Report Mr. Cory Borne March 12, 2020 of *.
Site Inspection Page 12
10635 SW Cook Ln
Tigard, OR
•
on the upper shaft onto the anvil. The underlying soil strength is determined by measuring the
penetration of the lower shaft into the soil after each hammer drop. The number of drops required
for a penetration of 4" is then recorded and converted to an equivalent SPT N-values which is
reported on the attached boring log (DC-1).
The DCP boring extended to a depth of thirteen feet (13'-0") below grade. The upper six feet (6'-
0")of soil consists of soft to medium stiff material. Between six feet (6'-0")and nine feet(9'-0"), a
stiff to very stiff layer of material was found. Between nine feet (9'-0") and thirteen feet(13'-0"), a
medium stiff to stiff layer of material was found. The DCP boring log (DC-1) is attached to this
report.
A test pit was excavated on March 4, 2020 adjacent to the footing. The test pit extended to a
depth of three feet (3'-0") below the foundation grade beam. The upper two feet (2'-0") of soil
consisted of soft to medium soft brown clayey silt, followed by a layer of medium stiff to stiff brown
clayey silt, which was encountered to the termination depth at three feet(3'-0").
RECOMMENDATIONS
It is our opinion that the settlement is the result of improper foundation drainage and/or undersized
foundations.We understand that helical piles are proposed to underpin portions of the north,east,
and west sides of the residence.
A hydraulic torque driver head is used to install the helical pile. Advancement of the pile will
continue until the minimum installation torque is achieved as specified by the torque correlation
method to support the allowable design loads of the structure using a torque factor.
We recommend that the proposed piles achieve a minimum embedment depth of seven (7)feet.
However, it is anticipated the actual pile embedment depth may be greater. The repair work will
not interfere with the existing lateral support conditions. Therefore, there are no lateral design
concerns.
Maintaining uniform moisture around the foundation is very important. The landscape grades
around the residence should be maintained to slope away from the residence where required.
The landscape grades should slope away from the foundation at a minimum of 1/2" per foot for six
(6'-0)feet.The top soil should extend a minimum of one(1'-0)foot above the bottom of the footing
and should not extend above four(4")inches below the bottom of the siding.All new fill soil should
be clayey sand with a minimum Plasticity Index (PI) of twenty-five (25). Watering the soil around
the foundation is also important during dry periods to help maintain uniform moisture in the soil.
This report is for the sole use of Ram Jack West and their design consultants for the foundation
repair at the referenced site. Northwest Engineering Group assumes no responsibility or liability
for any engineering judgement, inspection or testing performed by others outside the scope of
this report. Our services do not include any survey or assessment of contamination or potential
contamination of the soil or ground water by hazardous or toxic substances. No warranty is
expressed or implied by this report.
This concludes this report. If I can be of further assistance or should you have any questions
about this report, please do not hesitate to contact me.
P.O. Box 10393/ Eugene, OR 97440/541.393.7363/WWW.NWENGGROUP.COM
4 Mr. Cory Bome March 12, 2020
Site Inspection Page 13
10635 SW Cook Ln
Tigard, OR
Sincerely, /7
4, DPROpSs
OINEc'P %
9f
,4�j//88
1. Za 01.
'fOE STEER.
EXPIRES: 6943Q�
Sean Morrison, E.I.T. Charles Steffensmeier, P.E.
Engineering Technician Civil Engineer
Attachment: Site Plan (SK-0)
Dynamic Cone Penetrometer Test(DC-1)
P.O. Box 10393/ Eugene, OR 97440/541.393.7363/WWW.NWENGGROUP.COM
, ' ►.
98.1' +/- .
i
DETACHED
GARAGE
i I
I I
10635 SW COOK LN
+ ++
I _ TP-1 DC-1 I �.
all.
�r r
I
Il
14.4' +/-
I I
ENTRY
PROPERTY ccd"' I
(!"'LINE
L _ _ _ _1
98.1' +/-
S4,R�D PROFeSS SITE PLAN
�v, 101 NFF io
I..
58..• r
1/7 Am TREE PRESERVATION NOTES:
{ S4F Q 2p�a, „ 1.ALL HOLES ARE EXCAVATED NEXT TO THE
STRUCTURE FOUNDATION
✓9 sTEFO- NORTH 2.THE TOTAL AREA OF EXCAVATED HOLES<25 SOFT
EXPIRES: zed/el
NORTHWEST CORY BOME SHEET:
10635 SW COOK LN SK"O
ENGINEERING GROUP TIGARD, OR
P.O.BOX 10393 SCALE: DATE:
EUGENE,OR 97440 (541)393-7363 1130"=11-0 03/12/2020
.. •
WILDCAT DYNAMIC CONE LOG Page 1 of 2
North West Engineering
P.O. Box 10393 PROJECT NUMBER: 04117
Eugene, OR 97440 DATE STARTED: 03-04-2020
DATE COMPLETED: 03-04-2020
HOLE#: DC-1
CREW: Sean Morrison SURFACE ELEVATION:
PROJECT: Con Borne WATER ON COMPLETION:
ADDRESS: 10635 SW Cook Lane HAMMER WEIGHT: 35 lbs.
LOCATION: Tigard. OR CONE AREA: 10 sq. an
BLOWS RESISTANCE GRAPH OF CONE RESISTANCE 1 TESTED CONSISTENCY
DEPTH PER 10 an_ Kg/an2 0 50 100 15( N NON-COHESIVE COHESIVE
- 4 17.8 5 LOOSE MEDIUM STIFF
- 4 17.8 5 LOOSE MEDIUM STIFF
- 1 ft 6 26.6 7 LOOSE MEDIUM STIFF
- 6 26.6 7 LOOSE MEDIUM STIFF
- 5 22.2 6 LOOSE MEDIUM STIFF
- 2 II 4 17.8 5 LOOSE MEDIUM STIFF
- 3 13.3 ••• 3 VERY LOOSE SOFT
- 4 17.8 5 LOOSE MEDIUM STIFF
- 3 ft 5 22.2 6 LOOSE MEDIUM STIFF
- 1 m 4 17.8 5 LOOSE MEDIUM STIFF
- 6 23.2 6 LOOSE MEDIUM STIFF
- 4 ft 5 19.3 5 LOOSE MEDIUM STIFF'
- 7 27.0 7 LOOSE MEDIUM STIFF
- 6 23.2 6 LOOSE MEDIUM STIFF
- 5 ft 6 23.2 6 LOOSE MEDIUM STIFF
- 5 19.3 5 LOOSE MEDIUM STIFF
- 6 23.2 6 LOOSE MEDIUM STIFF
- 6 ft 10 38.6 11 MEDIUM DENSE STIFF
- 12 46.3 13 MEDIUM DENSE STIFF
- 2 m 13 50.2 14 MEDIUM DENSE STIFF
- 7 ft 16 54.7 15 MEDIUM DENSE STIFF
- 14 47.9 13 MEDIUM DENSE STIFF
- 23 78.7 22 MEDIUM DENSE VERY STIFF
- 8 ft 16 54.7 15 MEDIUM DENSE STIFF
- 20 68.4 19 MEDIUM DENSE VERY STIFF
- 13 44.5 12 MEDIUM DENSE STIFF
- 9 ft 16 54.7 15 MEDIUM DENSE STIFF
- 12 41.0 11 MEDIUM DENSE STIFF
- 13 44.5 12 MEDIUM DENSE STIFF
- 3 m 10 ft 12 41.0 11 MEDIUM DENSE STIFF
- 14 42.8 12 MEDIUM DENSE STIFF
- 12 36.7 10 LOOSE STIFF
- 10 30.6 8 LOOSE MEDIUM STIFF
- J1uf 12 36.7 10 LOOSE STIFF
Gy£p •RQF 33.7 9 LOOSE STIFF
�s 30.6 8 LOOSE MEDIUM STIFF
f"• NEF, spy 42.8 12 MEDIUM DENSE STIFF
- }� 5 Yr 45.9 13 MEDIUM DENSE STIFF
88' ,! 16 49.0 13 MEDIUM DENSE STIFF
if ft ,/� 49.0 13 MEDIUM DENSE STIFF
4 ! • - -.• a
'PeF v F 30 20�°' t`4 7 CAW ow,ne u+slwstIwc w_ si.Xls
5
S�Oe SrEFF*N
EXPIRES: di'4��f/