Long-lasting Post-quake Deformation Buildups in the Grounds that Spread Laterally in Recent Earthquakes

Abstract In seismically active regions, loose saturated sandy soils are prone to liquefaction. A strong ground shake can create considerable excess pore water pressures in these soils and temporarily decreases the effective stress and shear strength, leading to strength loss, excessive ground settlements, and lateral spreading. Not to mention the immediate ground deformation, post-seismic settlement, and lateral ground spreading often build up slowly and steadily, causing problems for quick rehabilitations to lifeline facilities, etc. However, this long-lasting post-quake deformation buildup has caught less public attention, and quantitative pieces of evidence are less numerous than those about immediate impacts. This article reviews case histories, showing quantitatively that liquefied soils can remain soft for months.