Long term settlement is typically less in which material compared to clay?

Long-term settlement is influenced by a material's compressibility and the way it consolidates over time. In this context, sand is typically seen as having lower long-term settlement compared to clay.

Sand consists of coarser particles that have larger void spaces and less surface area compared to clay particles. This results in a lower ability to retain water and a quicker drainage response when subjected to load. As a result, sand generally experiences less consolidation under load, leading to less long-term settlement.

In contrast, clay is a fine-grained material that tends to retain water and is highly compressible. When loads are applied, clay undergoes significant consolidation as pore water is expelled, which can lead to substantial long-term settlement.

While gravel may also show less settlement compared to clay, sand is specifically less compressible due to its physical characteristics, making it the most suitable answer to this question.