Special Research Seminar Held at UFAZ on the Occasion of Earth Day

A seminar titled “The Mechanics of Seismic Drained Soil Liquefaction: A Numerical, Theoretical, and Experimental Study” was delivered at UFAZ by Dr. Renaud Toussaint, invited professor at UFAZ and senior researcher at the University of Strasbourg and the French National Centre for Scientific Research (CNRS).

Dr. Toussaint’s research focuses on understanding how Earth systems function, particularly the interactions between fluids and solid materials, and the links between different physical processes. In his Earth Day lecture, he explained how loose, water-saturated soils can behave like a liquid during an earthquake, losing their strength and ability to support structures - a process known as soil liquefaction. This phenomenon can cause buildings and infrastructure to sink or collapse.

The seminar highlighted that soil liquefaction primarily occurs in earthquake-prone areas with loose, wet soils. It was explained how seismic shaking can significantly reduce the soil’s load-bearing capacity. Liquefaction is often compared to quicksand, as the ground temporarily loses its solid structure and behaves like a fluid.

The mechanics of seismic liquefaction under drained conditions are explored using simulations that couple fluid and granular media with controlled laboratory experiments. The study identifies how the strength and characteristics of seismic shaking, the spatial arrangement of soil grains, and the distribution of water within the soil affect the potential for liquefaction.

Dr. Toussaint’s interdisciplinary approach provides an exemplary model for students and researchers in the fields of geology, civil engineering, and environmental sciences.