HomeMy WebLinkAbout856 Torino Cir - Special Inspections/Engineering - 11/01/20174396 GREENFIELD DRIVE
WINDSOR, COLORADO 80550
(970) 545-3908 FAX (970) 663-0282
November 1, 2017
Columbine Health 14th Street, LLC
802 West Drake Road, Suite 101
Fort Collins, Colorado 80526
Attn: Mr. Bob Wilson (Bob.Wilson@columbinehealth.com)
Re: Construction Observation and Testing – Submittal No. 5
Columbine Residences – Torino Circle
Fort Collins, Colorado
EEC Project No. 1174094
Mr. Wilson:
As requested, during the period of September 25 through October 21, 2017, Earth Engineering
Consultants, LLC (EEC) personnel provided construction observation and testing services for the
proposed Columbine Residences project located at Torino Circle in Fort Collins, Colorado.
Those services were provided on a part-time/on-call basis and included observations of
foundation bearing subgrade soils for various buildings, observations of foundation reinforcing
steel for various buildings, and testing of cast-in-place concrete for the referenced project. The
results of the observation and testing services completed by EEC personnel during the referenced
period are included with this report.
Foundation Bearing Observations
EEC personnel visited the site on September 26 and October 5, 12, and 13, 2017, to observe the
foundation bearing subgrade soils for various buildings. On September 26, 2017, EEC personnel
observed the foundation alignments for Building 6 / AA (851 and 853 Torino Circle). At the
time of our site visit the foundation alignments had been excavated to approximate foundation
bearing elevations, approximately 2 to 3 feet below ground surface elevation. The bearing soils
exposed at the bottom of the foundations alignments, in general, consisted of apparent native
and/or engineered fill lean clay with variable amounts of sand. To evaluate the relative density
of the apparent native and/or engineered fill lean clay with variable amounts of sand, a DCP was
advanced an additional 30 inches below the exposed foundation bearing elevations. The DCP
was advanced at one (1) random location in the excavated foundation alignment areas. DCP
testing indicated the lean clay with variable amounts of sand was stiff to very stiff in consistency.
Earth Engineering Consultants, LLC
EEC Project No. 1174094
November 1, 2017
Page 2
On October 5, 2017, EEC personnel observed the foundation alignments for Building 8 / AD
(854 and 856 Torino Circle). At the time of our site visit the foundation alignments had been
excavated to approximate foundation bearing elevations, approximately 2½ to 3 feet below
ground surface elevation. The bearing soils exposed at the bottom of the foundations alignments,
in general, consisted of apparent native and/or engineered fill lean clay with variable amounts of
sand. To evaluate the relative density of the apparent native and/or engineered fill lean clay with
variable amounts of sand, a DCP was advanced an additional 30 inches below the exposed
foundation bearing elevations. The DCP was advanced at two (2) random locations in the
excavated foundation alignment areas. DCP testing indicated the lean clay with variable
amounts of sand was stiff to very stiff in consistency.
On October 5, 2017, EEC personnel also observed the foundation alignments for Building 5 /
DD (857 and 859 Torino Circle) and Building 6 / AA (851 and 853 Torino Circle). The
foundation bearing soils had been previously observed, however, due to weather events the
foundation bearing soils were reassessed. At the time of that visit, EEC personnel confirmed that
all standing water and mud was removed and the subgrade soils had been reworked, were stable,
and appeared consistent with previous observations. In addition, EEC personnel provided
observations of the slab-on-grade subgrade conditions for Building 3 / AA (869 and 871 Torino
Circle) and Building 4 / CE (863 and 865 Torino Circle). At the time of our visit approximately
4 to 6 inches of gravel were in place. EEC personnel provided visual observations of the areas
and determined the subgrade soils below the gravel layer was stable and the gravel and
underlying soils were not saturated.
On October 12, 2017, EEC personnel observed the foundation alignments for Building 7 / BE
(860 and 862 Torino Circle). At the time of our site visit the foundation alignments had been
excavated to approximate foundation bearing elevations, approximately 2½ to 3 feet below
ground surface elevation. The bearing soils exposed at the bottom of the foundations alignments,
in general, consisted of apparent native and/or engineered fill lean clay with variable amounts of
sand. To evaluate the relative density of the apparent native and/or engineered fill lean clay with
variable amounts of sand, a DCP was advanced an additional 30 inches below the exposed
foundation bearing elevations. The DCP was advanced at two (2) random locations in the
excavated foundation alignment areas. DCP testing indicated the lean clay with variable
amounts of sand was stiff to very stiff in consistency.
Earth Engineering Consultants, LLC
EEC Project No. 1174094
November 1, 2017
Page 3
On October 12 and 13, 2017, EEC personnel observed the foundation alignments for Building 9 /
FG (845 and 847 Torino Circle), 847 and 845 Torino Circle, respectively. At the time of our site
visits the foundation alignments had been excavated to approximate foundation bearing
elevations, approximately 3 to 3½ feet below ground surface elevation. The bearing soils
exposed at the bottom of the foundations alignments, in general, consisted of apparent native
and/or engineered fill lean clay with variable amounts of sand. To evaluate the relative density
of the apparent native and/or engineered fill lean clay with variable amounts of sand, a DCP was
advanced an additional 30 inches below the exposed foundation bearing elevations. The DCP
was advanced at two (2) random locations in the excavated foundation alignment areas. DCP
testing indicated the lean clay with variable amounts of sand was stiff to very stiff in consistency.
It is our understanding the upper 3 feet of site subgrade materials across the site were previously
over excavated, moisture conditioned and replaced. The observation and testing of the removed
and replaced overlot grading fill material was provided by Northern Colorado Geotech.
Based on the results of the outlined field observations and testing for the various buildings, the
bearing soils could be used for support of the footing foundations at the design maximum net
allowable total load soil bearing pressure of 1,500 psf as recommended in our Geotechnical
Exploration Report, EEC project number 1162080, dated September 8, 2016.
Care should be taken during construction to avoid disturbing the subgrade materials. Materials
that are loosened or disturbed by construction activities or materials that become dry and
desiccated or wet and softened should be removed and replaced or reworked in place prior to
placement of reinforcing steel/concrete.
Foundation Reinforcement and UFER Observations
During the referenced period, EEC personnel conducted site visits on October 5, 13 and 17,
2017, to perform visual observations of the reinforcing steel placed within Building 6 / AA (851
and 853 Torino Circle), Building 7 / BE (860 and 862 Torino Circle), Building 8 / AD (854 and
856 Torino Circle) and Building 9 / FG (845 and 847 Torino Circle) foundation elements at the
gridlines and/or locations as identified on the enclosed “color-coded/highlighted” site diagrams.
The horizontal and vertical reinforcement for cast-in-place foundation systems as indicated
Earth Engineering Consultants, LLC
EEC Project No. 1174094
November 1, 2017
Page 4
herein were completed in general accordance with the Spread Footing Schedule as presented on
Sheet S1.1 for the various building plans, as well as the details presented on Sheet S2.1 of the
project’s respective structural drawings.
Clearances and lap lengths, where applicable, were checked and appeared to meet the minimum
requirements. The horizontal and vertical reinforcement for the portions of the foundation
systems as noted herein and observed by EEC personnel on the dates indicated, appeared to be in
general accordance with details presented on the structural drawings prepared by Larsen
Structural Design, dated February 24, 2017.
In addition, Beacon Construction personnel requested that EEC provide a general observation of
the UFER grounding rod installation for Building 6 / AA, Building 7 / BE and Building 8 / AD,
which was installed during the foundation stem-wall reinforcement placement. EEC personnel,
during the reinforcement observation, noted two (2) additional approximately 20 foot sections of
#4 continuous horizontal rebar attached to the bottom #4 rebar of the stem-wall reinforcement,
which transitioned vertically approximately 5 feet to above the top of the foundation wall at each
building. The UFER grounding rods appeared to have been installed in general accordance with
typical standards of the industry installation procedures.
Testing of Cast-in-Place Concrete
During the referenced period, EEC personnel observed and tested Portland cement concrete
delivered to the site for placement as indicated on the enclosed daily reports for the referenced
project, (please refer to Set Nos. 7 through 9). Field testing performed on the plastic concrete
included slump, air content, unit weight and concrete temperature. The ambient air temperature
at the time of placement was also recorded. A minimum of five (4-inch diameter by 8 inches in
height) concrete test cylinders were cast from representative samples on each respective date for
laboratory curing and compressive strength testing. Results of the field and 7-day laboratory
compressive strength test results performed during the referenced period are included herein,
while the 28-day laboratory compressive strength test results will be provided as they become
available.
Reinforcing Steel Observation Diagram
Building 6 / AA (851 & 853 Torino Circle)
Columbine Residences - Torino Circle - Fort Collins, Colorado
EEC Project #: 1174094 Date: October 2017
EARTH ENGINEERING CONSULTANTS, LLC
Legend
Stem Wall
Reinforcement
Observation 10-17-17
Reinforcing Steel Observation Diagram
Building 7 / BE (860 & 862 Torino Circle)
Columbine Residences - Torino Circle - Fort Collins, Colorado
EEC Project #: 1174094 Date: October 2017
EARTH ENGINEERING CONSULTANTS, LLC
Footing Reinforcement
Observation 10-13-17
Legend
Stem Wall
Reinforcement
Observation 10-17-17
Reinforcing Steel Observation Diagram
Building 8 / AD (854 & 856 Torino Circle)
Columbine Residences - Torino Circle - Fort Collins, Colorado
EEC Project #: 1174094 Date: October 2017
EARTH ENGINEERING CONSULTANTS, LLC
Stem Wall
Reinforcement
Observation 10-13-17
Legend
Footing
Reinforcement
Observation 10-5-17
Reinforcing Steel Observation Diagram
Building 9 / FG (845 & 847 Torino Circle)
Columbine Residences - Torino Circle - Fort Collins, Colorado
EEC Project #: 1174094 Date: October 2017
EARTH ENGINEERING CONSULTANTS, LLC
Footing Reinforcement
Observation 10-13-17
Legend
Placement Date:
Placement Location:
Concrete Supplier:
Water Added on Site:
of
Required 28 Day Compressive Strength (psi):
B
Project Number:
EARTH ENGINEERING CONSULTANTS, LLC
REPORT OF CAST-IN-PLACE CONCRETE TESTS
60354449 Truck Number:
GENERAL INFORMATION
9212
Mix Code: 5304122 None
Foundation of Buildings 7 & 9, Walls of Building 8
Aggregate Industries Type of Placement: Pump
10/13/2017 Test No.: 7
Ticket Number:
Comments:
Yards: 40 80
3000 EEC Technician: AW
Batch Time: 1:07 PM Sample Time: 1:30 PM
FIELD TEST DATA
TEST RESULTS SPECIFICATIONS
Slump (in) ASTM C143 5"
Air Content (%) ASTM C231 6.5%
Unit Weight (pcf) ASTM C138 140.2 ----
Concrete Temperature (deg F) ASTM C1064 70 90° Max
Air Temperature at Placement (deg F) 76 ----
Comments:
COMPRESSIVE STRENGTH OF FIELD CAST TEST SPECIMENS (ASTM C39/C31)
Average
Maximum Cylinder Cylinder Compressive Compressive
Failure Strength Strength
Number Tested (days) (lbs) (in) (in) (in2) Type (psi) (psi)
Specimen Date Age Applied Load Height Diameter Area
7 10/20/17 7 27360 8 4 12.57 Shear 2180 2180
Project: Columbine Residences - Torino Circle
Aggregate Industries
Beacon Construction - Mr. Dillon Hinchley (dillon@beacon-con.com)
Beacon Construction - Mr. Chris Mahlum (chris@beacon-con.com)
Beacon Construction - Mr. Tyler Texeira (tyler@beacon-con.com)
1174094 Report Distribution:
Notify Contractor of Low 7 Day Breaks
Columbine Health Systems - Bob Wilson: Bob.Wilson@columbinehealth.com
Placement Date:
Placement Location:
Concrete Supplier:
Water Added on Site:
of
Required 28 Day Compressive Strength (psi):
B
Project Number:
Aggregate Industries
Beacon Construction - Mr. Dillon Hinchley (dillon@beacon-con.com)
Beacon Construction - Mr. Chris Mahlum (chris@beacon-con.com)
Beacon Construction - Mr. Tyler Texeira (tyler@beacon-con.com)
1174094 Report Distribution:
Columbine Health Systems - Bob Wilson: Bob.Wilson@columbinehealth.com
Project: Columbine Residences - Torino Circle
8 10/24/17 7 35000 8 4 12.57 Shear 2790 2790
Failure Strength Strength
Number Tested (days) (lbs) (in) (in) (in2) Type (psi) (psi)
Specimen Date Age Applied Load Height Diameter Area
Average
Maximum Cylinder Cylinder Compressive Compressive
----
Comments:
COMPRESSIVE STRENGTH OF FIELD CAST TEST SPECIMENS (ASTM C39/C31)
Slump (in) ASTM C143 4"
Air Content (%) ASTM C231 5.1%
Unit Weight (pcf) ASTM C138 140.4 ----
Concrete Temperature (deg F) ASTM C1064 74 90° Max
Air Temperature at Placement (deg F) 55
FIELD TEST DATA
TEST RESULTS SPECIFICATIONS
Comments:
Yards: 10.5 60
3000 EEC Technician: JB
Batch Time: 10:13 AM Sample Time: 11:00 AM
Mix Code: 5304122 None
Building 6 Walls
Aggregate Industries Type of Placement: Pump
10/17/2017 Test No.: 8
Ticket Number: 60354522 Truck Number:
GENERAL INFORMATION
683
EARTH ENGINEERING CONSULTANTS, LLC
REPORT OF CAST-IN-PLACE CONCRETE TESTS
Placement Date:
Placement Location:
Concrete Supplier:
Water Added on Site:
of
Required 28 Day Compressive Strength (psi):
B
Project Number:
EARTH ENGINEERING CONSULTANTS, LLC
REPORT OF CAST-IN-PLACE CONCRETE TESTS
60354532 Truck Number:
GENERAL INFORMATION
690
Mix Code: 5304122 None
Building 7 Walls
Aggregate Industries Type of Placement: Pump
10/17/2017 Test No.: 9
Ticket Number:
Comments:
Yards: 52.5 60
3000 EEC Technician: JB
Batch Time: 12:05 PM Sample Time: 1:00 PM
FIELD TEST DATA
TEST RESULTS SPECIFICATIONS
Slump (in) ASTM C143 3.5"
Air Content (%) ASTM C231 5%
Unit Weight (pcf) ASTM C138 141.2 ----
Concrete Temperature (deg F) ASTM C1064 72 90° Max
Air Temperature at Placement (deg F) 71 ----
Comments:
COMPRESSIVE STRENGTH OF FIELD CAST TEST SPECIMENS (ASTM C39/C31)
Average
Maximum Cylinder Cylinder Compressive Compressive
Failure Strength Strength
Number Tested (days) (lbs) (in) (in) (in2) Type (psi) (psi)
Specimen Date Age Applied Load Height Diameter Area
9 10/24/17 7 31590 8 4 12.57 Shear 2510 2510
Project: Columbine Residences - Torino Circle
Aggregate Industries
Beacon Construction - Mr. Dillon Hinchley (dillon@beacon-con.com)
Beacon Construction - Mr. Chris Mahlum (chris@beacon-con.com)
Beacon Construction - Mr. Tyler Texeira (tyler@beacon-con.com)
1174094 Report Distribution:
Columbine Health Systems - Bob Wilson: Bob.Wilson@columbinehealth.com