10105 19TH AVE SE Geotech Report 2018-01-02 MF Import (2)

I & ASSOCIATES, INC. ��aZ�l GGOTGCIIMCAL GNCINECRING • E•NVIRONMENTAL L•NGINGERII�G CONSTRUCTION THSTING & INSPLCI'ION ao��,- d�-� Apri16,2007 KA Project No.092-G6160 Mr.Brent 7ohnson D.V.M. Norlliwcst Animal Carc Hospital 10105 1�'h Avcnuc Southcasl Evcrett,WA 98208 ILN�: Gcotcchnical Fnginccring Pavement Design Addendum Lettcr Northwest Animal C�rc Ilospital Yroposcd Addition 10105 19�'Avenue Southe�st Evcrett,Wash'vigton Ref: Geotechnicnl Eneinccrine InvestieaHon Renort 1CA Project No.092-06160,OctoUer 25,2006 llcar Mr.Johnson: At thc request of Jennifer Phnng with Architectural Werks [nc., wc have prepared this ]ctter to provide pnvcment d:;sign recommendations. i�� prcparation of this leticr, wc hnvc rcviewed our gcotcchnical cngineering invcsugation repc:i and d�c soil paramctcrs used f'or thc cnginccring analysis. 13ased on our review of our Gwtechnical �ngineering .nvestigation Report KA Projcet No. 092-06160 d�ted Gctober 25, 2006, Uie near sudace subgrade soils generally consist of silty sand widt variable amounts of gravel. These soils aze ralad as fair to good tor pavement subgradc rosterinl. We cstimalc that the subgrade will have a Califomia Bcaring Ratio (CBR) valuc of 12 and a modulus of subgradc rcaclio�t v�luc of k=210 pci,provided tl�e subgrade is prepared in gencral accordance with our recommcndations. We recommend that, at a minimum, 12 inches of the cxisting subgr�de material be moisture conditioned (as necessary) and re-compacled to prepare for tlic construction of pavcment sections. The subgradc should be compucted to at lcast 95 percent of thc maximum dry density as determined by ASTM Test Mcthod D1557. In place densily tcsts shouid be perCottncd to verify proper moislure contcnt and adcquate compaction. Howevcr, if Ihc subgrade soil consists of firm and unyieiding native glacial soils a proot roll of the pavcmcnt subgnde soil may be performed in lieu of re-compacting the subgrade and compaction tests. '1'hc rccommended flexiblc and rigid pavcmcnt sections 1re based on design CBR and nwdulus of subgradc rcaction(k) valucs tl�at are achieved,only following proper subgradc prcparation. !t s}:ould be noted t}�at suUgrade soils that l�avc relatively I�igh silt contents may bc higlily sensitive to moislurc conditions. "1'hc subgrade strenbnit and performance charncteristics of a silty subgrade material may be dramatically reduced iFUiis mnlerinl becomcs wet. Offices Scrvin�The�Vestern United States I 171 S N.Creck Purkwny S.,C-10(•Dothcll,Washinglun 98011 •(425)485-5519•Fex(425)485•6RJ7 �(/�