Laserfiche WebLink
i <br /> IGEOTECHNICAL ENGINEERING REPORT 9-91M•12723-0 <br /> � PROVIDENCE FAMILY SERVICES CENTER <br /> � PACIFIC CAMPUS <br /> PROVIDEhCE GENERAL MEDICAL CENTER <br /> PACIFIC AVENUE AND KROMER AVENUE <br /> IEVERETT,WASHINGTON <br /> � 1.0 SUMMAR'f <br /> � The following summary af project geotechnical considerations is presented for introductory <br /> purposes and, as such, should be used only in conjunction with the full text of this report. <br /> I • Proiect Descriotion: Development plans call for demolition of the existing medical <br /> office building and pharmacy and construction of a new four-or five-story,at-grade <br /> I Family Services Center. One or two additional upper stories might be constructed <br /> at a f�ture time. <br /> I • Exoloratorv Methods: We explored subsurface conditions by means of ten borings <br /> advanced at strategic localions across the project site,to depths ranging from about <br /> 14 to 44 feet below existing grades. We also reviewed the logs of our subsurface <br /> Iexplorations conducted in 1991. <br /> • Soil Conditions: Soils underlying the site generally consist of loose to <br /> I medium-dense, sands with varying amounts of fines and gravel ar�d dense to very <br /> dense, silty sands with gravel (glacial till). The depth of this ciacial till horizon <br /> ranges from about 2 feet at the eastem sida of the site to about 40 feet at the <br /> Inorthwestem comer. <br /> • Groundwater Conditions: No groundwater was encountered at the time of drilling. <br /> I However, perched water could form atop the glacial till horizon after extended <br /> periods of wet weather. <br /> • Slooe Stabiliri Conditions: Our analysis of the existing ravine slope revealed <br /> aCey�;ate safery factors against failure under static conditions. Under strong <br /> ( earthquake conAitions (0.28g acceieration), we found that safety factors dropped <br /> to a marginal value, indicating a risk of failure, but such a failure would likely <br /> originate less than 15 feet from the slope brink. <br /> ( • Foundations: Due to the variable depth of the glacial till horizon, we recommend <br /> using a composite foundation consisting of spread footings for the southeastern <br /> I portion of the building and augercast piles or drilled piers for the northwestem <br /> portion. Allowable bearing capacities of 8000 psf for footings and 54 to 150 tons for <br /> 14-to 36-inch-diameter pileslpiers would be appropriate. If a basement is inGuded <br /> Iunder the building, spread footings could be used more extensively. <br /> I <br /> I 5�.�VOFDPROC�99 Pmlcas�Seai0eu2000s�1I�:7 R:o�nsw��PrarCence Mmp�RptwpE /� <br /> V <br /> � <br />