Effects of earthquake-induced liquefaction: Integrated research tools towards optimum reduction of society vulnerability

Earthquake-induced liquefaction is widely recognised as a serious hazard threatening modern societies. Indeed, even if the death toll is usually smaller than with other seismic phenomena, such as tsunamis, the economic and social distress and the extent of post-earthquake recovery caused by liquefaction are often more severe. This paper describes the research carried out at the University of Coimbra, Portugal, with its international partners, focusing on the assessment and mitigation of earthquake-induced liquefaction hazards at different levels and using different tools to reduce more effectively society's vulnerability to this phenomenon. Element testing has been combined with centrifuge modelling to assess the basic soil behaviour and the actual mechanisms governing field performance of geotechnical structures. Numerical modelling is used to extend experimental findings and to predict more accurately liquefaction effects, so that the principles of performance-based design can be used in current design practice. New energy-based design approaches and innovative planning tools for transportation infrastructures considering liquefaction hazards at a macro scale have been developed, allowing for better consideration of liquefaction effects in informed decision-making