4815 EVERGREEN WAY 2016-01-01 MF Import

JP Morgan Chase Apn129, 2010 Geotechnical lnvestigafion Proposed Chase Bank Everetf, WA PSI Report No. 0704186 occurred. We offer the following comments and recommendations for purposes of footing design and construction. Footing subgrade soil should consist of inedium dense to very dense silty sand or silty/sundy gravel. Footings should not be cast on loose, soft, or frozen soil; slough; construction debris irom demolition; organic materials, existing uncontrolled fill; or surfaces covered by standing water. Care should be exercised so that no large pieces of construction debris remain in the subgrade level after demolition. Large chunks of concrete and asphalt should be removed and disposed of off-site. Should unsuitable soil be encountered during footing excavations, those soils should be removed and replaced with granular structural fill. Continuous wall and spread footings should be proportioned for an allowable bearing pressure of 3,000 psf. The maximum extreme frosl depth in the Everett, Washington area is on the order of 8 to 10 inches bgs. Continuous wall foundations should be at least 18 inches wide. The bottom of exterior footings should be at least 24 inches below the lowest adjacent final grade. The bottom of interior footings should be placed at least 12 inches below the bottom of the floor slab. The recommended �Ilowable bearing pressure applies to the total of dead plus long-term live loads. The allowable bearing pressure may be increased to 4,000 psf for short-term loads, such as those resuiting from wind or seismic forces. In view of the pre-consolidated nature of the on-site soils within the existing Hollywood Video structure footprint, estimates of static set:tlement for the new bank structure are less than one inch total. Differential setilement should �eneratly be less than one half of totai settlement. 4.7 LATERAL RESISTANCE FOR FOOTINGS Lateral loads of the proposed buildings founded on a suitable granular (sand or gravel) material can be resisted partially or completely by frictional forces developed between the base of the spread footings and the underlying granular material. The total shearing resistance between the foundation footprint and the soil should be tak�n as the normal force, i.e., the sum of all vertical forces (dead load plus live load) times the coefiicient of friction between the soil and the base of the footing. We recommend using lhe Coefficients of Friction provided in Tabfe 2. If addilional lateral resistance is r�q�ired, passive earth pressures against embedded footings or walls can be computed using a prrssure based on an equivalent fluid with a unit weight of 250 pcf. This value assumes the bar,kfill around foolings will be placed as granular structural fill or the footings were cast in neat-formed excavations and the sur�sce of the area in front of the footings will be horizontal in eil;�er case. r�rtr N�� 6