Stress intensity factors of pressurized surface cracks at the internal surface and un-pressurized surface cracks at the external surface of an internally pressurized cylinder are estimated from stress intensity factors of a semi-elliptical crack in a finite-thickness flat plate. Curvature effects of the cylinder are determined by comparing two-dimensional finite element solutions of fixed-grip, single edge-notched plates and single edge-notched cylinders. Stress intensity factors for semi-elliptical cracks with crack aspect ratios of b/a = 0.2 and 0.98 at crack depths up to 80 percent of the cylindrical wall thickness are shown for internally pressurized cylinders with outer to inner diameter ratios, Ro/Ri, ranging from 10:9 to 5:4 for outer surface cracks and to 3:2 for inner surface cracks.

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The dynamic response of the cam-driven mechanism is investigated for a variety of cam motion profiles. Based on a linear, lumped system model of single degree of freedom, the results of the response characteristics of the follower are presented in the form of nondimensional primary and residual shock response spectra. These spectra are also recasted in four-coordinate log-log grid forms. The extension of this approach to treat the system model of two degrees of freedom is delineated. Furthermore, the analysis of a two-freedom model of the cam-driven system was also undertaken to clarify the effects of many system parameters and for obtaining an optimal design. Fundamental design charts are presented.

The dynamic responses of the cam-driven mechanism are investigated, based on a non-linear lumped system model. The nonlinearity is an energy-dissipating element which consists of viscous, quadratic, Coulomb and static frictions combined. The nonlinear equation of motion of a single degree of freedom is first analyzed using a numerical method and the results of time responses are presented and characterized in the phase-plane. The primary and residual shock response spectra in nondimensional form for a number of typical cam input excitations are presented and compared with those of the associated linear cases.

Stress intensity factors of corner cracks at the bore of a rotating disk are estimated from the stress intensity factor of a quarter-elliptical crack in a quarter infinite solid and pressurized by the hoop stress. Curvature effect of the bore is incorporated through a curvature correction factor derived from the stress intensity factors of a single edge-cracked bore in a large plate and a single edge-cracked semi-infinite plate. Stress intensity factors for quarter-elliptical cracks with crack aspect ratios of b/a = 0.2, 0.4, and 0.98 at crack depths of b/Ri = 0.1, 0.3 and 1.0 in a rotating disk with R0/Ri = 8 are determined. Application of the developed procedure to corner crack problems at a through-bolt hole is indicated.