This paper reviews ground fault protection and detection methods for distribution systems. First, we review and compare medium-voltage distribution-system grounding methods. Next, we describe directional elements suitable to provide ground fault protection in solidlyand lowimpedance grounded distribution systems. We then analyze the behavior of ungrounded systems under ground fault conditions a...

Thrust fault earthquakes are studied in a laboratory earthquake setup previously used to investigate analog strike-slip seismic events. Dynamic mode II ruptures are generated along preexisting faults in an analog material, Homalite H-100, and their interaction with the free surface is studied for both sub-Rayleigh and supershear rupture speeds. High-speed digital photography and laser velocimet...

The damaged rock around mature faults forms a zone of low seismic wave 24 velocities, which can perturb important earthquake rupture properties. In particular, waves 25 reflected within the fault zone structure can induce short-duration slip pulses, an apparently 26 predominant earthquake rupture mode. Another known mechanism to generate slip pulses is 27 strong velocity-weakening friction. Her...

The finite element model of a new staggered story isolated structure is established. Using the time-history analysis method, dynamic response state at each time step calculated by integrating acceleration data step-by-step. Three different types seismic waves (ordinary wave, near-fault impulse far-field quasi harmonic and long-period wave) are input respectively for history analysis. result ind...

although there is enough knowledge indicating on the influence of frequency content of input motion on the deformation demand of structures, state-of-the-practice seismic studies use the intensity measures such as peak ground acceleration (pga) which are not frequency dependent. the v max/a max ratio of strong ground motions can be used in seismic hazard studies as the representative of frequen...

There is much practical need in obtaining independent information about earthquake-source dynamic properties directly from observable data. One such dynamic parameter, the peak slip velocity during earthquake rupture, can be calculated from the corner frequencies of the source spectra, on the assumption of the validity of the ω-source model. To obtain the source terms, observed Fourier spectra ...