What happens to saturated soil during liquefaction?

During liquefaction, saturated soil experiences a phenomenon where it temporarily loses strength and stiffness, which can occur during seismic events or sudden load applications. When the soil is saturated, the pore water pressure increases significantly due to the vibration caused by an earthquake or similar disturbance. This increase in pore water pressure effectively reduces the effective stress in the soil, leading to a condition where the soil behaves more like a liquid than a solid.

In this state, the soil particles become unable to maintain their inter-particle friction and cohesion, resulting in a drastic decrease in the soil's ability to support loads. This can lead to dangerous situations where buildings and structures may settle, tilt, or even collapse as the foundation becomes unstable. The phenomenon highlights the critical importance of understanding the behavior of saturated soils in geotechnical engineering, particularly in seismic areas.

The other options do not accurately depict the behavior of saturated soils during liquefaction, as liquefaction is characterized by a loss of strength rather than an increase in cohesiveness, elasticity, or conversion into solid rock.