Dr. Braja Das is dean emeritus of the College of Engineering and Computer Science at California State University, Sacramento. He received his M.S. in civil engineering from the University of Iowa and his Ph.D. in geotechnical engineering from the University of Wisconsin. He is the author of several geotechnical engineering texts and reference books as well as more than 300 technical papers in the area of geotechnical engineering. His primary areas of research include shallow foundations, earth anchors and geosynthetics. Dr. Das is a fellow and life member of the American Society of Civil Engineers, life member of the American Society for Engineering Education and an emeritus member of the Stabilization of Geomaterials and Recycled Materials of the Transportation Research Board of the National Research Council. He has received numerous awards for teaching excellence, including the AMOCO Foundation Award, the AT&T Award for Teaching Excellence from the American Society for Engineering Education, the Ralph Teetor Award from the Society of Automotive Engineers and the Distinguished Achievement Award for Teaching Excellence from the University of Texas at El Paso.


Dr. Khaled Sobhan is a Professor of Civil, Environmental and Geomatics Engineering at Florida Atlantic University. He received his M.S. degree from The Johns Hopkins University, and his Ph.D. from Northwestern University, both in the area of Geotechnical Engineering. His primary research areas include ground improvement, geotechnology of soft soils, experimental soil mechanics, and geotechnical aspects of pavement engineering. Dr. Sobhan served as the Chair of the Chemical and Mechanical Stabilization committee (AFS90) of the Transportation Research Board (2005-2011), and co-authored the TRB Circular titled Evaluation of Chemical Stabilizers: State-of-the-Practice Report (EC086). He is currently serving as an Associate Editor of ASCE Journal of Materials in Civil Engineering, and on the editorial boards of the ASTM Geotechnical Testing Journal, Geotechnical and Geological Engineering (Springer, The Netherlands), and International Journal of Geotechnical Engineering. Dr. Sobhan is a recipient of the distinguished Award for Excellence and Innovation in Undergraduate Teaching (2006), and the Excellence in Graduate Mentoring Award (2009) from Florida Atlantic University. He has authored/co-authored more than 100 technical articles and reports in the area of geotechnical engineering.