NASCLA Accredited Commercial General ContractorConcreteMedium
A concrete slab is being finished, and the crew is performing bull floating after screeding. What is the primary purpose of bull floating the concrete surface?
- ATo embed coarse aggregate, remove minor imperfections, and bring cement paste to the surface.
- BTo cut off high spots and fill in low spots, achieving the final levelness.
- CTo create a smooth, hard, and dense surface for high wear resistance.
- DTo create a non-slip, textured finish for pedestrian traffic.
Show answer & explanationAnswer & explanation
Correct answer: A. To embed coarse aggregate, remove minor imperfections, and bring cement paste to the surface.
Bull floating is performed after screeding to embed aggregate particles slightly below the surface, remove minor surface irregularities left by screeding, and bring a uniform layer of cement paste to the surface, preparing it for subsequent finishing operations.
Why the other options are wrong
- B. Cutting off high spots and filling low spots is the primary purpose of screeding, which occurs before bull floating.
- C. This describes the purpose of power troweling, not bull floating.
- D. Creating a non-slip, textured finish is achieved by brooming, not bull floating.
Bull Floating
A concrete finishing operation performed after screeding to level the surface, embed aggregate, and bring paste to the surface.
- Uses a long-handled float (bull float).
- Removes screed marks.
- Prepares surface for later finishing tools.
Memory trick: Screed to Level, Float to Smooth, Trowel to Harden, Broom to Grip.