Planning and Design of Strong-Motion Instrument Networks,United States -Japan Panel on Wind and Seismic Effects,May 18-21, 1976,

摘要

The development of criteria for the planning and design of networks and arrays of instrumentation to measure ground motions involves the following steps: (1) the ground motions must be estimated; (2) the costs of operations must be evaluated;and (3) the benefit derived from the data must be assessed. A similar process is also required as the first step in the process of planning instrumentation arrays for structure. The estimation of ground motions involves a determination of the tectonic setting,the seismicity of the region,and the recurrence of strong ground motions. In this basic approach to estimating ground motions,the source characteristics are modeled in terms of the recurrence of earthquakes of different magnitudes;the transmission of the motion is modeled as an attenuation of peak acceleration;and the motion at the site is obtained as a recurrence relation for particular site conditions. Most of the existing strong-motion records have been obtained in California and the technique for estimating ground motion spectra are largely based on these records. Preliminary evaluations for other regions of the United States suggest that the Mississippi embayment and Yellowstone Park regions may provide as much data,and as inexpensively,as some of the less active areas of California. High maintenance costs in Alaska offset the advantage of the generally high level of activity in that region. Instrumentation designed to study soil failures through liquefaction or landsliding can be incorporated into the regional arrays if areas subject to soil failure are identified. This instrumentation should be installed only in highly active areas.