In this paper, we retrieved relative source time functions (RSTF) and estimated the source parameters for microearthquakes (M= -1.9 to -2.6) induced by hydraulic injection at Fenton Hill, New Mexico, using an empirical Green's function (EGF) method. Seismic waveform of a small event in seismic doublets or multiplets (Gelle and Meuller, 1980), defined as co-located events with similar focal mech...

A new model accounts for crystal growth patterns and internal textures in quartz cement in sandstone fractures, including massive sealing deposits, thin rinds or veneers that line open fracture surfaces, and bridge structures that span otherwise open fractures. High-resolution cathodoluminescence imaging of bridge structures and massive sealing deposits indicates that they form in association w...

Objective: To determine the efficacy in treatment of vertically unstable sacral fractures with pelvic external fixation and skeletal traction. Patients and Methods: The pelvic external fixation and skeletal traction were applied on 12 cases of vertically unstable sacral fracture (eight males and four females, at age of 19 52 years, mean 35.2 years) including two cases of Denis Zone I, nine of Z...

A mode-dependent embedded-process-zone (EPZ) model has been developed and used to simulate the mixed-mode fracture of plastically deforming adhesive joints. Mode-I and mode-II fracture parameters obtained from previous work have been combined with a mixed-mode failure criterion to provide quantitative predictions of the deformation and fracture of mixed-mode geometries. These numerical calculat...

Friction stir processing (FSP) 2519-T87 aluminum plate results in enhanced ductility, 25% strain at fracture. However, the yield strength in the FSP zone drops to 175 MPa from �400 MPa. Actively cooling the plate during FSP increases the yield strength to 185 MPa and decreases ductility to 20% strain at fracture. Thick bending of a plate of the alloy was demonstrated after the surface was subje...

Moisture flow in porous media is the driving force behind early age drying shrinkage. Fracture in the interfacial transition zone (ITZ), between cement paste and aggregateinclusion, is related to restraint caused by, among others, aggregates that obstruct free deformation of the paste. Environmental Scanning Electron Microscope (ESEM) test results are used as a base for the developed method for...

We study the sample-size dependence of the strength of disordered materials with a flaw, by numerical simulations of lattice models for fracture. We find a crossover between a regime controlled by the disorder and another controlled by stress concentrations, ruled by continuum fracture mechanics. The results are formulated in terms of a scaling law involving a statistical fracture process zone....

[1] We examine how frictional heating drives the evolution of temperature, strength, and fracture energy during earthquake slip. For small slip distances, heat and pore fluid are unable to escape the shearing fault core, and the behavior is well approximated by simple analytical models that neglect any transport. Following large slip distances, the finite width of the shear zone is small compar...