1208 50TH ST SW 2017-01-27 - Laserfiche WebLink

Alht�ssaini Property --� Updated Recomme�adatioxas NGA I�ile No. 467b 12 t.Tltra Block Reinfc�rced Soil 0�,�'all February 14, 2013 F..verett, tTJashin�ton Pa�e 2 underlie tl�� sit� should provide adec�uat� suppo�-t for t�he reinfore�d fil] and lii�ra B1ock facin,� provided that tIle sut��racie excavatin��s are adva��ced thrau�ll any existine Cil and loose material, and are extended into medium dense or �etter iiative sqils or struct�iraI �li exte�ndi�ng to these soils as directcd by NGA. "i'iie total liei�ht of the plani�ed wall is expected to be up Co i2.� feei, including a minilalum rccommend�d eilibedment of 1� inches into coinpetent native materi�l. �Vc hav� provided a desig�� for ��ip to a 12.5-foot- hi�;h reinfarced earth reTaining wall with liltra Block facing. 7't�e propased location oFtl�e retainang wall is sho��n on the Sch��liatic Ultra 731�ck Wall Site Plan in �'i�t��-e 1. Ti�e wall details, al��ng with construct�ion notes, are shown on t2ze Ultr� �31ock Reinfarced Eartli tual] T�etail attached as Fi��ure 2. �i�e have assumed tltat the reinforced fi'll zoue will crnisist of granuiar tnateri�i c�mpacted fo structural fill. s�ecifications. The backfill will be leveI a%ove the wall, and a ciraina�e systenl, as indicated on Figure 2, wi1l be ins�alled behind the block facing. The Ultra �31ock wall should 6e plaeed c�n a��inirnum 6-inci� ihick paci of c�-ushed rock extericiing � minimum of t�ne foat co the froi3t and back �f ttie blc,cks. Tlie are� c�f th� p}anned Ultra Block wall and �-einforced fill s�ic�uld be excavated to tlie plan�ietl subgr��: el�vatic�n tc� expos� coznpetent native soils. 11xiy Ioose or ar�anic z��aterials that are expc�sed si�oulcl t�e r�ernovec� frc�m tize suvgrade. T17e eaposed soil sho�ild bE cam�act�cl io a nc7n-y-ieldiilg condition befc�re placing ttze blc�cks. `T'}�e bott{�zn af ihe Ultra Block wall should also be embedded a minimum of 18-inches into the underlying soils. A draina�e blanket of 12 inches of free-draining 1%-ineh eleari ci-uslzed rock sllould be placed between the blocks and the reinforced earth zone. Slrata�rid SG500 and SG 200 geogrid {or equivalcn[) is t•ecotnmend�cl in the tivall design. 'I'}ae geogrid sljoulc� be c:i�t to tl�e rec�nunctided len�tl�s anc� extenaed l�ack inio the reinforceci Cill zone. 'I'he �rid sl�aulcl be �uileci ti�ht befure �th�; tzll is placed over tP�,e geo�,�-id. C�re shoutd �be taken to not danzage the geogrid by o�aeratillg consin�ctian �quipmer�t on fl1e ehpased �rid, or by allou�ing large rocks tc� be placed dir�ctly on the �rid. Th�: geogrid shauld be interlockec� bet��een each ra�,�- of blocks as shUtivn on the attached detail. I� a fence or rail is planned alon� the top af the w�ll, it will be important ta establish the layout c�f ai�v su�port posts pxior to cc�nstracting tlte wali. F��txlation far��is �r Sona mbes s�raul� be installed at tl�e post loca�io��s durzug plaoement af t-l�e rcinforced �ill to allow for laier placeinent «f �t�e �Cence pas�ts wiYh��ut having to excavaie into the reiYiforceci fill. �ny excavation in the reinforced fi11 zone will damagc fhe geogrid and cornpromise the, reinfc�rced sc�il �vall and should not be ailowed. idELSOM GEOTECH/V1CAL ASSQCIATES, JNC.