The vibratory roller is most effective for compacting
- ACH
- BSWCorrect
- CCL
- DMH
Solution
Concept
Compaction Equipment for Granular Soil
Formula
No standard formula.
Step-by-step solution
1. Identify the soil type: Vibratory compaction is most effective for cohesionless, granular soils like well-graded sand (SW). 2. Eliminate cohesive soils: Clays and silts (CH, CL, MH) require kneading or impact action (e.g., sheepsfoot rollers). 3. Select option B (SW).
Explanation
Vibratory rollers work best on well-graded sand (SW) and other granular, non-cohesive soils. The rapid vibrations reduce friction between the soil particles, allowing them to shift, rearrange, and pack closely together into a denser structure.
Shortcut
Vibratory rollers Shake Sand (Vib-S-S) — vibrations work best on coarse, granular/cohesionless soils like Sand (SW).
Common mistake
A common mistake is confusing vibratory rollers with sheepsfoot rollers and choosing cohesive soils like highly plastic clay (CH) or low plasticity clay (CL), which require kneading action rather than vibration.
Correct answer: B) SW