Liquefaction?

[Rabbit12]

I was reviewing a geotech report for a project I'm working on. It has this statement:

Liquefaction: Unlikely, even with the shallow water table, as native soils are cohesionless and reside in a relatively dense natural state.

Did I miss some recent development? I recall liquefaction being an issue in saturated clean sands.......

The report goes on to say that although the site is seismically active and the water table is relatively shallow in areas of lower elevation, the sands are poorly graded and in a medium-dense condition, and have experienced prior seismic shaking.

Would previous exposure to shaking effect the tendency to liquefy?

 

[Ron]

The higher the density of saturated sands, the lower the liquefaction potential, but it can still happen depending on the intensity of the vibration.

 

[Okiryu]

If I remember correctly, in Christchurch (New Zealand), liquefaction occurred again in same areas previously affected by liquefaction during the 2010-2011 earthquakes.

 

[Retrograde]

The fact that the soil is described as medium-dense means it is unlikely to be susceptible to liquefaction. Generally it only occurs in loose sands.