11802 EVERGREEN WAY BASE FILE Geotech Report 2018-01-02 MF Import

08/18/2085 15:27 4257478561 GEOTECH pq,� g� � Lucia Oevelopment, LLC JN U5233 August 1 B,2005 Page 6 not be appropriate. We recommend a safety factor of et least 1.5 for the foundation's resistance to lateral loading, when using the above uftimate passive value." - PERMANENT FOUNDATION AMD RE7A/NING WALLS Fcetaining walls backfilled on only one side should be desig�ied to resist the lateral earth pressures imposed by the soil they retain. The following rewmmended parameters are for walis that restrain level backfill: Active Earth Pressure' 35 pcf 3a'f Unk Wefght 125 p�{ Whsn: (q Pd Ic pounds per cubic foet, and (I) active e�ttfi p�essuros�to eompuped winp the aqWval��d 11Wd pressun.y, ' 'For a mtralrwd vrall Mat pnnot dollect�t least 0.002 Um�s ks � MelghC�unllorm lahral P�uu�*e4tMi W 10 psi tlrms tM hNpht of the wall ahoWd b��ddM to tlie ahove�CUw rquFqNnt fluld � p�255uf0. � The values given above ere to be used to design pertnaneM founda6on and retaining wails only, It is not appropriate to back-calculate soil strength parameters from the earth pressures and sal unft we(ghts presented in the table. We recommend a safety factor of at least 1.5 for overtuming end sliding, when using the above values to deslgn the walls. ResVafned wall soii parameters should he uGlized for a distancs of 1.5 times the wall height from comers or bends (n the walls. This is Intended to reduce the amaunt of cracking that can occur where a wall fs restrained t, a comer. 7he design val�!es given ebove do not include the effects of any hydrostat(c pressures behind the wails ar,d assume that no surcharges, such as those caused by slopes, vehides, or adjace� foundations will be exerted on the walls. If these conditions exist, those pressures should be added to the above lateral so�l pl'essures. Where stoping backfill is desired behind the walls,we will need to be given the wall dimensions and the siope of the bdCkfill in order to provide the appropriat� Besign earth pressures, Yhe surcharge due to traffic (oads behind a wall can typically be accounted for by edding a uniform pressure equal to 2 feet multiplied by the above adive fluid density. Heavy construction equipmerrt should not be operated 'aehind retaining end foundation walls within a distance equal to the height ot a wall, unless the walls are designed fo� the additional later�l pressures resuiting from the equipment llte wall design criteria assume Ulat the badcfill wiil be well-compacted in lifts no thicker than 12 inches. The compadion of backflil near the waps should 6e accomplished with hand-operated equipment to prevent the walls from being overloaded by the higher soll forces that occur during compaction. Retaiqfnct Wal!Backfil!and Waternroofrna Backfill placed behind retaining or foundation walfs should be coalse, free-draining structural fill coritaining no organics. This ba�ll should contain na more ihan 5 percent sllt or ciay particles and have no gravel greater than 4 inches in diameter. The percentage of particles passing the No. 4 sieve should be between 25 and 70 percent. The on•sRe solls GEOTECH CONSULTANTS,INC,