The result of Vee-Bee test is expressed in terms of ……………
Correct Answer: A. s
📚 Detailed Explanation: Vee-Bee Test and Its Units
The Vee-Bee consistometer test (IS 1199) is designed for very stiff concrete where the slump test is unreliable. It measures the time required for a standard amount of vibration energy to remould a concrete specimen.
Why A (s = seconds) is correct: The Vee-Bee test procedure: place concrete in slump cone inside a cylindrical container on a vibrating table; remove cone; start vibration and timer; stop timer when concrete completely fills the cylinder. The result = time in seconds. More seconds = stiffer mix = lower workability. Options B (m = metres), C (N/mm² = stress), D (kg = mass) are all wrong units for a time measurement.
Vee-Bee Time vs. Workability
| Vee-Bee Time (s) | Workability |
|---|---|
| >20 s | Very low |
| 10–20 s | Low |
| 5–10 s | Medium |
| 2–5 s | High |
- Vee-Bee result = seconds. Higher time = lower workability.
- Best suited for stiff mixes: roller-compacted concrete, precast, dry lean mixes.