3210 36TH PL NE 2018-01-02 MF Import

I, we[season, as compac[ion can be veq� difficult if no[ impossible to achieve. Comnton bortow would still be very susceptible to disWrbance from constniction traffic during the wet ser�son. Structural fill placcd as cnishcd surfacing basr. course bclow pavcments s�tould mcct �\'SDOT Standard Specification 9-039(3) Cor f3asc Coursc. On-site Soi/s The on-site nati��c soils consist of silt, organic silt and silt}' sands Cor N�e most part, with the silt and organic soils' ncar Ihe ground surface in most arcas. 'rhe�c soils contain a high perccntage of fincs and organics, are typically wet, and arc highly sensitive to small changcs in moisture content. They are also higlily suscep[ible to disturbance ltom construction traftic. In their existing condition and once disturbed. thcy will be all but impossible to compact as structural till. The un-site native soils should not Ue plannc�l for ure as structural fill in structural areas. Based on the current desibm coneept, widi tlil Ueing plac�d to raise site grades from� ta l0 Feet, minimal fill will be generated for reuse. FiU P/acement and Compaction Criteria �trucwral fill should be mechanically compactcd to a firm, nan-yielding condition. 'Che strucwral till should bc piaced in liRs. Thc lift thickncss should bc sufficicndy thin so that following compaction, thc entire liti mcets the compaction criteria rccommended below. Lach loose litt thiclmess should not exceed 1 fooi, except for the initial lift over thz geotextilc. Gach liR should be conditioned to the proper moisturc content and compacted to the speciticd dcnsit}�before placing subseyuent lifts. Thinner loos'e lifts may oc nceded to achieve compaction depending on the actual compaction eyuipment used. Structural fill should Ue compacted to the Collowing critcria: • Structural fill placcd to raise site grades in areas where no proposed structures are planned should be compactcd to at Icast 90 perecnt of die maximum dry density(D4DD) per ASTM D 1557. • Struc[ural fill placed below proposed structures should be compacted to at least 9i percent of the MDD per ASTM D 1 SS7. • Structural till placed within 2 fcet of Ihc pavement or gra��cl driveway subbRade elevations should be compacted to at Ieast 95 percent of the MDD per ASTM D 1557. • Structural till placed for crushed surfacing base course below pavements should be compacted to at least 9� percent of the MDU per ASTM D l>j7. • Fill placed as preload fill should be compacted to the extcnt necessary to allow access for canstruction equipment. • Pill placed in landscape amas and other areas where no setdement-sensiti��e improvements will bc locatcd should be compacted tu at lcast 8� percent of tl�e MDD per ASTM D 15�7. The recommendations presented in this section are for the placement of swctural fill during the dry season. We recommend that a representative fiom our firm be present during placement of the strucmral fill. Our representative will evaluate subgrade conditions prior to placing till, perfortn in-place moismre density tests in the till to evaluate if the work is being done in accordance with the compaction specitications, and advise on any moditications to procedure that may b� appropriate for the prevailing conditions. FifcA'a.8937-OOJ-0G Y4gC 8 GEOENGINEEfl� OnnGcr ll.?006 � E-'. ( j1 - ` � ,,..,w �Y�cA � Yr� . � .�1 ��f' h ��" -.C`-a' ��1 .ii'd` �Y�'•�,0. � F ,a�{. �`:� tL+Yt ry -�• o {�4q�,, � '�'nti `4 ,_ e . � , .i. � .. .. � �C �*�...1,};`4'm- �f�... �� $ m'�.�.jx.a e,s:� . t %-�'l'+r..:$^ r . r'�._,- i +� . _ N � �4'^ ��,1 L., �„`_�b`4r