The data from five strong-motion accelerograph stations centered above and surrounding the fault are used to develop an approximate three-dimensiunal dislocation model for the San Fernando earthquake. In the resulting model, the dislocation originates near the instrumentally determined epicenter at a depth of 9.2 km and then propagates southward and upward with a velocity of 2 kin/see. Calculat...

The Natural Resources Building (NRB) in Olympia, Washington, was shaken by three earthquakes (Mw = 5.8, 6.8, and 5.0) between 1999 and 2001. Building motions were recorded on digital accelerographs, providing important digital recordings of repeated strong shaking in a building. The NRB has 5-stories above grade with 3 sub-grade levels and a ductile steel-frame elongated in the E-W direction. T...

On 8 January 2022, an M S 6.9 earthquake occurred in the Menyuan county, Qinghai province at northeastern margin of Tibetan Plateau. A dense observatory network consisting accelerographs and intensity meters has obtained many acceleration recordings this region, which previously had only a few strong motion recordings. Using data recorded by 141 micro-electro mechanical system (MEMS)-based with...

Time-history analysis is defined as a kind of dynamic analysis increasingly used in design of structures and evaluation of existing ones. One of the important issues in the Time-history analysis is selecting earthquake records. In this case, seismic design provisions states that time histories shall have similar source mechanisms, geological and seismological features with region under study. A...

Most instruments used in seismological practice to record ground motion are pendulum seismographs, velocigraphs, or accelerographs. In most cases it is assumed that seismic instruments are only sensitive to the translational motion of the instrument’s base. In this study the full equation of pendulum motion, including the inputs of rotations and tilts, is considered. It is shown that tilting th...

On average, soil sites behaved nonlinearly during the M 6.7 1994 Northridge, California, earthquake. This conclusion follows from an analysis that combines elements of two independent lines of investigation. First, we apply the stochastic finite-fault simulation method, calibrated with 28 rock-site recordings of the Northridge mainshock, to the simulation of the input motions to the soil sites ...

This article explores the possibility to measure deformations of building foundations from measurements of ambient noise and strong motion recordings. The case under study is a seven-storey hotel building in Van Nuys, California. It has been instrumented by strong motion accelerographs, and has recorded several earthquakes, including the 1971 San Fernando (ML ˆ 6.6, R ˆ 22 km), 1987 Whittier–Na...

Several groups are implementing low-cost host-operated systems of strong-motion accelerographs to support the somewhat divergent needs of seismologists and earthquake engineers. The Advanced National Seismic System Technical Implementation Committee (ANSS TIC, 2002), managed by theU.S. Geological Survey (USGS) in cooperation with other network operators, is exploring the efficacy of such system...

We applied a time-domain method to continuously monitor groundmotion parameters to facilitate rapid determination of the geographical distribution of ground motion and earthquake parameters. This approach minimizes the impact of the sudden increase in the workload on data acquisition facilities and streamlines the operation of a seismic network, especially during a complex earthquake sequence. ...

We applied a time-domain method to continuously monitor groundmotion parameters to facilitate rapid determination of the geographical distribution of ground motion and earthquake parameters. This approach minimizes the impact of the sudden increase in the workload on data acquisition facilities and streamlines the operation of a seismic network, especially during a complex earthquake sequence. ...