Papers by Keyword: Plane Strain Conditions

Abstract: The non-linear crack mechanics (NLCM) is a concept assuring the occurrence of the same phenomena in two cracked bodies under large scale yielding. It has been recognized that NLCM is effective in the cases of plane stress conditions. In this study, it was made clear that NLCM is effective not only in the case of plane stress condition but also in the case of plane strain condition.

Abstract: Biaxial compression model tests on rockmass containing intermittent joints under plane stress condition were carried out in this study, where the laser speckle photo technique was used for measuring the displacement field. The results obtained have indicated that the laser speckle method was effective and the measuring value was about 14% less than the measuring value of dial gauges. Based on the displacement field and the principal stress field which were measured by laser speckle photo technique, dial gauges and strain gauges, the angle of wing incipient crack, the evolution of stress field at the joint tip and the path of crack extension were deeply studied. The deformation and failure characteristics, including the fracture mechanism of rockmass, were also analyzed in this study.

Abstract: The effect of assumption of plane state of stress on the predictability of experimental results observed during the mode II stable crack growth (SCG) through 8 mm thick compact tension specimens (CTS) of a workhardening aluminum alloy (D16AT) has been studied. Experimental results include load-sliding displacement diagram, extent of SCG, crack front geometry and fracture surface fractographs. The experimental results show that the crack extends in its own plane, the fracture surface is flat, smooth and free of any shear lip. The crack front geometry, which is straight initially, remains mostly so throughout the SCG. Theoretical investigations have been done using an elastic-plastic finite element scheme and the COA/COD criterion as the criterion governing the growth. Finite element results, assuming plane stress and plane strain conditions separately, on the load-sliding displacement diagrams, J-resistance curve, plastic zones and variation of equivalent stress and strain along the crack-line ahead of the crack tip are also presented. The resistance curve is a straight-line and the magnitudes of equivalent stress and strain increases as the crack extension proceeds. In general, the predictions based on the assumption of plane state of stress are closer to the experimental results.