3121 8TH ST AB 2016-01-01 MF Import

Jwic l. 2008 Duplex Building L&A Job No. 8A055 Page 11 A ono-third incrcosc in the .ihovc recotnmendctl allowablc soil bearine pressurc may be used when considering short-term, transitoty, wind or seismic loads. For 1'ooting foundations desig;ial 1nd constructed per recommendations above, we estimate that the marimum total post- construction scttlement of thc buildings should be 1/2 inch or less and the diffcrentiul sctticment across building width should be 3/8 inch or Icss. Lateral loads on buildings can be resisted by the l�iction force between the fow�dations �md the subgradc soils or tlre passive earth pressure acting on the below-grade portion of the foundations. Por thc latter, the foundations must be poured "neat" a�ainst undisturbed soils or backiilled with a clean, tree-draining, compacted structural fill. We recommend that an equivalent fluid density (GI'D) of 325 pcf (pounds per cubic foot) for lhe passive earth pressure be used for lateral resistance. "I'he above passive pressure �ssumes that the backfill is level or inclines upward behind the foundations for a horizont�l distance at least twice the depth of the foundations below 6nal grade. A coci7icient of f'riction of 0.60 between the foundations and the subgrade soils may be used. 1'he above recommeiided soil par�tmeters are unfactored values, and a proper factor of safety should hc uscd in calculating thc resisting forccs :�gainst lateral loads on dic duplex buildin¢. BUILllING Sr7'�3ACK Thc pury�ose of building sctback irom thc top or loe or an cverly stcep portion of a slope is to establish �i safc bufter such that if a slopc failure should occur on thc slope, the stability of the structure can be maintaincd and damages to the si�ucture minimized. Pactors affecting required setback of the new residence 1rom ihe crest of adjacent steep slope include: geological constraints (such as soil and hydrological conditions) of the site, hazard from development to subject property and surrounding propertics/right-ol=ways, impact of wnstruction method and iechninue LIU & ASSOCIATES, INC.