long spans with minimal structural depth in commercial construction?
Answer: Composite steel deck with concrete topping
Composite steel deck with concrete topping combines steel's tensile strength with concrete's compressive strength, enabling long spans with a shallow overall floor depth.
What is the key difference between 'cut and fill' and 'balanced earthwork' on a grading project?
Answer: Balanced earthwork means excavated (cut) material equals the fill needed, minimizing import/export
Balanced earthwork occurs when the volume of material cut from high areas equals the volume needed to fill low areas, eliminating costly material hauling off-site or importing fill.