Granular subbases for slabs on ground can be compacted with sheepsfoot rollers. True or False?

Granular subbases for slabs on ground can be compacted with sheepsfoot rollers. True or False?

• A. True
• B. False
• C. Sometimes
• D. Only with vibration

Answer: (B)

Granular subbases under slabs on grade are non-cohesive materials that densify mainly through vibration, not kneading. A sheepsfoot roller is designed to knead soils with some cohesion (like clays) and compacts by pressing the feet into the material. That kneading action isn’t effective for granular materials, which require rearrangement of particles through vibration to reach the desired density. So using a sheepsfoot roller on a granular subbase won’t achieve proper compaction. The best approach is to use a vibratory roller (such as a smooth-drum or pneumatic-tire roller) at the correct moisture content to attain the required density.

Granular subbases under slabs on grade are non-cohesive materials that densify mainly through vibration, not kneading. A sheepsfoot roller is designed to knead soils with some cohesion (like clays) and compacts by pressing the feet into the material. That kneading action isn’t effective for granular materials, which require rearrangement of particles through vibration to reach the desired density. So using a sheepsfoot roller on a granular subbase won’t achieve proper compaction. The best approach is to use a vibratory roller (such as a smooth-drum or pneumatic-tire roller) at the correct moisture content to attain the required density.