The most suitable equipment for compaction of cohesive soils is 

Explanation:

Compaction of Cohesive Soils

Cohesive soils, such as clay, are characterized by their fine-grained structure and ability to retain moisture. Proper compaction of cohesive soils is critical to achieve desired density and strength. The choice of equipment for compaction depends on soil type and moisture content. Among the available options:

1. Smooth-Wheeled Roller

   • Suitable for granular soils like sand and gravel but ineffective for cohesive soils.

   • Does not provide adequate kneading action, which is required for cohesive soils.

2. Vibratory Roller

   • Effective for compacting non-cohesive soils like sand due to vibrations, but less effective for cohesive soils.

   • Does not provide sufficient kneading action required for clayey soils.

3. Sheep-Footed Roller (Correct Answer)

   • Most suitable for cohesive soils as it provides kneading and pressure action, which is essential for compaction.

   • Its projections (feet) penetrate the soil, facilitating uniform compaction and removal of air voids.

   • Highly effective in achieving desired density in fine-grained, cohesive soils.

4. Tamper

   • Effective for small-scale compaction tasks, but not suitable for large areas or for cohesive soils requiring deep compaction.

   • Primarily used for compacting confined spaces or repairing small patches.

Conclusion:

The most suitable equipment for compaction of cohesive soils is the sheep-footed roller due to its kneading action, which ensures uniform compaction and removal of air voids.