9001 AIRPORT RD SNO ISLE SKILL CTR EXPANSION 2009 Geotech Report 2018-01-02 MF Import

i ( Subsurface Expbration, Geologic Hazard, and S5w-/sle Skilfs Center Additlon PrtUminary Gearechnical Engineering Repon Eve�ett WashinBron Preliminary Desigrt Recommendations Iacceptable performance of a fill. As such, we aze available to aid you in developing a suitable monitoring and testiug frequency. I � 11.0 FOUNDATIONS I' Spread footings may be used for building support when founded on the medium dense to very � � dense lodgement till, or on new structural fill placed as previously discussed. We recommend � ( tLat an allowable bearing pressure of 3,000 pounds per square foot (ps� (including both dead j and live loads) be utilized for the new building and other neaz-surface foundation design � I purposes. An increase of one-third may be used for short-term wind or seismic loading. No � new structures should be founded on existing fill. � ( Perimeter footings should be buried at least 18 inches into the surrounding soil for frost � protection. All footings must peneuate to the prescribed beazing suatum, and no footing should be founded in or above loose, organic, or existing uncontrolled fill soils. It should be � noted that the azea bounded by lines extending downwazd at 1H:IV from any footing must not � intersect another footing or intersect a filled azea that has not been compacted to at least , 95 percent of ASTM:D 1557. In addition, a 1.SH:1V line extending down from any footing Imust not daylight because sloughing or raveling may eventually undeimine the footing. '17ws, footings should not be placed neaz the edge of steps or cuts in the beazing soils. � Caze should be exercised where new foundations aze to be constructed adjacent to existing building footings. New foundation subgrade elevations should match existing elevations, when � practical. New foundations placed at a higher elevation than existing footings will impose a vertical and horizontal surchazge to the existing foundations and vice versa. We recommend the project structural engineer review the impacu, if any, of new foundations or existing 1 foundations. Anticipated settlement of footings founded on the medium dense to very dense lodgement till, I or approved structural fill placed over these deposiu, should be on the order of �i inch or less, wit6 about half of t6at being differential settlemenu. However, disturbed soil not removed I from footing excavations prior to footing piacement could result in increased settlements. All footing azeas should be inspected by AESI prior to placing concrete to verify that the design bearing capaciry of the soils has been attained and that construction conforms to the I recommendations contained in this report. 1'he City of Everett may requ've such inspections. Perimeter footing drains should be provided, as discussed under Section 14.0, "Drainage Considerations." I I lune 11. 2A08 ASSOCUTFD EAR7N SCIENCES.IN�. I Page 15 I� EG/W-EE080113A5-Pro1�+1100801131F�'1WP