Physical Modelling of Earthquake-induced Liquefaction on Uniform Soil Deposit and Settlement of Earth Structures

Abstract

Earthquake-induced liquefaction has been known as a complex and challenging topic in the field of geotechnical engineering. The phenomenon could bring catastrophic damage as has been seen from the past with severe damage seen on the ground and various structures such as buildings, earth structures, and lifelines. The occurrence of liquefaction is caused by the loss of strength and stiffness of the cohesionless saturated soils due to the rapid dynamic loads from the earthquake. The loss of strength and stiffness of the soil could lead to the failure of the foundation ground and structures placed above it. In order to analyze and observed the earthquake-induced liquefaction phenomena, physical modelling subjected to geotechnical centrifuge was conducted in this study. Embankment lies on liquefiable foundation ground was modelled by the means of physical modelling and subjected to the earthquake motion of The 2011 Tohoku Earthquake retrieved from K-Net Mito stations. Geotechnical centrifuge test with 50 g of centrifugal acceleration was conducted in order to create the actual fields conditions. The behaviour of the model was observed using sensors for acceleration, pore pressure, and displacement. The study aims to understand the liquefaction phenomena, mechanism and consequences through physical modelling and laboratory testing. The test shows that the liquefaction-induced damages to the foundation ground and the embankment as shown from the visual assessment and data obtained from the test. Liquefaction manifestation could be seen from the rapid development of excess pore water pressure on the foundation ground, lateral spreading, and settlement and deformation of the embankment.