HomeMy WebLinkAboutSUB201400101 Soil Report 2018-06-19underhilI ENGINEERING
geotechnical I geothermal I geoconstruction
Letter of Transmittal
June 19, 2018
Mr. John Anderson, PE, Civil Engineer II
Community Development Dept.
County of Albemarle, Virginia
401 McIntire Road
Charlottesville, VA 22902-2702
Subject: Documentation Regarding Earthwork and Pavement Subgrade Testing
Services, Hollymead Towncenter Block C4, Albemarle County, Virginia
(Underhill Engineering Project No. 16009.02)
(Albemarle County RE: SUB2014-00101)
Dear Mr. Anderson:
Underhill Engineering, LLC (Underhill) is pleased to present this transmittal consisting of documentation
regarding Earthwork and Pavement Subgrade Testing services. This transmittal includes daily field
records, soil laboratory Proctor data, Underhill's California Bearing Ratio (CBR) Testing report dated
March 15, 2017, and Underhill's letter dated March 7, 2018, summarizing the services provided. This
information is provided as requested by our client, Mr. Katurah Roell, copied here.
Note that Underhill's March 15, 2017 report includes a figure indicating the approximate test locations
where we excavated through the existing base course to obtain the soil samples for the CBR tests. Base
course thickness observed at the test locations met the required aggregate base course thickness as
indicated in the Dominion Engineering project documents last revised December 17, 2013.
T: 434.531.2565
327 W. Main Street, Suite 2, Charlottesville, VA 22903
underhillengineering.com
Underhill has endeavored to complete the services identified herein in a manner consistent with that
level of care and skill ordinarily exercised by members of the profession currently practicing in the same
locality and under similar conditions as this project. No other representation, express or implied, is
included or intended, and no warranty or guarantee is included or intended in this report.
Sincerely,
UNDERHILL ENGINEERING, LLC
r O. Christopher Webster, PE
z e ors 2018.06.19
20:25:32 -04:00
O. Christopher Webster, PE
Principal
Exhibits:
1. Moisture Density Relationship, Sample 1, 21A Dense -Graded Aggregate Base Course
2. Compaction Test Report, 4-11-16 through 4-15-16
3. Compaction Test Report, 5-27-16
4. Summary of Laboratory Testing, Samples S-1, S-2, and S-3
S. California Bearing Ratio (CBR) Testing Report dated 3-15-2017 (9 pages)
6. Letter Regarding Services Provided and Suitability of Pavement Section dated 3-7-18
cc: Mr. Katurah Roell- Town Properties, LLC
Project 16009.02 / June 19, 2018 2 Underhill Engineering, LLC
134.0
133.0
132.0
131.0
130.0
WON
U
Q
>-128.0
U5
z
w
}127.0
ry
1 126.0
125.0
124.0
123.0
122.0
121.0
3
\
\
\
\
\
\
\
\
\
\
\
5 7 9 11 13
WATER CONTENT, %
Sample Description: DENSE GRADED AGGREGATE, contains Assumed Specific Gravity:
crushed stone, gray Uncorrected Max. Dry Density (pcf)
Uncorrected Opt. Moisture (%):
15
2.76
130.4
8.8
Sample Source: Sample 1
Test Methods: ASTM D698 Method C Corrected Max. Dry Density (pcf): 133.6
Oversize Fraction Sieve Size: 3/4 in. Corrected Opt. Moisture (%): 8.1
Percent Oversized Retained: 10%
Liquid Limit (LL): NP Comments:
Plasticity Index (PI): NP Borrow Source: Rockydale Quarry, Albemarle
% Retained #4 Sieve: County, VA
% Passing # 200 Sieve: Date: 4-20-16 Reviewed By: DS
MOISTURE DENSITY RELATIONSHIP
Schnabel Project: Underhill Engineering
16009.02
E N G I N E E R I N G Charlottesville, VA
Contract: 15643010 Testing Lab: CVILL
Project Name:
Project Number:
Rep:
Gauge ID Number:
Dates:
Hollymead Town Center - Block 4
15643010
J. Bossinger, B. Cathey
I, Q
April 11 - 15, 2016
Field Density Test Summary
Test Date:
Density Standard:
Moisture Standard:
Lab Reference:
Optimum Moisture (%):
Maximum Dry Density:
95% of Maximum Dry Density
04/11/16
04/15/16
2009
1915
679
617
1
2
8.1
16.4
133.E
109.6
126.9
104.1
Test
Number
Date Tested
Elevation
(ft)
Probe Depth
(inches)
Lab Ref.
Wet Density
(PCF)
Moisture
Content (%)
Dry Density
(PCF)
Maximum
Dry Density
(PCF)
Percent
Compaction
(%)
Remarks / Location
1
04/11/16
583
12
2
-
15.5
-
-
-
Over Sanitary Sewer in Laurel Pk Ln, STA 0+20
as shown in profile on Drawing SP7.
Density not recorded due to crushed stone and
construction debris mixed with soil.
2
04/11/16
583
12
2
1.
_
3
04/11/16
585
12
2
15.6
4
04/11/16
586
12
2
17.0
-
5
04/11/16
587
12
2
17.0
-
6
04/15/16
598
12
1
139.2
4.5
133.2
133.6
99.7%
Over 8" W in Laurel Pk Ln, North of MH5
7
04/15/16
594
12
1
134.4
3.6
129.7
133.6
97.0%
Over 8" W in Laurel Pk Ln, North of MH4
Lab Reference Key:
Dense -graded aggregate, gray, imported from Rockydale Quarry (Standard Proctor)
On -site soils visually classifying as Sandy Silt (ML) contains mica and gravel, brown (One -Point Proctor)
Page 1 of 1
Project Name:
Project Number:
Rep:
Gauge ID Number:
Dates:
Hollymead Town Center - Block 4
15643010
N. Silman
X
05/27/16
Field Density Test Summary
Test Date:
Density Standard:
Moisture Standard:
Lab Reference:
Optimum Moisture (%):
Maximum Dry Density:
95% of Maximum Dry Density
Test
Number
Date Tested
Elevation Elevation
(ft)
Probe Depth
(inches)
Lab Ref.
Wet Density
(PCF)
Moisture
Content (%)
Dry Density
(PCF)
Maximum
Dry Density
(PCF)
Percent
Compaction
(%)
Remarks / Location
8
05/27/16
583
10
1
137.4
6.6
128.8
133.6
96.4
Over 24" HDPE STA -0+15
between EX ST-61 and EX ST-62
on Laurel Park Lane at Timberwood Blvd.
9
1 05/27/16
584
12
1
1 137.9
6.5
129.5
133.6
96.9
10
05/27/16
585
10
1
137.2
6.3
129.6
133.6
97.0
Lab Reference Key:
Dense -graded aggregate, gray, imported from Rockydale Quarry (Standard Proctor)
Page 1 of 1
appendix
Summary Of Laboratory Tests
Sheet 1
of 1
Project
Number:
Sample
y
�
-_
Depth
c
w
>, a
d
Boring
ft
Sample
Description of Soil
R
0
d
o
N
\
3 \
Ui
o
N
No.
Type
Specimen
H e
H rn
a
E"
c w
Elevation
H o
H o
r
E w
E
o o
a
>
ft
y
aw
av
0
x c
- c
c
V
co
_
H
e z°
a z°
e z
�o
0U
UU
Ua
U
0.0- 0.0
SILTY SAND (SM), fine to coarse grained
S-1
Bulk
sand, contains rock fragments and mica,
RICH
43.1
65.8
6.9
107.5
17.3
17.2
107.0
0.3
12.9
red -brown (Visual)
0.0
SILTY SAND (SM), fine to coarse grained
S-2
Bulk
sand, contains rock fragments and mica,
RICH
36.8
59.4
8.5
112.9
15.3
15.3
111.7
0.0
18.5
red -brown (Visual)
0.0
SILTY SAND (SM), fine to coarse grained
S-3
Bulk
sand, contains rock fragments and mica,
RICH
43.0
61.9
10.5
108.0
16.8
15.4
111.6
0.0
18.5
red -brown (Visual)
Notes: 1. Soil tests in general accordance with ASTM standards.
2. Soil classifications are in general accordance with ASTM D2487(as applicable), based on testing indicated
and visual
Sch n
a b e!
classification.
12
3. Key to abbreviations: NP=Non-Plastic; -- indicates no test performed
E N G I N E
E R I N G
Project:
Hollymead Town Center
16009.02
Albermarle County, VA
underhilI ENGINEERING
geotechnical I geothermal I geoconstruction
March 15, 2017
Mr. Katurah Roell
Town Properties, LLC
325 Barracks Hill
Charlottesville, VA 22901
Subject: California Bearing Ratio (CBR) Testing, Hollymead Towncenter
Block C4, Albemarle County, Virginia (Underhill Engineering
Project No. 16009.02)
Dear Mr. Roell:
Underhill Engineering, LLC (Underhill) is pleased to present this report, summarizing the
results of California Bearing Ratio (CBR) testing for this project. These services are provided in
accordance with Underhill's Services Agreement with you dated March 1, 2016, and your
authorization of January 21, 2017.
Laboratory Test Results
Three bulk samples were retrieved by Underhill from on site for soil laboratory testing. The
approximate sample locations are shown in Figure 1. Soil laboratory testing assigned by
Underhill consisted of the following:
■ Three gradation tests (ASTM D422).
■ Three Standard Proctor tests (ASTM D698).
■ Three California Bearing Ratio tests (VTM-8).
A summary of the soil laboratory test results, gradation curves, and moisture -density
relationships follows the text of this report. CBR tests results varied from 12.9 to 18.5 with zero
to 0.3 percent swell. We understand a design CBR value of 10 was considered for the design
pavement section. The as -tested CBR values exceed this design value.
Underhill has endeavored to complete the services identified herein in a manner consistent
with that level of care and skill ordinarily exercised by members of the profession currently
practicing in the same locality and under similar conditions as this project. No other
representation, express or implied, is included or intended, and no warranty or guarantee is
included or intended in this report.
T: 434.531.2565
108 South First Street, Charlottesville, VA 22902
underhillengineering.com
Thank you for the opportunity to provide our services. If you have any questions or require
additional information, please do not hesitate to contact me.
Sincerely,
UNDERHILL ENGINEERING, LLC
O. Christopher Webster, PE
Principal
Exhibit A:
Soil Laboratory Test Results
Project 16009.02 / March 15, 2017 2 Underhill Engineering, LLC
Soil Laboratory Test Results
Figure 1: Location Plan
Summary of Soil Laboratory Tests
Gradation Curves (1 sheet)
Moisture -Density Relationships (3 sheets)
Project 16009.02 / March 15, 2017 Underhill Engineering, LLC
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Summary of Soil Laboratory Tests
Sample No.
S-1
S-2
S-3
Sample Type
BULK
BULK
BULK
Description,
SILTY SAND (SM)
SILTY SAND (SM)
SILTY SAND (SM)
Symbol USCS
(visual)
(visual)
(visual)
% Passing No.
200 Sieve
43.1
36.8
43.0
% Passing No.
40 Sieve
65.8
59.4
61.9
% Passing No.
4 Sieve
6.9
8.5
10.5
Max. Dry Density
(pcf)
107.5
112.9
108.0
Optimum
Moisture
17.3
15.3
16.8
Content (%)
CBR Value
12.9
18.5
18.5
(soaked)
Swell (%) il
0.3
Zero
Zero
Testing provided by Underhill's subconsultant laboratory, Schnabel Engineering
Project 16009.02 / March 15, 2017 Underhill Engineering, LLC
U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS I HYDROMETER
n 1 1/9 4 R in in in ZZn inn 9nn
100
95
90
85
80
75
70
65
x
60
(D
w 55
m 50
ry
w 45
z
LL
1.- 40
z
w
U 35
Of
w
0 30
25
20
15
10
5
0
100 10 1 0.1
GRAIN SIZE IN MILLIMETERS
0.01 0.001
COBBLES
GRAVEL
SAND
SILT OR CLAY
coarse fine
coarse medium fine
Specimen Sample Description LL PL PI Cc Cu
N SILTY SAND (SM), fine to coarse grained sand, contains rock
o0 S-1 0.0 ft fragments and mica, red -brown (Visual)
0
N m S-2 0.0 ft SILTY SAND (SM), fine to coarse grained sand, contains rock
fragments and mica, red -brown (Visual) -- -'
a
a SILTY SAND (SM), fine to coarse grained sand, contains rock
WE
♦ S-3 0.0 ft fragments and mica, red -brown (Visual)
Specimen
Test Method
Testing Lab
D100
D60
D30
D10
%Gravel
%Sand
%Silt
%Clay
•
S-1
0.0 ft
ASTM D422
RICH
38.1
0.25
--
--
6.9
50.0
43.1
a
o m
S-2
0.0 ft
ASTM D422
RICH
64
0.45
--
--
8.5
54.7
36.8
Q ♦
S-3
0.0 ft
ASTM D422
RICH
38.1
0.35
--
--
10.5
46.5
43.0
GRADATION CURVES
Project: Hollymead Town Center
16009.02
Contract:
110.0
109.0
108.0
107.0
106.0
-105.0
a
z104.0
w
0
ry
'103.0
102.0
101.0
100.0
99.0
98.0
11
13 15 17 19 21
WATER CONTENT, %
Sample Description: SILTY SAND (sM), fine to coarse grained Assumed Specific Gravity:
sand, contains rock fragments and mica, Max. Dry Density (pcf):
red -brown (Visual)
Opt. Moisture (%):
Sample Source: S-1, 0.0 ft
Test Methods: ASTM D698 Method B
Liquid Limit (LL): --
Plasticity Index (PI): --
% Retained #4 Sieve: 6.9
% Passing # 200 Sieve: 43.1
Comments:
23
2.60
107.5
17.3
Date: 2-03-17 Reviewed By: DS
MOISTURE DENSITY RELATIONSHIP
Project: Hollymead Town Center
16009.02
Contract:
Testing Lab: RICH
116.0
115.0
114.0
113.0
112.0
108.0
107.0
106.0
105.0
104.0
9
\
\
\
\
\
11 13 15 17 19
WATER CONTENT, %
Sample Description: SILTY SAND (sM), fine to coarse grained Assumed Specific Gravity:
sand, contains rock fragments and mica, Max. Dry Density (pcf):
red -brown (Visual)
Opt. Moisture (%):
Sample Source: S-2, 0.0 ft
Test Methods: ASTM D698 Method C
Liquid Limit (LL): --
Plasticity Index (PI): --
% Retained #4 Sieve: 8.5
% Passing # 200 Sieve: 36.8
Comments:
21
2.63
112.9
15.3
Date: 2-03-17 Reviewed By: DS
MOISTURE DENSITY RELATIONSHIP
Project: Hollymead Town Center
16009.02
Contract:
Testing Lab: RICH
112.0
111.0
110.0
109.0
108.0
-107.0
a
z106.0
w
0
ry
'105.0
104.0
103.0
102.0
101.0
100.0
11
13 15 17 19 21
WATER CONTENT, %
Sample Description: SILTY SAND (sM), fine to coarse grained Assumed Specific Gravity:
sand, contains rock fragments and mica, Max. Dry Density (pcf):
red -brown (Visual)
Opt. Moisture (%):
Sample Source: S-3, 0.0 ft
Test Methods: ASTM D698 Method C
Liquid Limit (LL): --
Plasticity Index (PI): --
% Retained #4 Sieve: 10.5
% Passing # 200 Sieve: 43.0
Comments:
23
2.61
108.0
16.8
Date: 2-03-17 Reviewed By: DS
MOISTURE DENSITY RELATIONSHIP
Project: Hollymead Town Center
16009.02
Contract:
Testing Lab: RICH
underhilI ENGINEERING
geotechnical I geothermal I geoconstruction
March 7, 2018
Mr. Katurah Roell
Town Properties, LLC
325 Barracks Hill
Charlottesville, VA 22901
Subject: Construction Engineering and Testing Services in Pavement
Areas, Hollymead Towncenter Block C4, Albemarle County,
Virginia (Underhill Engineering Project No. 16009.02)
Dear Mr. Roell:
Underhill Engineering, LLC (Underhill) is pleased to present this letter, summarizing
Underhill's services for the above -referenced project. These services are provided in
accordance with Underhill's Services Agreement with you dated March 1, 2016.
Underhill's services for the project included construction observation and testing in the new
pavement areas. These services included observation and testing of utility backfill including fill
placed in areas of pavements, observations of subgrades, observations of aggregate, and
California Bearing Ratio (CBR) testing. We provided our services from April 11, 2016, through
March 15, 2017. Soil laboratory test results consisting of soil classification, Standard Proctor
tests, and CBR test results were provided to you in our report dated March 15, 2017.
Note that the majority of the site pavement subgrades are in areas of cut consisting of
generally firm SILTY SAND (SM) residuum containing rock fragments. The earthwork
observation and testing of compacted structural fill placed in the pavement areas as provided
by Underhill indicated that the compacted structural fill observed and tested to be compacted
to at least 95 percent of the maximum dry density in accordance with ASTM D698, Standard
Proctor, and in general accordance with the project documents prepared by Dominion
Engineering last revised December 17, 2013. Also, CBR testing indicated the three samples of
on -site soils to exhibit laboratory CBR values of 12.9, 18.5, and 18.5; each exceeding the
design CBR value of 10.
Based on our observations and testing, including the high CBR test results obtained, we
consider the project's constructed pavement section to be suitable for the design traffic.
T: 434.531.2565
327 W. Main Street, Suite 2, Charlottesville, VA 22903
underhillengineering.com
Underhill has endeavored to complete the services identified herein in a manner consistent
with that level of care and skill ordinarily exercised by members of the profession currently
practicing in the same locality and under similar conditions as this project. No other
representation, express or implied, is included or intended, and no warranty or guarantee is
included or intended in this report.
Thank you for the opportunity to provide our services. If you have any questions or require
additional information, please do not hesitate to contact me.
Sincerely,
UNDERHILL ENGINEERING, LLC
/'�-* ,�—
O. Christopher Webster, PE
Principal
l40#N
4V' LTH Ow
� L�
0 0. CIT ISTOPIOR
U W f?85'lFdt
Lic. No. 019910
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Project 16009.02 / March 7, 2018 2 Underhill Engineering, LLC