Liquefaction and Ground Failure During the 1998 Adana (Turkey) Earthquake and Lab Model Simulations

Although the June 27, 1998 Adana (Turkey) earthquake event was moderate in magnitude (5.9 on the Richter scale) and in the resulting damage, it contains significant valuable data for geotechnical earthquake engineering. The coincidence of the earthquake epicenter and the fault with a very vulnerable geological surface formation - thick alluvial deposits of Ceyhan River containing loose sand-silt layers, accounted for substantial thickness and area1 distribution of liquefied sediments. Consequently, liquefaction associated ground deformations such as lateral spreading, flow failures, ground fissures and extensional cracking, sand boils, ground subsidence and slope failures were widespread. This paper presents and analyses the liquefaction and associated ground deformations observed during this earthquake. Field data on the occurrence of liquefaction-induced ground failures are used in conjunction with laboratory small-scale model testing results to help to improve our understanding of the mechanisms of generation of several forms of liquefaction-induced ground failure. In this context, valuable observations were made particularly for the sand boiling mechanisms