1629 Lena Ct - Soils testing letter?-
CINSTANT TESTING COMPANY
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7125 West 1'6th Street • Suite 500 • Savage. YIN 5i;78
PHONE: 9?;2-890-7166 • FAX: 952-390-585"
June 12, 2003
'IWCzr4?
??kAttn: Andy JU??
Manley Land Development ??0?
2113 Cliff Drive
Eagan, Minnesota 55122
RE: Inspection - Centennial Ridge 2nd Addition
Eagan, Dakota County, Minnesota
As requested, a site visit was conducted on June 10, 2003 to
evaluate soil consolidation within graded pads for commercial
buildings #1 and #2 of the Centennial Ridge 2nd Addition. A
grading and construction plan prepared by Pioneer Engineering
Mohagen Hansen Architectural Group, dated March 19, 2003 was
provided prior to the inspection. Also referenced, subsurface
geotechnical report #00004 dated January 25, 2000 provided by
Test Drilling Company.
35th
ANNIVERSARY
2003
and
Allied
our observations, and data provided by the soil borings, indicates
quantities of undocumented fiii, primarily within the northeast
section of the development. A grade stake, located near the NE
corner of building pad #2, indicated a existing elevation of 947.0.
Based on topographic elevations provided by the preliminary grading
plan and proposed building elevations of 948.0 and 949.0, we would
conclude that recent grading has added 3 1/2 to 4 feet of fill to
the building pads.
To evaluate the consolidation and relative loadbearing capacity of
the inpiace sui:s, dynamic cc:e per?tromete: tests were conducted
approximately 25 feet on center from the end of each pad. Buil3ing
pad #1:-"test A" (west end), "test B" (east end), building pad #2:
"test C" (north end) and "test D" south end. The dynamic cone
penetrometer (DCP), uses a eight kilogram (17.6 pound) hammer to
drive a 20 millimeter diameter conical point into the soil, with the
penetration recorded in millimeters per blow.
At the referenced locatians, the DCP was advanced a total of:
test "A"- 641 millimeters (25.2 inches), test "B" - 841 millimeters
(33.1 inches), test "C" - 1476 millimeters (42.4 inches) and test
"D"- 686 millimeters (27.0 inches). A composite, per blow,
penetration average of 32.2 MM, 30.0 MM, 65.2 MM and 24.7 MM
respectively was racorded. Our experience with the DCP in similar
soils to those at the site, would indicate a average penetration N-
ti
value of N-10.5 for tests "A" &"B", (bldg #1) and N-4.5 test "C" &
N-12.0 test "D" (bldg #2). This N-value, is an empirical
relationship we have established to equate the dynamic cone data to
the more familiar blows per foot (BPF) standard penetration soii
boring test. Based on this data, we would predict a relative
loadbearing capacity of 1500 PSF within the zone penetrated for test
"C" (north end bldg pad #2), which indicates a DCP penetration value
greater than 50 MM per blow. The remaining tests conducted,
indicate a loadbearing capacity of 3500 PSF.
As the referenced tests represent a limited evaluation of soil
consolidation within the building pads, It is recommended that the
soil conditions be reviewed at footing elevation during
construction. We wouid expect the loadbearing capacity to improve
or meet the target capacity of 2500 PSF, for the north end of
building #2, when excavated to frost footing elevation.
jincerely,
Instaryt-Zesting Company
3 'arp-S)Eand3 s h
Seniq? Inspect
Chg: #605 - ?,/Hours / #306 - 4 (DCP) / #612 - 22 Miles