1920 GRAND AVE 2016-01-01 MF Import

Seismlc Conalderallons Construction should be in accordance with current Unifocm Building Code (UBC)related to potential seismic loading for the region. 'Ilie propecty is located within the Puget Sound region which has been clazsified u a Zone 3 seismic area. According to Table 16-J of the 1997 UBC(Apptndir),the soils should be clazsified as Sc. Potentlal Settlement If the foundations are placed upon the dense native soils pad as recommended, the settlement that can be expected is in the range of one-half to one inch. Any settlement which occurs will most likely take place during conswction. Overall,differentiai setdements that can be anticipated are about one-half inch. Slab-on-Grade The interior slab-on-gwde should be placed upon a capillary break which may consist of a compacted swctural fill. This will serve as both a compacted mat for floor support and a capillary break as long as the fill is ftee dtaining. We further recommend that an impervious moisture bamer be placed beneath the slab. If the slab is placed upon a properly compacted base,a modulus of subgrade reaction of 200 pci may be utilized. Retalning Structures For the design of basement ataining walls, a tluid equivalent pressure of 40 pcf may be assumed if the wall is allowed to yield an amount equal to 0.001 times its height. Walls that are not allowed to yield should be designed to withstand fluid equivalent pressures of 55 pcf. Walls backfilled at the base i with native soils may resist 250 pcf for an equivalent passive resistance and a 035 ccefficient of friction used for sliding. The pressures given allow for shorc-tecm loading during a one in 100•year seismic event and assume a I drained condition with no static water build-up and level backfill. In the event of sloping backfill,an additional one pcf should be added for each degree of I slope inclination behind the wall to a maximum of 33 degrees. Slopes behind � the retaining walls should not exceed 33 degrees or 1.SH:1 V. � Backfil! adjacent to the retaining walls should consist of a suitable free- ; draining granular fill. Granular soil fill should be a moderately to poorly- graded sandy gravel with less than five percent fines capable of passing a I standard U.S. No. 200 sieve. Granular fill should be placed next to the foundaiion wall, fortning a 12-inch vertical layer that will provide drainaFe. Fill matenal placed outside of the 12-inch drainage layer should be compacted in horizontal layers to a non-yielding condition. Fill material should be keyed into the native soils adjacent to the excavared foundation. Gravel drain rock should be placed at the base of the drain and should be protected from the Port Gartlner Condominiums•GeotecDnical Report �9e 7