This paper presents a contribution for the safety assessment of historical masonry buildings under seismic loading. Three different simplified safety indexes (in-plan area ratio, area to weight ratio and base shear ratio) are analyzed, taking into account a large sample of fifty-eight Portuguese churches. The sample of building has been organized according to the seismic zonation, from high to ...

This paper discusses the experimental set-up and procedures for the seismic testing and evaluation of a sprinkler system in hospital model. Concrete compression tests are ran to ensure compliance with ACI 355.2 anchor testing qualifications. Maximum shear strength of the anchor is found to include within the piping system model. Frame and piping system within the model is tested under input mot...

The updated version for the Manual of Civil Structures (MOC), a model seismic code in Mexico, was published in 2008. MOC also is incorporating guidelines for the seismic design of base-isolated structures this year 2012, being the first Mexican code to include such recommendations. This paper summarizes the most relevant aspects of these guidelines, their relations to other guidelines worldwide...

Several seismic phases that scattered within a few hundred kilometers of the base of the mantle are observed in a very dense seismic section. The Los Angeles Region Seismic Experiment passive phase array was composed of 88 seismometers placed along a 175 km profile. Records from two deep earthquakes in Tonga and one earthquake near Honshu, Japan show a secondary arrival between clear P and PcP ...

Seismic interferometry refers to the process of retrieving new seismic responses by crosscorrelating seismic observations at different receiver locations. Seismic migration is the process of forming an image of the subsurface by wavefield extrapolation. Comparing the expressions for backward propagation known from migration literature with the Green’s function representations for seismic interf...

Acoustic emissions from a 2120 cubic in air-gun array were recorded through a towed hydrophone assembly during an oil industry 2-D seismic survey off the West Wales Coast of the British Isles. Recorded seismic pulses were sampled, calibrated, and analyzed post-survey to investigate power levels of the pulses in the band 200 Hz-22 kHz at 750-m, 1-km, 2.2-km, and 8-km range from source. At 750-m ...

Seismic and acoustic noise from moving tracked vehicles was used to determine the seismic to acoustic signal coupling ratio (SAR) in the ground. The seismic signal received on a geophone contains some energy that has propagated as seismic waves and some energy that couples from acoustic waves to seismic waves in the vicinity of the geophone. We use the frequency domain coherence between the mic...

[1] We constrain the anisotropy associated with a very low velocity province (VLVP) at the base of the Earth’s mantle using the SKS and SKKS waves sampling the region. Our selected high-quality data sets consist of 415 SKS and 111 SKKS waveforms for 127 deep earthquakes recorded at distances between 90 and 150 by the seismic stations in three temporary broadband PASSCAL seismic arrays: the Kaap...

Recently developed numerical simulation technique can simulate the coupled seismic and electromagnetic signals for a double couple point source or a finite fault planar source. Besides the source effect, the simulation results showed that both medium structure and medium property could affect the coupled seismic and electromagnetic signals. The waveform of coupled signals for a layered structur...