W. A. Griffith

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We used optical experiments and high-speed photography to interpret the origins of tensile fractures that form during dynamic shear rupture in laboratory experiments. Sub-Rayleigh (slower than the Rayleigh wave speed, cR) shear ruptures in Homalite-100 produce damage zones consisting of an array of tensile cracks. These cracks nucleate and grow within(More)
[1] We examine the local nature of the dynamic stress field in the vicinity of the tip of a semi-infinite sub-Rayleigh (slower than the Rayleigh wave speed, cR) mode II crack with a velocity-weakening cohesive zone. We constrain the model using results from dynamic photoelastic experiments, in which shear ruptures were nucleated spontaneously in(More)
Various fault damage fabrics, from gouge in the principal slip zone to fragmented and pulverized rocks in the fault damage zone, have been attributed to brittle deformation at high strain rates during earthquake rupture. Past experimental work has shown that there exists a critical threshold in stress-strain rate space through which rock failure transitions(More)
S U M M A R Y The elastic displacement and stress fields due to rectangular faults and opening-mode fractures within an anisotropic homogeneous half-space are derived in this paper. The solution is expressed in terms of the mathematically elegant and computationally powerful Stroh formalism and can be applied to the generally anisotropic half-space or a(More)
Based upon the fundamental solution to a single straight dislocation segment, a complete set of exact closed-form solutions is presented in a unified manner for elastic displacements and strains due to general polygonal dislocations in a transversely isotropic half-space. These solutions are systematically composed of two parts: one representing the(More)
It is well known that the perturbed stress field beneath valleys can result in roof instabilities in shallow underground coal and stone mines. Quantitatively predicting the magnitude of these stress perturbations, particularly beneath complicated three-dimensional (3D) topography, has not become commonplace in mine planning, perhaps due to the complexity(More)
This paper presents the exact closed-form solutions for the stress fields induced by a twodimensional (2D) non-uniform displacement discontinuity (DD) of finite length in an isotropic elastic half plane. The relative displacement across the DD varies quadratically. We employ the complex potential-function method to first determine the Green’s stress fields(More)