1315 PACIFIC AVE 2018-01-01 MF Import

Lateral Reslstanee Lateral foundation loads may bc resisted by passive rcsistance on the sides of the footings and by (riction on the base of the footings. For footinFs supponcd in accordancc with our reconvnrndations, the allowable frictional resistance may be computed using a wc�cient of friction oC 0.4 applied to vertical dcad-load forccs. The allowable passivc resistance may be computed using an equivalent tluid drnsity of 400 pounds per cubic fool (pcQ if thc footing is poured directly against undisturbed native soils. If the footing is swrounded by structural fill, the allowable passive resistance may bc compWed using 300 pcf. The structural fill should catend o�t from the face of the foundation clemcnt for a distance at least equal ro threc times the height of thc cicment and be compacted ro at Icast 95 percent of the ma�cimum dry densiry (MDD) in accordance with ASTM D1557. Thc above cocfficicnt of friction and passive cquivalent fluid density values can be combined and include a factor of safcty oC about I.S. The allowable passive and friction values can bc incrcased by one-third(or wind and scismic laads. ConstrucNon Conslderations Thc footing subgradc soils for thc Potala Villagc building may bc susccptiblc to disturbance by construction activities or when wct. Thercforc,to protect the footing subgrade, we mcommend placing a lcan concrctc "mud maC' or a thin laycr of Ican concrctc on thc bottom oC thc footing excavations to protect thc footing subgradc soils from water and/or wet weather during rcinforccment bar placement and preparation for concretc placcment. We recommend Ihat the condition of all footing excavations bc obscrved by a represcntati��c Gom our firtn prior to placemcnt of wncretc to confirtn Ihat the bearing soils are undiswrbed and arc consistent with our rccommendations contained in this repart. Existing fill not removcd from bclow planncd foundations will likcly result in excessivc setticment o(the foundations. PARKING LEVEL SLAB-ON-GRADE Subprade Preparatlon The exposed subgrade should bc e�•aluated aflcr excavation and site grading is camplete. Proof-rolling witl�hcavy,rubbervtired conswction equipment should be used for this purpose during dry weather and if access for this cquipmcnt is practical. I'robing should be uscd to cvaluate the subgrade during periods of wet wcathcr or if acccss is not fcasible for construction equipmcnt. The exposed soil should be firtn and unyiclding, and without significant groundwatcr. Disturbed arcas should bc re-compactcd if possible or removed and replaced with compacted swctural fill. R�c rccommend that the upper 12 inches of the cxposed subgradc soils he rcwmpacted Io at Icast 95 percent of the MDD, after the site is proo6rolled. Whcre significanl arcas of sofl soils cxist, thc slab subp.ade may nccd to be ovcrexcavated up to 2 feet and bc rcplaccd�s•ith swclural fill. Deslpn Parameters Thc parking lercl slab may bc supportcd on-gradc providcd thc subgradc soils arc prcparcd as rccommcnded under the "Subgradc Prcparation" above. Wc rccommcnd that the slab be founded on cithcr undisturbed glacially consolidatcd soils or on structural fill placed over a preparcd subgrade. The slabs-on-grade should bc supportcd on a minimum 6-inch-thick laycr of 1'h-inch minus clean crushed gravcl with»cgligiblc sand or sill,to provide uniforni support and fonn a capillary break beneath the slab. Por slabs dcsigncd as a bcam on an clastic founJation, a modulus of subgradc rcaction of 150 pci may be used for ad%ivately preparcd subgrade soils. If moisturc•sensitivc (loor coverings will bc used, we also r;i�.�� nnz-rro�-nn Page 11 GtoEMenMt�s� hmr 6.:lIO.Y '7