Loading...
HomeMy WebLinkAboutPermit Field Test & Inspection Report 2004-9-20 ld)stO ~lO.1tz; SIP-20-2004 DZ:Slpm Frcm-K & A Enilneerin., Inc +54H84-9358 T-795 P 002/007 F-952 ~ . K a A Engineering, Inc. P.O. Bal28624, E....... OR 87. 521 MIf'bt 11., Illite B. Ea..... OR .7. (&41) 184 .. Voice (141) 184-8868 FAX '__21,- Hayden Homes 2464 5W Glacier Place, SlfIte 110 Redmond, OR 97756 Subject: Quality assurance - house foundation pad construotion Jasper M$8dows SubdMsion - 2nd Addition Springl\8ld1 Oregon PmjecI: 74.04 PURPOSE AND SCOPE As 1'8qU98t8d. K & A Engineering. Inc, has complel8d mOnltoring the construction of IndMdual foundation pads at the subject new residentlalSUbdMSIon. 39 inDIVidual foundation pads were constructBd at the site and prepared ready for forming new foundations. Prior to construction. a Geotechnlcallnvestlgation1 was made of the subdivision to develop specific tecommsndattons for developing 1tIe site for IIs1dentl8l fou~atlonsr ~, and uuutIas. The purpose Of our IIfVic8s was to provide monitOl' constructlon of foundation padS to asstn1 that CONtnwtion crltet1a outlined In the geo18ctm1caJ Investigation was addressed. . 11118 report documents foundaUon pad construction and makes recommendations for suitability for residential foundation construcfIon. " FOUNDA11ON PAD EXCAYADON Gill. The foundation pads devetoped for this project are to BUpport cOIIVGntIonally framed rnidllntial structunIa supported by conventional cast-ln-pI8ee conCrotB $,"ad footings. Due to the slope or Ih8 SI8 most or the foundation pads WlI1 con&tructed In two or moro benohas, separated In grade by appl'm:/. ;ddy 1 to 2-f8et. FoundIdOa hill 1be Qeotecl'lnlcallnv88tklatlon (Bofre) had predicted that high plasticity sills or clays would underlie the site. eccavatlon for 1118 pada confirmed that in most of the foundation pads, 1I1ere was 1 to 3-feet t;If a gray. highly plastic, modllralflly stiff. and moist silt. In some locations the gray ell contained a significant amount of sub- rounded IgnBou8 cobbles, Thls silt was anan covered by 0.&.10 1.().feet of damp, very low..(fenslty peaty siltS. Weathered )'IIIlOW-tan ~us siltstone or sandstone was encountered underneath the plastic silts. 1 BOiRl AsaocIatBs, Inc.. Gs ;..",~:., lcaIlBYesIgaIlon for 1m Jasper Meadows kcond AdditiCII, Sprfngfleld, Oreoon. FtbnIIry 16, 2003. 8 'd Z8L9'oN S3~OH N30AYH ~dtt:Z 900Z 'g 'UBr $8P-~O-2004 02:31pm From-K & A En,ln88rln.. Ine +541-694-9358 . T-735 P OD91007 F-952 K & A EnafneerlnG, Ioc:. The gray plastic sills and gray plastic JIIt8 wfth oobblts were deepest through rITe western portion 01 the subdivision. IsoIat8d zones of gray plastic sltt or plastic silt with cobbles were also ellCount8l1d throughoUt 1f1e central and eastern portions or the eubdMslon. FaundlliaD Pad Gonatrucllon Because the depth and .ant of solis varied significantly across the subdlvlflon, ~h pad was evaluated IndlYldually to d8tlrmlna the proper depth of excavation and the amount 01 &elect fin to be placed in Ule mccavatlon. For many of th~ foundation pad8. the depth to weathered slRstone or sandstone was less than 2.feet and, In these cases. the foundation pads were excavated to bedtOCk, and grldad smooth, level, and free from lOose materfals. In ~ casH the baSe or the excavation was in two benches ssparated in grade from 1 to 2.feet Select aranular fill WU placed In the prepared excavation and brought to footing arndt:, In those al!aS of dMper gray plastic sUI, the sifts weAl removed to a minimum depth of 1 &-inche8 bBlow footing grade. The bottalTl$ 01 the eavatIons were graded smootn, level, and free from loose materials. In most cases the base of the excavation was In two benahas separated In grade from 1 to 2-fael Select granular no was placed in the ~ axcavatlon and brooght 10 footing grade. In aU case$ whenl peaty sllta were encountered, the peaty-silts were completely remavad frOm the foundallon area. ... ....., Grlmdar Fills Select granular fills conslst8d 01 a BUb-base mater1al and a baSe material. The 8IJb..base . .1 Ii!.. : rial was placed on 1h8 pl'8plfld subgrade in the foundatton pads and con9fBtBd 01 a S-1nch minus weU.grad8d quarry aggragatB. The _8 matet1al was placed over the sulJ-llase rock anti consI81Bd of a 11k1nph minus del1SfJ..graded quarry aggr&gat9. Both aooreoates wart produced at the Morse Bros. Quany In Sprlngtleld. l11a atJb.bac8 thIaknesI generally ranged from 610 12-inch88. Base rock ranged from 4 to 12-inches In 1hIckneaa. In a few aues (lots 33 through 39) tf1e sub-ba8e rock was elimInated and base rock was used exclUslV8ly for the aslect granular flU. The select granular fiUS were well compacted in 12.inch maximum lifts (loose) using a steel-wheeled VIbratOry roller. Water was applied 88 necessary to maintain optimum water content during compaction. DenIIty cd ScI8Cl8Rmll.. filla SUb-base The density of the Bub-base was evaluated by InSpBCtlon of placement melI10ds and field evalua1ton of water content. The density was considered adequate If passes by the large vibratory stael-drum roller did not leave VIslbIe markS In the sub-base agg~ at th8 edges of the drum BJ1d if the eoA water cont8nt appeared 10 be near opttmum as d8l8ImIned In the ftald. e 2 SqUH2lng a small amount of 118_ lIQDr8DlIlJ in the hand did not produce silJllificant free water and WOlJld f8I1'IaIn In a rellliYely uniform biI wtf10ut immediately failing apart. Project 74.04 Jasper Meadows Subdivision Phase II, Springfield, OR Page 2 Of 3 Client Hayden Homes ' september 20, 2004 V 'd l8L9'oN S3~OH N30AVH ~d9v:l 900l '9 'uer