Progressive destruction of buildings and other works of man at the W. A. Taylor Winery near Hollister, California, indicates that one side of a segment of the San Andreas fault is creeping relative to the other. Three different types of measurements all yield an annual rate of creep of approximately one-half inch per year. Steinbrugge and Zacher: Measurements of the separations of pairs of reference marks adjacent to the line of creep have been repeated periodically since 1956, and damage to structures provides a good measure of the total creep since 1948. Reports of damage to older buildings on the same site suggest that the creep may have been going on at about the present rate for fifty or more years. Tocher: Creep recorders designed to measure continuously the differential lateral movement of adjacent sections of the concrete floor have been installed in the main winery building. The creep rate so determined has been about one-half inch per year (with right-lateral sense) for the past two years. Creep accumulates largely in spasms of rather short duration (on the order of a week) separated by intervals of weeks or months during which little or no creep takes place. Ninety-two per cent of the movement in a recent 371-day period accumulated in four spasms of total duration 34 days. Three of these spasms began at times when no local earthquakes were recorded on near-by seismographs; the fourth began with a sudden right-lateral fault movement of 3 mm. at the time of a sharp local earthquake (Richter magnitude 5.0) on January 20, 1960 (GCT). Whitten and Claire: Resurveys over monumented points established near the winery also yield a rate of slippage or creep along the fault line of one-half inch per year. A new method for analyzing the data obtained by retriangulating over monumented points at wide intervals (10 to 20 years) is presented and applied to two triangulation networks which cross the San Andreas fault in central California. Results from a net near Hollister show an average creep rate of about one-half inch per year; results from a net near Cholame (about 75 miles southeast of Hollister) show an average creep rate of about one-tenth inch per year. The results also give an angular value which represents the deformation in the crust adjacent to the fault line.

Geographic area covered by the study 10 Building classification 12 Historical background of building classifications developed for insurance purposes 12 Building classification used in this study 13 Building inventory 28 Examination of existing inventory sources 28 Development of a building inventory for this study 30 Notes on inventory development applicable to specific Ground shaking-loss relationships 43 XII SUMMARY This study is the eleventh in a series of investigations, beginning in 1967, dealing with the estimation of earthquake damage to various types of buildings. A methodology is developed in this report for determining inventory and estimating losses resulting from various postulated earthquakes occurring individually and for various ensembles of earthquakes. Five broad classes of buildings are considered. The building classes studied cover most of the building types in the San Francisco Bay area with the exception of one to four family dwellings, lifeline facilities, and special types of structures such as oil refineries and storage facilities, military installations, and bridges.One to four family dwellings were considered in an earlier report (Rinehart and others, 1976). This methodology, based on the seismic record, ground shaking, construction practice, and building inventory in the San Francisco Bay area can be adapted with appropriate adjustments for use in obtaining rough estimates of probable earthquake losses in other areas of the country.Adaptation of the methodology developed for the San Francisco Bay area to other areas of the country will require careful attention to differences in design and construction practice, loss-ground shaking relationships, and inventory methods. The most difficult problem in transferring this methodology to other areas of the country will be in obtaining suitable building inventories. The building inventory method developed here depends on land-use classification in the San Francisco

The series of major earthquakes which occurred in south-central Chile during May of 1960 were of large Richter magnitude and were accompanied by major geologic changes. Epicenters were distributed throughout populated regions; the earthquakes violently shook many substantial buildings which had been specifically designed to resist earthquake forces. In general, damage to earthquake resistive structures of reinforced concrete, structural steel, and wood frame was slight and the overall performance was quite satisfactory. When major damage did occur to structures with earthquake bracing, construction practices were almost always recognizably poor. The minor damage to earthquake resistive structures was instructive and a number of case histories are discussed. Of particular interest are the instances of shear wall rotation on compressible soils, construction and design errors, relative rigidity problems, and the performance of inverted pendulum structures.

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