I spent the first ten years of my academic career at Lehigh University, then 23 years of my working life at Purdue University in West Lafayette, IN. My early research was on the full scale testing of structural connections and plastic design in steels at the Fritz Engineering Laboratory at Lehigh University with its world famous five million pound universal testing machine. It was at Lehigh University that I made the major part of my contributions to the theory of plasticity and to its application to the design of engineering structures and components. The pioneering work was summarized in the classical two-volume book entitled "Theory of Beam-Columns" in 1976-77.

Combining solid mechanics with mathematical theory of plasticity, I started the pioneering work in applying the theorems of limit analysis to predict the load-carrying capacity of foundations, slope stability and earth pressures problems which formerly were beyond the scope of engineering practice. The merit of limit analysis as applied to soil mechanics lies in the fact that geotechnical engineers can now make original, practical and safe decisions on the design of complex load-bearing estimates on the basis of relatively simple calculations. The pioneering work was published in the milestone book entitled "Limit Analysis and Soil Plasticity" in 1975.

In my later years at Purdue, I became active in a field now known as "Advanced Analysis", which attempts to bridge the gap in design between using elastic analysis for a structural system while sizing up the structural members with an inelastic analysis through the use of the so-called "The Effective Length Factor", or simply known as the K-factor design. as popularly used in engineering practice. Research works on advanced analysis are now well developed, verified and coded by the American Institute of Steel Construction’s 2005 AISC Specifications as well as others around the world.