This paper describes a number of case studies by using numerical procedures conducted by the author and his co-workers over a number of years. The case studies involve a wide range of static and dynamic stress-deformation, seepage and stability, and consolidation problems. The numerical procedures use simple linear and nonlinear elastic models, to advanced but simplified hierarchical plasticity based models for geologic materials and interfaces/joints. The evolution from the use of simple to advanced models is guided by the realization that it is essential to employ models that are capable of handling the complexities in geotechnical systems. In addition to use of the conventional and empirical methods, it is advisable to develop and utilize improved and simplified techniques based on basic principles of mechanics. This approach can allow the geotechnical engineer access to models and procedures towards improved and rational solutions for case studies and for practical applications
