3431 NASSAU ST 2018-01-02 MF Import

04/14/04 07:18 FAX 4253476588 CBBA EVERETT U 017/032 (leologiclnve.slh¢atinn and <ieuuxhr'iC01linemeerine Ketxrrr 00 02-20 NE Comer 35"' St. and Nassau St Everett, Washington and final grading plans result in footing elements being placed on top of' structural till, GES, Inc. should be contacted to develop specific foundation design requirements for the building prior to the start of construction. Foundations for two-(2) to three-(3) story buildings placed upon gray brown to blue gray, sandy silts and silts, CDF, or upon 2" — 4" crushed rock should consist of minimum 24" wide standard spread footings located a minimum 18" below adjacent exterior grades for frost protection. Foundations for one -(I) story sections of the building, placed as outlined above, should consist of a minimum 18" wide standard spread footing located a minimum 18" below adjacent exterior grades fir frost protection. Isolated and point loaded footings should be a minimum 24" square. A four-(4) inch mat of 2"-minus crushed rock should be placed below exterior foundations elements to minimize potential for hydrostatic pressures upon the base ofthe footings where bearing soil consists of sandy silts to silts (Qlh) For foundations placed and sized as outlined above, we recommend utilizing a maximum safe bearing capacity of 2000 pounds per square foot U).0 for design purposes. The allowable bearing pressures may be increased by up to 1/3 to accommodate short term, seismic and transient loads. Foundation settlement will be closely related to the quality of the site earthwork and the degree that the native soil has been disturbed during construction. For the alternative given above, we estimate that total and/or differential settlement potentials Ior foundations placed as recommended above should not exceed '/4" and'/" respectively. It should be noted that actual settlements cou!d increase if care is not exercised during site development and foundation construction. Given the type ohstnrctures proposed on this site, slab on grade floor designs may be utilized for portions of the lower level We would suggest that the slabs be placed on a minimum four-(4) inches of clean sand and that the slabs be as thick as is econe nically possible for the client. If a vapor barrier is placed below the slab, we recommend that a minimum two-(2) inches of sand be placed between the slab and the barrier to allow for proper coring of the slab at the time of construction. All backtill placed behind walls or around foundation elements should be placed per the recommendations contained in section 4.3, Structural Fill ur within this section of the report. For basement foundations or walls placed below adjacent exterior grades on this site, the following recommended earth pressures are 13 GES, Inc.