3030 Lexington Ave - Soils testing reportY
aMERICAN
t 1 ENGIfi'EERING
o TESTING, INC,
RFPORT OF PROJECT TESTING SERV]
PROJECT: REPORTED TO:
LEXINGTON COMMERCE CENTER OPUS CORPORATION
LONE OAK ROAD & LEXINGTON AVE. 800 OPUS CENTER
EAGAN, MINNESOTA 9900 BREN ROAD EAST
MINNETONKA, MN 55343
AET JOB NO.: 97-942
Q'rC. .3. 19y/
ATTN: MR. JEFF MERTENS
DATE: DECEMBER 12, 1997
INTRODUCTION
This report presents the results of the project testing services we have conducted for the Lexington
Commerce Center in Eagan, Minnesota. Our services were conducted on an internrittent basis
as authorized on August 4, 1997, by Mr. Jeff Mertens from Opus Corporation. The scope of our
work was lirnited to the following:
• Observe the soils in the bottoms of the mass building excavation and foundation
excavations for the building.
• Perform soil compaction tests in fill placed for the project.
• Perform on-site testing of plastic concrete; including slump tests, air content tests, and
casting concrete test cylinders.
• Perform compressive strength testing of concrete test cylinders.
• Observe welded and bolted connections for the structural steel frame, steel joists, and roof
deck.
• Summarize the results of our services in a written report.
CONSULTANTS
a GEOTECHNICAL
o MATERIALS
o ENVIRONMENTAL
DEC 16 _1997
'AN AFFIFMhTIVE ACTION EMPLOYER' '
2102 Unlversity Ave. W. . SL Paul, MN 55114 . 612-659-9001 . Fax 612-659-1379
Duluth . Mankato . Rochester . Wausau
k.
AET /i97-942 - Page 2
PROJECT INFORMATION
We understand the project will be a new office and warehouse building. We further understand
that the huIlding wiil:
• Have one above-grade level, supported on-grade.
• Have approlcimate overall dimensions of 160' by 570'.
• Be constructed using precast concrete wall panels, a structural steel frame, and a steel joist
supported metal deck roof.
• Be supported by spread footings designed using an allowable soil bearing pressure no
greater than 3,000 pounds per square foot (psfl.
• Have a finished floor slab elevation of 877.5.
• Have bottom-of-footing elevations of about 873'/z to 871'h for peruneter footings and
about 875 to 876 for interior footings.
• Have tolerance to total building sett]ements of up to 1", and differential settlements of up
t0 1z°.
• Be constructed in accordance with applicable building code requirements.
Please note that deviations from the above design information could necessitate altering our
conclusions and recommendations. Contact us if the information stated is different from the actual
design.
Building location and elevation information obtained at the site, and presented in this report, was
taken from building corner offset stakes and grade stakes provided by the Opus Corporation
surveyors.
AET #97-942 - Page 3
BACKGROUND INFORMATION
Previousiy, a subsurface exploration program was performed at the referenced site by our firm.
The results were presented in our November 22, 1996, report (AET #96-2709). Refer to thai
report for pertinent background information and for our recommendations to prepare the building
area for structural support.
EXCAVATION OBSERVATIONS
We observed the soils exposed in the bottoms of the mass building excavation and individual
foundation excavations during the period from September 3, 1997 to 5eptember 24, 1997. We
were not present at the site on a full-time basis. Our services consisted of several site visits,
coordinated with Opus Corporation, which allowed us to observe the mass building excavation
bottom in roughly the southern one-half of the building, and the foundation excavation bottoms
in roughly the northern one-half of the building. Besides observing the soils exposed we
conducted shallow hand auger borings and hand cone penetrometer readings in the bottoms of the
excavation. The soIls encountered were classified in general accordance with ASTM: D2488.
Estimates were made of the suength properties of the soils based on their resistance to
advancement of the hand auger and from the hand cone penetrometer readings.
We observed that the soils exposed in the bottom of the mass excavation for the building and the
foundation excavations consisted of naturally deposited alluvial sands, silty sands, and clays; or
glacial till clays and clayey sands. Based on our observations, hand auger borings, and hand cone
penetrometer readings, we judged these soils suitable to support the fill and structural loads. 'The
bottoms of the excavations ranged from about elevation 846 in the south end of the building to
about 877 in the north end of the 6uilding.
AET #97-942 - Page 4
Since a portion of the excavation for the building temunated below bottom-of-footing elevation,
we recommended a minimum 1:1 lateral oversizing of the excavation bottom. Based on the offset
staking and elevation information provided at the site, it is our_ judgment that the excavation
bottom was provided with the recommended oversizing.
C'nMPAC'TION TESTING OF FILL
During the period from September 3 to November 3, 1997, we conducted a totalrof 74 soil density?
tests in the fill placed in the building and surrounding site azea. The density tests were compared
to the laboratory Standard Proctor maximum dry density (ASTM: D698) to arrive at a percent
compaction level for each test. ,The test results indicate the recommended compaction levels were ,
finally met or exceeded at the locations and elevations tested. The test results were submitted
previously, under sepazate cover.
G
CONCRFTE TESTIN
We performed testing of the plastic concrete as it was placed for the slab-on-grade. Our services
included the following:
• Measure the slump of the concrete.
• Measure the percentage of entrained air.
• Detertnine the temperature of the concrete.
• Cast 6" diameter by 12" high test cylinders.
All testing was performed in accordance with current ASTM procedures. The results of the on-
site testing were presented in our Reports of Plastic Concrete Testing, which were issued under
separate cover. ?The results of our tests generally satisfied the project specifications.?
AET #97-942 - Page 5
We have also performed compressive strength testing of test cylinders cast for concrete placed for
the footings and floor slabs. The results of these tests were presented in our Reports of
Compressive Strength of Cylindrical Concrete Specnnens, copies of which were also previously
submitted under separate cover. The majority of the cylinders have been tesied at the 28-day age.
These test results have met or exceeded the 28-day design compressive suength. Some cylinders
have not yet been tested at the 28-day age. :The results of the 7-day tests indicate they should meet :
the design strength (based on typical strength-age relationships). )The results of these tests will
be forwarded in the future, as they become avaIlable.
OBSERVATIONS OF WELDED AND BOLTED CONNECTIONS
We observed the high-strength bolted connections and welded connections for the building. The
bolted connections were for the structural steel frame, and the welded connections included bar
joist to frame welds, and deck welding. The results of our testing were presented in our Report
of Welded and Bolted Connection Observations (dated November 10, 1997), which was previously
submitted under separate cover. ?. As stated isthe report, -ttie field welded and bolted connections ?
were judged Yo satisfy the requirements of the project specifications and the referenced codes. ?
.L(051 TRE
To protect the client, the public and American Engineering Testing, Inc., this report (and all
supporting information) is provided for the addressee's own use. No representations are made
to parties other than the addressee.
Our services on this project have been conducted to those standards considered normal for
services of this type at this time and location. Other than this, no warranry, either express or
implied, is intended.
SIGNATi_TRES
Report Prepared By:
AET #97-942 - Page 6
Report Reviewed By:
McCarthy, PE
Principal Engineer
MN Reg. #16688