Research reveals new insights into soil liquefaction during earthquakes
Soil liquefaction is a natural hazard that commonly occurs during earthquakes and is one of the most catastrophic earthquake-related phenomena.
During and after liquefaction, buildings and infrastructures sink, float and tilt, ground might spread and crack, settle, or initiate a landslide. Liquefaction damage often leads to extensive human casualties, destruction of lifelines, and economic losses that may result in the complete abandonment of formerly inhabited areas, posing a significant challenge to community resilience.
In a new study, the conventional understanding of soil liquefaction is being challenged, significantly reshaping our comprehension of earthquake-related soil deformation. Traditionally, soil liquefaction has been linked to undrained conditions near earthquake epicenters, but this research reveals that liquefaction can take place under drained conditions, even at considerably lower seismic-energy density levels. This discovery sheds new light on far-field liquefaction events that have long perplexed scientists. The study highlights how seismic shaking, even in drained conditions, triggers interstitial fluid flow within the soil, leading to the accumulation of excess pore pressure gradients and the subsequent loss of soil strength. Drained liquefaction unfolds rapidly, guided by the propagation of a compaction front, with its speed determined by the rate of seismic-energy injection. These findings mark a profound shift in our understanding of soil liquefaction, empowering us to conduct more precise assessments of its potential and associated risks, ultimately bolstering efforts in earthquake engineering and preparedness.
New research conducted by Dr. Shahar Ben-Zeev and Prof. Einat Aharonov at The Hebrew University of Jerusalem and the University of Strasbourg, Prof. Liran Goren of Ben-Gurion University of the Negev, and Prof. Renaud Toussaint from the University of Strasbourg has unveiled a remarkable discovery – liquefaction can occur under drained conditions even at remarkably low seismic-energy density levels.
