The purpose of the book is to help practicing engineers learn to y Taguchi experimental design techniques through the use of ry, step-by-step applications of concepts, and an introduction he Qualitek-4. software. Common manufacturing floor language sed to make the book understandable by technicians, engineers, managers. Equations are reduced in the text to further litate understanding. The book accomplishes this task and is a readable book. The reader, however, should be alert for occasional graphical errors in the text and calculations, which are always obvious.

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Contamination of the groundwater regime and subsurface soils is one of the major problems that has arisen due to rapid industrialization. Spread of contaminants in the unsaturated soil strata, mainly close to the ground surface and lying above the water table, depends on the hydraulic conductivity of the soil. As such, estimation of unsaturated soil hydraulic conductivity becomes very important. However, it is quite difficult to estimate the same in a reasonable amount of time, due to the very low hydraulic conductivity of unsaturated soil. The potential of a geotechnical centrifuge for modeling various geoenvironmental engineering problems being very well established, an effort has been made to obtain the unsaturated state of a silty soil, starting from its saturated state, by centrifugation. The soil water characteristic curves obtained have been used for determining the unsaturated soil hydranlic conductivity.

Static and dynamic compression experiments were performed on concrete and granite specimens with various levels of induced damage. Damage was induced into the specimens by repeated impacts from a falling weight and quantified as a measure of damage crack surface area per volume using a statistical microscopy technique. The static experiments were performed following ASTM standard procedures. The static compressive strength of both materials decreased with increasing levels of damage. The reduction in strength is due to the induced damage causing the activation and propagation of failure cracks in the specimens. The dynamic experiments were conducted using a 50.5 mm diameter Split Hopkinson Pressure Bar. The undamaged dynamic compressive strengths of both the concrete and granite were approximately twice their static values at average strain rates of 380/s and 400/s, respectively. However, as the damage levels were increased, the dynamic compressive strength remained unchanged. For the dynamic experiments, the strain energy is stored in the specimen faster than the cracks can develop and coalesce to completely fail the specimen. Therefore, the relatively small amounts of induced damage did not affect the dynamic compressive strength.

The yielding phenomenon under cyclic loading has been investigated for low-carbon steel. Under various loading ratios, the surface state of the specimen was observed with the naked eye, using the Lüders band as an indicator for the yield point elongation. The stress-strain curve was measured simultaneously. The results show that both the surface states and the cyclic stress-strain characteristics vary depending on the load ratio. This makes it questionable to use the yield strength evaluated under monotonic loading to describe the mechanical properties of the specimen material for fatigue tests, though it is a prevailing practice recommended by ASTM. The result of this study also indicates that the Lüders band can be used as a smart sensor to investigate the yield phenomenon.