3322 BROADWAY 2023 COMPASS HEALTH Plans 2025-09-26

References Broadway Block Phase II & III, ASI-02 Set, by Ankrom Moisan dated 5/1/2023 Shoring Plan and Elevations Reference Drawings by BNBuilders dated 8/18/2023 Geotechnical Engineering Study, Proposed Building 3322 Broadway Ave, by Geotech Consultants Inc. dated 6/26/2019 Project Description The project consists of a new medical building in Everett, Washington, that is being built on the site of an existing building that is to be demolished, with part of the existing structure to be abandoned in place. The site is bordered to the west by an alley, 33 d Street to the north, Broadway to the east, and future development of the remaining block to the south. Existing grade at the site ranges from approximately elevation 101 to 86 feet, sloping from west to east. Bottom of excavation varies to accommodate the proposed structure. Subsurface Conditions The geotechnical report indicates that the site soils consist of 9 to 10 feet of loose fill along the western side of the site overlaying dense to very dense glacial till. The depth of the fill layer decreases from west to east. Groundwater was not observed, but may be found in pockets within the glacial till. Along the western side of the site, including the western portion of the shoring wall location,the basement portion of the existing building is to be abandoned in place and will be filled with CDF backfill. Shoring System Cantilevered soldier piles will be utilized to temporarily shore the excavation. After pile installation, sequential lagging and excavation will be completed until the bottom of excavation is reached. Design Parameters Design earth pressures corresponding to the self-weight of soil are recommended in the geotechnical report. The design earth pressure distribution for temporary cantilevered soldier pile shoring is specified as triangular with equivalent fluid density of 30-pcf. An allowable passive resistance of 400-pcf was used, which provides a safety factor of 1.5 on the geotechnical report recommendation for ultimate passive resistance on soldier piles of 600-pcf. To account for traffic and construction surcharge, a 100- psf uniform horizontal pressure was applied, which is equivalent to approximately 350-psf vertical surcharge behind the wall. We have been notified that there will be no need to support concentrated material or equipment loading (such as a crane) that would exceed the included value.