Research Profile

Municipal Solid Waste and Landfill Engineering

Professor Kavazanjian’s current research interests include the mechanical properties of municipal solid waste, seismic design of waste containment systems, geotechnical earthquake engineering for highways, and microbiological improvement of the physical properties of soil. Work is now being completed on a multi-year collaborative research project sponsored by the National Science Foundation on the Static and Dynamic Properties of Municipal Solid Waste with the University of California at Berkeley and the University of Texas at Austin. ASU’s contribution to the research project include static and cyclic testing on reconstituted specimens of MSW using unique 450-mm diameter testing equipment in the E.M. Hoque Geotechnical Laboratory at ASU. Testing conducted at ASU is looking at the influence of initial density and waste composition on mechanical behavior. Following completion of this collaborative effort, the next phase of the research effort will use the results of the testing program to evaluate the Performance of Geosynthetic Liner Systems at MSW Landfills Subject to Seismic Loading.

Figure 1: Large (454 mm) Diameter Direct Shear Device

Figure 1: Large (454 mm) Diameter Direct Shear Device

Geotechnical Earthquake Engineering

Professor Kavazanjian and ASU have recently been engaged as co-principal investigator with Parsons Brinckerhoff to prepare a training course for the Federal Highway Administration on Geotechnical Earthquake Engineering for Transportation Structures and Other Features. Development of the course will include preparation of a comprehensive reference manual that updates and expands the current manual (shown below) co-authored by Professor Kavazanjian in 1998 to include LRFD (Load and Resistance Factor Design) Concepts as well as coverage of buried structures (tunnels and culverts).

Figure 2: FHWA Reference Manual on Geotechnical Earthquake Engineering

Figure 2: FHWA Reference Manual on Geotechnical Earthquake Engineering

Microbiological Improvement of Soil

With support from the National Science Foundation, Professor Kavazanjian has recently initiated a research program on Microbiological Improvement of the Physical Properties of Soil. This research program is looking at three different mechanisms for microbiological improvement: mineral precipitation, mineral transformation, and biopolymer growth. Microbiologically-induced carbonate precipitation using ureolysis is being studied by several research groups in the US and abroad. Research at ASU is focusing on inducing carbonate precipitation through denitrification and sulfate reduction mechanisms. If successful, this technique would have broad application in geotechnical practice for seismic hazard (liquefaction) mitigation, foundation design, and underground construction. Work at ASU is also looking at mineral transformation mechanisms, including microbially-induced reduction of iron as a means of mitigating swell potential in expansive soils. Preliminary bench scale testing indicates microbial reduction of FE (3+) to FE (2+) may significantly reduce the expansion potential of iron-rich clays. Transfer of this technology from bench-scale to the field would provide a sustainable means of mitigation for what remains the single largest source of monetary loss due to natural hazards in the US on an annual basis (swelling soils).

Impact of Microbial Treatment on the Index Properties of a Natural Soil

Impact of Microbial Treatment on the Index Properties of a Natural Soil