Current Research (2008)

• A Micromechanical Investigation of Material Instability in Particulate Media (Bardet) This research investigates the microscopic origins of shear band instability and liquefaction instability in granular media. Our methodology combines computational micromechanics and laboratory experiments. The research objectives are to improve our methods of computational micromechanics, examine the formation of shear bands, investigate the effects of grain rotation on shear strength and shear bands, to study liquefaction instability, and to explore the macro-micro mechanics transition, relevant to material instability. Solving these fundamental research problems will enhance our understanding of instability in particulate media.
• Analysis of Ground Displacement and Failure in the Van Norman Facilities after the 1994 Northridge Earthquake (Bardet). The University of Southern California (USC) coordinates the research on the ground deformation and failure in the Van Norman Complex after the 1994 Northridge Earthquake. This research regroups USC, Case Western Reserve University, Dames & Moore, Cornell University, and the Los Angeles Department of Water and Power. The objective of this collaborative research is to analyze the strong-motion recordings in the Van Norman Complex, to measure the permanent ground displacements of the general area and those of the Los Angeles Reservoir, and Upper and Lower San Fernando Dams by aerial and land surveys, to determine the material properties of hydraulic fills, and to investigate the validity of methods for nonlinear dynamic analysis based on well-documented field cases.
• Investigation of Liquefaction-Induced Lateral Ground Deformation during Earthquakes (Bardet). Liquefaction-induced ground deformation has amplitudes ranging from a few centimeters to ten meters and more. It caused substantial damage to lifelines and pile-foundations of buildings and bridge piers along the Kobe shoreline during the 1995 Hyogoken Nanbu, Japan, earthquake. The research objective is to develop probabilistic models of liquefaction-induced ground displacement useful for estimating the cost of damage and repair to lifeline networks during future earthquakes.
• Synthetic Surfaces (Bardet). The potential application of biopolymer technology for the construction of impervious barriers, using silty soils, is being investigated. Laboratory experiments to date, demonstrate that the permeability of silty soils can be reduced by a factor of 100 or greater. This can be done by either mixing commercially available biopolymers such as xanthan gum with the soil matrix or slime-forming microorganisms with the soil matrix to produce biopolymers. Experimental results indicate that the soil shear strength is also increased by up to 50 percent. The practical application of the technology to construct impervious landfill covers is presently being evaluated.
• Research Before 2008
   

The Faculty

Selected Publications