S06 GeoTech Report 550 21 105.pdf

Report of Geotechnical Engineering Investigation Revised 04.20.2021 Construct Parking Lot/Street Lighting GH Area 1900 East Main Street Danville, Illinois Patriot Project No.: 21-0099-01G GDI Project No.: 19.5002.12 VA Project No.: 550-21-105

PPrreeppaarreedd FFoorr::

Mr. Kyle Cyr

Guidon Design 1221 North Pennsylvania Street Indianapolis, Indiana 46202

PPrreeppaarreedd BByy::

Patriot Engineering and Environmental, Inc.

6150 East 75th Street Indianapolis, Indiana 46250

April 20, 2021

April 20, 2021

Mr. Kyle Cyr Guidon Design 1221 North Pennsylvania Street Indianapolis, Indiana 46202

Re: Report of Geotechnical Engineering Investigation Revised 04.20.2021

Construct Parking Lot/Street Lighting GH Area 1900 East Main Street Danville, Illinois Patriot Project No.: 21-0099-01G

Dear Kyle:

Attached is the revised report of our geotechnical engineering investigation for the above referenced project. This investigation was completed in general accordance with our Proposal No. P20-1835-01G dated December 22, 2020.

This report includes graphic logs of three (3) soil borings drilled at the proposed project site. Also included in the report are the results of laboratory tests performed on samples obtained from the site, and geotechnical recommendations pertinent to the site development, pavement design, and construction.

We appreciate the opportunity to perform this geotechnical engineering investigation and are looking forward to working with you during the construction phase of the project. If you have any questions regarding this report or if we may be of any additional assistance regarding any geotechnical aspect of the project, please do not hesitate to contact our office.

Respectfully submitted, PPaattrriioott EEnnggiinneeeerriinngg aanndd EEnnvviirroonnmmeennttaall,, IInncc..

IIaann GGrraaffee,, EE..II.. WWiilllliiaamm DD.. DDuubbooiiss,, PP..EE..

Geotechnical Engineer Senior Principal Engineer

Danville VA Parking Lot Guidon Design Danville, Illinois Patriot Project No.: 21-0099-01G

Patriot Engineering and Environmental, Inc. Page ii

TTAABBLLEE OOFF CCOONNTTEENNTTSS

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1.1 General

1.2 Purpose and Scope

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3.1 Site Conditions

3.2 General Subsurface Conditions

3.3 Field Infiltration Testing Results

3.4 Groundwater Conditions

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4.1 Basis

4.2 Pavements

4.3 Storm-Water Management Basin

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5.1 Site Preparation

5.2 Structural Fill and Fill Placement Control

5.3 Chemical Modification Considerations

5.4 Groundwater Considerations

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6.1 Field Work

6.2 Laboratory Testing

AAPPPPEENNDDIICCEESS

Appendix A: Site Vicinity Map (Figure No. 1) Boring Location Map (Figure No. 2) Boring Logs Boring Log Key Unified Soil Classification System (USCS) Appendix B: Pavement Design Evaluation & Design Sections

Appendix C: General Qualifications Standard Clause for Unanticipated Subsurface Conditions

Patriot Engineering and Environmental, Inc. Page 1

RREEPPOORRTT OOFF GGEEOOTTEECCHHNNIICCAALL EENNGGIINNEEEERRIINNGG IINNVVEESSTTIIGGAATTIIOONN Construct Parking Lot/Street Lighting GH Area

1900 East Main Street Danville, Illinois

Patriot Project No.: 21-0099-01G

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11..11 GGeenneerraall

VA Illiana Health Care System, in conjunction with Guidon Design, is planning the construction of a visitor parking lot to be located at 1900 East Main Street in Danville, Illinois. The results of our geotechnical engineering investigation for the project are presented in this report.

11..22 PPuurrppoossee aanndd SSccooppee The purpose of this investigation is to determine the general near surface and subsurface conditions within the project area and to develop the geotechnical engineering recommendations necessary for the design and construction of the proposed parking lot.

This was achieved by drilling soil borings, and by conducting laboratory tests on samples taken from the borings. This report contains the results of our findings, geotechnical engineering interpretation of these results with respect to the available project information, and recommendations to aid in the design and construction of the proposed parking lot.

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The proposed project is located at 1900 East Main Street in Danville, Illinois. The project consists of a new visitor parking lot. Additionally, we understand that a storm-water management area will be associated with the project. Based on visual observations of the existing site, it is assumed that any grade raise fill to complete the construction of building pads, finished pavement subgrades, etc., will not exceed 2 feet above the existing ground surface.

Patriot Engineering and Environmental, Inc. Page 2

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33..11 SSiittee CCoonnddiittiioonnss The project site is presently a flat open field on the VA property. The field is covered in grass with some trees located in the field. The surrounding area is generally an area of residential and commercial development. The topography in the area proposed for construction is generally flat.

33..22 GGeenneerraall SSuubbssuurrffaaccee CCoonnddiittiioonnss

Our interpretation of the subsurface conditions is based upon three (3) soil borings drilled at the approximate locations shown on the Boring Location Map (Figure No. 2) in Appendix “A”. All depths discussed below refer to depths below the existing ground surface. Based on the results of the soil borings completed at the site, the following subsurface profile is presented. A description of each general soil unit has been identified and is described below:

Topsoil – Topsoil, a surficial layer of material that is a blend of silts, sands, and clays, with varying amounts of organic matter, was encountered at the ground surface all of the boring locations. The topsoil layer was about 6 to 12 inches thick in the borings.

Silty and/or Sandy Clay (CL and CL-ML) - The topsoil layer is generally underlain by medium stiff to hard silty and/or sandy clay. The silty and/or sandy clay layers typically extends to depths of 10 feet below the existing ground surface. The natural moisture content of this material ranging from 9 to 24 percent (%). The silty and/or sandy clay layers have hand penetrometer values of 1.0 to greater than 4.5 tons per square foot (tsf).

Standard Penetration Test N-values (blow counts) in this material varied from 5 to 27 blows per foot (bpf). A layer of very soft to soft silty clay was encountered in Boring B-3 from 0 to 6.5 feet below the existing ground surface. This soft clay has a natural moisture content ranging from 26 to 27 percent (%). The Standard Penetration Test N- Values in this material were 1 and 3 bpf.

Clayey Sand (SC) – Within the silty and/or sandy clay layers, very loose clayey sand was encountered from 3.5 to 6.5 feet below existing grade at Boring B-2. The Standard Penetration Test N-value in this clayey sand was 2 bpf.

As previously mentioned, unsuitable very soft to soft clays and very loose sands were encountered in two (2) of the three (3) borings, at depths up to 6 feet below the

Patriot Engineering and Environmental, Inc. Page 3 existing ground surface. The following table presents the extent of the unsuitable soils encountered in the borings:

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Boring Number Soil Classification

Approximate Depth of Unsuitable Soils

(feet)(1)

B-2 Very Loose Clayey Sand (SC) 3.5 to 6.5

B-3 Very Soft to Soft Silty Clay (CL) 0 to 6.5

(1) Represents depth below existing ground surface.

The soil conditions described above are general, and some variations in the descriptions should be expected; for more specific information, please refer to the boring logs presented in Appendix “A”. It should be noted that the dashed stratification lines shown on the soil boring logs indicate approximate transitions between soil types. In-situ stratification changes could occur gradually or at different depths.

33..33 FFiieelldd IInnffiillttrraattiioonn TTeessttiinngg Per the Client’s request, we performed one (1) percolation test at the site to get a general idea of the infiltration rates for the storm-water management basin. The test was conducted in Boring B-2 at a depth of 2.5 feet below the existing ground surface. The soil encountered at the percolation test level was silty clay. The result of the field infiltration tests was 0.5 inches per hour.

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The term groundwater pertains to any water that percolates through the soil found on site.

This includes any overland flow that permeates through a given depth of soil, perched water, and water that occurs below the “water table”, a zone that remains saturated and water-bearing year-round.

Groundwater was observed during drilling in one (1) of the three (3) soil borings performed at the site at depths of 3.5 feet below the existing ground surface. Groundwater was not observed in the remaining borings during drilling. The borings were dry at the cave-in depths shown on the boring logs after drilling was completed.

It should be recognized that fluctuations in the groundwater level should be expected over time due to variations in rainfall and other environmental or physical factors. The

Patriot Engineering and Environmental, Inc. Page 4 true static groundwater level can only be determined through observations made in cased holes over a long period of time, the installation of which was beyond the scope of this investigation.

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Our recommendations are based on data presented in this report, which include soil borings, laboratory testing, and our experience with similar projects. Subsurface variations that may not be indicated by a dispersive exploratory boring program can exist on any site.

If such variations or unexpected conditions are encountered during construction, or if the project information is incorrect or changed, we should be informed immediately since the validity of our recommendations may be affected.

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Very soft to soft clays and very loose clayey sands were encountered at two (2) of the three (3) Borings (B-2 and B-3). Per the request of the client, we are presenting two (2) options for remediation of the site.

Option 1: Low Risk All soft clays, very loose sands, and other unsuitable materials must be removed and replaced with well-compacted structural fill. Aggressive dewatering may be required during excavation. The design life of this option is 15 years.

Option 2: High Risk An alternative option the owner may consider is to excavate down 2.5 feet, install geogrid, and backfill over the geogrid with a minimum of 1 foot of well-compacted crushed stone. This option, however, will not last as long as the previous remediation option, significantly shortening the design life of the pavement. An estimate of the design life for the pavement if this option is used is less than 5 years. For more details, including design life, concerning this option, contact a geogrid vender.

Depending on the weather conditions at the time of construction, scarifying and drying and/or chemical modification (Refer to Section 5.3 “Chemical Modification Considerations”) may be necessary to manage moisture contents in the clays in

Patriot Engineering and Environmental, Inc. Page 5 order to achieve the necessary subgrade soil support prior to the placement of pavement sections or any grade raise fill.

If construction is performed during a wet or cold period, the contractor will need to exercise care during the grading and fill placement activities in order to achieve the necessary subgrade soil support for the pavement section (Refer to Section 5.0 “Construction Considerations”). The base soil for the pavement section will need to be firm and dry. The subgrade should be sloped properly in order to provide good base drainage. To minimize the effects of groundwater or surface water conditions, the base section for the pavement system should be sufficiently high above adjacent ditches and properly graded to provide pavement surface and pavement base drainage.

As requested, Patriot is providing minimum design recommendations for rigid (concrete), and flexible (asphalt) light duty pavement sections. These design recommendations have been evaluated and based on estimated design criteria (i.e. 15 year design life, equivalent single axle loading (ESAL) of 78,905 for rigid (concrete) pavement sections and 79,844 for flexible (asphalt) pavement sections), along with our evaluation of the subsurface conditions.

Our recommended minimum pavement design sections provided below are based on a soil support evaluation performed in accordance with generally accepted procedures set forth by the American Association of State Highway and Transportation Officials (AASHTO) “Guide for Design of Pavement Structures, 1993”. It should be recognized that because actual traffic loading conditions determined from a traffic study were not available for the referenced facility, all traffic loading conditions considered and utilized for design purposes were estimated based on our past experience with similar projects and the following design assumptions:

• Design Life of 15 years

• 18-kips Equivalent Single Axle Loading (ESAL) estimated design value:

o Rigid (400 car and 4 small truck passes per day) Pavement = 78,905 o Flexible (400 car and 4 small truck passes per day) Pavement = 79,844

• Initial Serviceability:

o Flexible Pavement = 4.2 o Rigid Pavement = 4.5

• Terminal Serviceability of 2.0 (for both flexible and rigid pavement)

• Reliability of 80 percent (%) (for both flexible and rigid pavement)

Patriot Engineering and Environmental, Inc. Page 6

• Standard Deviation o Flexible Pavement = 0.45 o Rigid Pavement = 0.35

• Estimated California Bearing Ratio (CBR) of 3

• The crushed stone base course will not contain more than 10 percent (%) fines and will be compacted to at least 100 percent (%) of the maximum Standard Proctor dry density.

• Asphalt will be placed and compacted in accordance with IDOT standard specifications.

• Good to Excellent Drainage Condition – Assumes water in subgrade is removed within 1 day. Please note, the shallow subgrade soils encountered at the site generally consist of clays with Relatively low permeability’s; which means the soils have relatively poor drainage characteristics. Therefore, we recommend installing longitudinal subsurface drains throughout the length of the proposed pavement areas. Additionally, we recommend the installation of series of finger drains within the proposed pavement areas; which if appropriate and feasible could be connected to storm-sewer inlets. In addition to providing good drainage, the installation of underdrains underlying pavement sections founded over low permeability soils will generally aid in improving long-term performance of the pavement sections, as well as helping lower maintenance costs.

Based on the above design parameters, provided below are the calculated minimum pavement design thicknesses for rigid (concrete) pavement loading and flexible (asphalt) pavement for the provided loading. Refer to Appendix “B” “Pavement Design Evaluation & Design Sections” for detailed design calculations.

Table 2: Rigid Light Duty Pavement Design (Minimum Thicknesses)

Traffic Loading Conditions(1)

Concrete (Inches)(2)

Aggregate Base Course

(Inches)(3)

Modulus of Subgrade Reactions

(psi)

Design Life

Option 1 (Years)(1)

78,905 ESAL’s 5.0 6 100 15

(1) Estimated ESAL based on estimated number of truck passes per day

(2) Minimum of 4,000 pounds per square inch (psi) concrete strength with suitable reinforcement

(3) Illinois Department of Transportation (IDOT) CA-6, containing no more than 10 percent (%) fines.

Patriot Engineering and Environmental, Inc. Page 7

Table 3: Flexible Light Duty Pavement Design (Minimum Thicknesses)

Traffic Loading Conditions(1)

Asphalt Surface Course HMA 9.5 mm (Inches)(2)

Asphalt Base Course HMA

19 mm (Inches)(2)

Aggregate Sub-Base (Inches)(3)

Design Life Option 1 (Years)(1)

79,844 ESAL’s 1.5 3.5 6 15

(1) Estimated ESAL based on estimated number of truck passes per day

(2) Illinois Department of Transportation (IDOT) Specified Hot Mix Asphalt (HMA)

(3) Illinois Department of Transportation (IDOT) CA-6, containing no more than 10 percent (%) fines.

44..33 SSttoorrmm--WWaatteerr MMaannaaggeemmeenntt BBaassiinn

A storm-water management basin will either be located near the proposed parking lot or beneath the proposed parking lot. The soils encountered in the boring generally consisted of silty or sandy clays, however, a layer of clayey sand was encountered in Boring B-2 from 3.5 to 6 feet below the existing ground surface. The clays are considered relatively favorable for a retention basin, due to the estimated moderate permeability characteristics of the clays. However, the sand layers generally encountered underlying the clays would not be favorable for retention of storm-water, as the sand layers are estimated to have relatively high permeability characteristics. In addition, based on our experience, pockets and layers of sands are anticipated within the clay layer. Therefore, if a retention capacity is required for the detention pond, the pond will require the installation of a clay liner, and/or a synthetic liner. However, if percolation of water into the underlying soil is allowed and maintaining a long-term pond level is not a concern, a liner may not be required.

The soils encountered in our borings should be readily excavated using conventional earthwork equipment. Additionally, depending on the invert elevation of the proposed detention basin, sand layers and seams could be encountered which are expected to be free-flowing and will tend to readily cave and/or slough into excavations; therefore, over-excavation, benching and/or shoring should be expected in order to maintain the side slopes of the excavations.

Depending on seasonal conditions and the invert elevation of the proposed detention basin, localized and sporadic groundwater infiltration should be expected to be encountered in the detention basin excavation (Refer to Section 5.4 “Groundwater Considerations”). Furthermore, it should also be noted that there may be the potential for encountering heaving of sand layers near the groundwater elevations during construction.

Patriot Engineering and Environmental, Inc. Page 8

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55..11 SSiittee PPrreeppaarraattiioonn All areas that will support pavements or newly placed structural fill must be properly prepared. All loose surficial soil or “topsoil” and other unsuitable materials must be removed. Unsuitable materials include frozen soil, relatively soft material, relatively wet soils, deleterious material, or soils that exhibit a high organic content.

Approximately six (6) to twelve (12) inches of loose surficial topsoil was encountered in the borings. The topsoil was measured at discrete locations as shown on the Boring Location Map (Figure No. 2) in Appendix “A”. The topsoil thickness measured at the boring locations may or may not be representative of the overall average topsoil thickness at the site. Therefore, it is possible that the actual stripping depth could significantly vary from this data. The data presented should be viewed only as a guide to the minimum stripping depth that will be required to remove organic material at the surface. Additional field exploration by Patriot would be required to provide an accurate estimate of the stripping depth. This limited data indicates that a minimum stripping depth will be required to remove the organic material at the surface, followed by the potential for additional stripping and/or scarification and recompaction as may be required to achieve suitable subgrade support. Additionally, if saturated conditions exist with the surface soils, light tracked equipment could be required to avoid pushing organics deeper into the suitable subgrade soils. A Patriot representative should verify the stripping depth at the time grading operations occur.

Prior to construction of pavements or the placement of new structural fill, the exposed subgrade must be evaluated by a Patriot representative, which will include proofrolling of the subgrade. Proofrolling should consist of repeated passes of a loaded, pneumatic-tired vehicle such as a tandem-axle dump-truck or scraper. The proofrolling operations should be observed by a Patriot representative, and the proofrolling vehicle should be loaded as directed by Patriot. Any area found to rut, pump, or deflect excessively should be compacted in-place or, if necessary, undercut and replaced with structural fill, compacted as specified in Section 5.3 “Structural Fill and Fill Placement Control”.

Care must be exercised during grading and fill placement operations. The combination of heavy construction equipment traffic and excess surface moisture can cause

Patriot Engineering and Environmental, Inc. Page 9 pumping and deterioration of the near surface soils. The severity of this potential problem depends to a great extent on the weather conditions prevailing during construction. The contractor must exercise discretion when selecting equipment sizes and also make a concerted effort to control construction traffic and surface water while the subgrade soils are exposed. We recommend that heavy construction equipment (i.e.

dump trucks, scrapers, etc.) be rerouted away from the building and pavement areas. If such problems do arise, the operations in the affected area should be halted and the Patriot representative contacted to evaluate the condition.

55..22 SSttrruuccttuurraall FFiillll aanndd FFiillll PPllaacceemmeenntt CCoonnttrrooll Structural fill, defined as any fill which will support structural loads, should be clean and free of organic material, debris, deleterious materials, and frozen soils. Samples of the proposed fill materials should be tested prior to initiating the earthwork and backfilling operations to determine the classification, the natural and optimum moisture contents and maximum dry density and overall suitability as a structural fill. Structural fill should have a liquid limit less than 40 and a plasticity index less than 20.

Structural fill supporting, around and over utilities should be compacted to at least 95 percent (%) of its maximum Standard Proctor dry density (ASTM D-698) for utilities underlying structural areas (i.e. buildings, pavements, sidewalks, etc.). However, the minimum compaction requirement can be reduced for backfill around and over the utilities to 90 percent (%) of the maximum Standard Proctor dry density where utilities underlie greenbelt areas (i.e. grassy lawns, landscaping, etc.). It is recommended that a clean well-grade granular material be utilized as the bedding material, as well as the backfill material around and over the utility lines.

In cut areas, where pavement sections are planned, the upper 10 inches of subgrade should be scarified and compacted to a dry density of at least 100 percent (%) of the Standard Proctor maximum dry density (ASTM D-698). Any grade-raise fill placed within 1 foot of the base of the pavement section should also be compacted to at least 100 percent (%) of the Standard Proctor maximum dry density. This can be reduced to 95 percent (%) for structural fill placed more than 1 foot below the base of the pavement section.

To achieve the recommended compaction of the structural fill, we suggest that the fill be placed and compacted in layers not exceeding 8 inches in loose thickness (the loose lift thickness should be reduced to 6 inches when utilizing small hand compactors) and within

Patriot Engineering and Environmental, Inc. Page 10 the range of 2 percentage (%) points below or above the optimum moisture content value.

All fill placement should be monitored by a Patriot representative. Each lift should be tested for proper compaction at a frequency of at least one (1) test every 2,500 square feet (ft2) per lift for the building areas, at least one (1) test every 10,000 square feet (ft2) per lift for the parking and roadway areas, and at a frequency of at least one (1) test for every 50 lineal feet of utility installation.

55..33 CChheemmiiccaall MMooddiiffiiccaattiioonn CCoonnssiiddeerraattiioonnss The addition of lime or lime kiln dust (LKD) to clay soils of moderate to high plasticity generally results in the reduction of the plasticity properties of the soil, reduction in moisture holding capacity, swell reduction, and increased soil strength. Prior to the application of the lime or lime kiln dust (LKD), a number of representative samples of soils should be obtained from the final graded subgrade soils to determine the lime or lime kiln dust (LKD) reactivity and percentage (%) of lime or lime kiln dust (LKD) needed for modification of the soils (usually 5 to 8 percent (%)). A specialty contractor experienced in lime modification should apply and determine the rate at which hydrated lime or lime kiln dust (LKD) is mixed into the existing soils. Mixing depths of 12 to 18 inches is typical. A Patriot representative should monitor the mixing and compaction processes.

It should be noted that in areas where chemical modification of the natural subgrade soil is completed prior to the placement of grade raise fill and the grade raise fill is less than 18 inches in thickness, we recommend that any cohesive grade raise fill be modified similar to the natural subgrade. It has been our experience that untreated cohesive structural fill, in less than 18 inches in thickness, placed on top of chemically modified soil may become unstable over time due to excessive moisture accumulation. The underlying chemically modified soil may act as a barrier to natural water seepage into the soil profile, thereby trapping the water within the structural fill to the point of saturation.

55..44 GGrroouunnddwwaatteerr CCoonnssiiddeerraattiioonnss

Groundwater was observed during our field activities at depths of about 3.5 feet below the existing ground surface; which is expected to be below the anticipated pavement excavation depths, though the groundwater observations could potentially be within trench excavation depths for subsurface utilities. Therefore, groundwater infiltration should be expected into the subsurface utility excavations, and depending on seasonal conditions, localized and sporadic groundwater infiltration may occur into the pavement excavations on this site.

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Groundwater inflow into shallow excavations above the groundwater table is expected to be adequately controlled by conventional methods such as gravity drainage and/or pumping from sumps. More significant inflow can be expected in deeper excavations below the groundwater table requiring more aggressive dewatering techniques, such as well or wellpoint systems. For groundwater to have minimal effects on the construction, pavement excavations should be constructed and poured in the same day, if possible.

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66..11 FFiieelldd WWoorrkk A total of three (3) soil borings were drilled, sampled, and tested at the project site on February 2, 2021 at the approximate locations shown on the Boring Location Map (Figure No. 2) in Appendix “A”. The depths that the soil borings were advanced to are shown on the Boring Logs in Appendix “A”. All depths are given as feet below the existing ground surface.

The borings were advanced using 3¼ inch inside diameter hollow-stem augers. Samples were recovered in the undisturbed material below the bottom of the augers using the standard drive sample technique in accordance with ASTM D 1586-74. A 2 inch outside diameter by 13/8 inch inside diameter split-spoon sampler was driven a total of 18 inches with the number of blows of a 140-pound hammer falling 30 inches recorded for each 6 inches of penetration. The sum of blows for the final 12 inches of penetration is the Standard Penetration Test result commonly referred to as the N-value (or blow-count).

Split-spoon samples were recovered at 2.5 feet intervals, beginning at a depth of 1 foot below the existing surface grade, extending to a depth of 10 feet, and at 5 feet intervals thereafter to the termination of the boring.

Water levels were monitored at each borehole location during drilling and upon completion of the boring. The boreholes were backfilled with auger cuttings prior to demobilization for safety considerations.

Upon completion of the boring program, of the samples retrieved during drilling were returned to Patriot’s soil testing laboratory where they were visually examined and classified. A laboratory-generated log of each boring was prepared based upon the driller’s field log, laboratory test results, and our visual examination. Test boring logs and a

Patriot Engineering and Environmental, Inc. Page 12 description of the classification system are included in Appendix “A” in this report.

Indicated on each log are the primary strata encountered, the depth of each stratum change, the depth of each sample, the Standard Penetration Test results, groundwater conditions, and selected laboratory test data. The laboratory logs were prepared for each boring giving the appropriate sample data and the textural description and classification.

66..22 LLaabboorraattoorryy TTeessttiinngg

Representative samples recovered in the borings were selected for testing in the laboratory to evaluate their physical properties and engineering characteristics. Laboratory analysis included natural moisture content determinations (ASTM D 2216) and an estimate of the cohesive soil strength was determined utilizing a hand penetrometer (qp). The results of laboratory tests are summarized in Section 3.2 “General Subsurface Conditions”.

Soil descriptions on the boring logs are in accordance with the Unified Soil Classification System (USCS).

AAPPPPEENNDDIIXX AA

SITE VICINITY MAP (FIGURE NO. 1)

BORING LOCATION MAP (FIGURE NO. 2)

BORING LOGS

BORING LOG KEY

UNIFIED SOIL CLASSIFICATION SYSTEM

(USCS)

21-0099-01_geo

Danville VA Parking Lot Design 1900 E. Main Street Danville, Illinois

J. DuMond

February 19, 2021Date: DWG:

21-0099-01

Project:

Project Number: Approved: I. Grafe Drawn By:

Figure 1

Site Vicinity Map

APPROX. SCALE IN FEET

1500'750'0

N

Patriot Engineering & Environmental, Inc.

Site Location

Image Source:

USGS Danville NE & SE Topos 2019

B-1

B-2

B-3 Blue Star Highway

Date:

Project:

Project Number:

Figure 2

APPROX. SCALE IN FEET

100500

Soil Boring Location Map

N

Patriot Engineering & Environmental, Inc.

NOTES:

1. Boring locations were staked by PATRIOT.

All locations are shown as approximate.

2. All locations were determined in the field with references to existing landmarks.

3. Image Source: Google Earth

4. Scale as shown.

LEGEND

PATRIOT Soil Boring

B-1 Soil Boring ID

21-0099-01_geo

Danville VA Parking Lot Design 1900 E. Main Street Danville, Illinois

J. DuMond

February 19, 2021 DWG:

21-0099-01 Approved: I. Grafe

Drawn By:

-2

6-

C

:\U se rs \ig ra fe

\P at rio t E ng in ee rin g\ G

E O

D oc um en ts

\M te ch \2 m te ch \0

9-

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\b 1.

bo r

Danville VA Parking Lot Design 1900 East Main Street

Danville, Illinois

LOG OF BORING B-1

(Page 1 of 1)

Client Name : Guidon Design Inc.

Project Number : 21-0099-01G

Logged By : J. Rogers

Start Date : 02/02/2021

Drilling Method : HSA

Driller : C. Dolan

Sampling : Splitspoon

Depth (Feet)

W at er L ev el

U S

C S

CL

CL

G R

A P

H

IC

DESCRIPTION

Water Levels

During Drilling - Dry

After Completion - Dry

After 24 Hours - N/A

TOPSOIL (6")

Brown, moist, medium stiff, SILTY CLAY with trace sand

Brown and gray, slightly moist, stiff to hard, SANDY CLAY

Boring terminated at 10 feet.

S am pl es

Rec

SPT

Results

2/3/4

1/4/8

5/11/16

10/7/14 qp tsf

>4.5

>4.5 w

REMARKS

Boring caved to 3 feet upon auger removal.

Groundwater was not encountered during drilling, nor upon completion.

6-

C

:\U se rs \ig ra fe

\P at rio t E ng in ee rin g\ G

E O

D oc um en ts

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Danville VA Parking Lot Design 1900 East Main Street

Danville, Illinois

LOG OF BORING B-2

(Page 1 of 1)

Client Name : Guidon Design Inc.

Project Number : 21-0099-01G

Logged By : J. Rogers

Start Date : 02/02/2021

Drilling Method : HSA

Driller : C. Dolan

Sampling : Splitspoon

Depth (Feet)

W at er L ev el

U S

C S

CL

SC

CL

G R

A P

H

IC

DESCRIPTION

Water Levels

During Drilling - 3.5 feet

After Completion - Dry

After 24 Hours - N/A

TOPSOIL (12")

Brown, moist, medium stiff to stiff, SILTY CLAY with trace sand

Dark brown and brown, saturated, very loose, CLAYEY SAND with trace gravel

Brown and gray, slightly moist, stiff, SANDY CLAY with trace gravel

Boring terminated at 10 feet.

S am pl es

Rec

SPT

Results

2/3/2

1/1/1

WOH/3/6

2/4/6 qp tsf

1.25 w

REMARKS

Boring caved to 2 feet upon auger removal.

WOH - Weight of Hammer

6-

C

:\U se rs \ig ra fe

\P at rio t E ng in ee rin g\ G

E O

D oc um en ts

\M te ch \2 m te ch \0

9-

G

\b 3.

bo r

Danville VA Parking Lot Design 1900 East Main Street

Danville, Illinois

LOG OF BORING B-3

(Page 1 of 1)

Client Name : Guidon Design Inc.

Project Number : 21-0099-01G

Logged By : J. Rogers

Start Date : 02/02/2021

Drilling Method : HSA

Driller : C. Dolan

Sampling : Splitspoon

Depth (Feet)

W at er L ev el

U S

C S

CL

CL

CL

CL

G R

A P

H

IC

DESCRIPTION

Water Levels

During Drilling - Dry

After Completion - Dry

After 24 Hours - N/A

TOPSOIL (12")

Brown and gray, very moist, very soft, SILTY CLAY with trace sand

Brown and gray, very moist, soft, SILTY CLAY with trace sand

Brown and gray, slightly moist, medium stiff, SANDY CLAY with trace gravel

Brown, slightly moist, medium stiff to stiff, SANDY CLAY with trace gravel

Boring terminated at 10 feet.

S am pl es

Rec

SPT

Results

WOH/WOH/1

1/1/2

1/2/5

3/3/5 qp tsf

1.25 w

REMARKS

Boring caved to 4 feet upon auger removal.

Groundwater was not encountered during drilling, nor upon completion.

WOH - Weight of Hammer

BORING LOG KEY

UNIFIED SOIL CLASSIFICATION SYSTEM

FIELD CLASSIFICATION SYSTEM

FOR SOIL EXPLORATION

NON COHESIVE SOILS

(Silt, Sand, Gravel and Combinations)

Density Grain Size Terminology

Very Loose -4 blows/ft. or less Soil Fraction Particle Size US Standard Sieve Size Loose -5 to 10 blows/ft.

Medium Dense -11 to 30 blows/ft. Boulders Larger than 12” Larger than 12” Dense -31 to 50 blows/ft. Cobbles 3” to12” 3” to 12” Very Dense -51 blows/ft. or more Gravel: Coarse ¾” to 3” ¾” to 3”

Small 4.76mm to ¾” #4 to ¾” Sand: Coarse 2.00mm to 4.76mm #10 to #4 Medium 0.42mm to 2.00mm #40 to #10 Fine 0.074mm to 0.42mm #200 to #40 Silt 0.005mm to 0.074 mm Smaller than #200 Clay Smaller than 0.005mm Smaller than #200

RELATIVE PROPORTIONS FOR SOILS

Descriptive Term Percent Trace 1 - 10 Little 11 - 20 Some 21 - 35 And 36 - 50

COHESIVE SOILS

(Clay, Silt and Combinations)

Unconfined Compressive Field Identification (Approx.)

Consistency Strength (tons/sq. ft.) SPT Blows/ft.

Very Soft Less than 0.25 0 - 2 Soft 0.25 – < 0.5 3 - 4 Medium Stiff 0.5 - < 1.0 5 - 8 Stiff 1.0 - < 2.0 9 -15 Very Stiff 2.0 - < 4.0 16 - 30 Hard Over 4.0 > 30

Classification on logs are made by visual inspection.

Standard Penetration Test - Driving a 2.0” O.D., 1

3/8 ” I.D., sampler a distance of 1.0 foot into undisturbed soil with a 140 pound hammer free falling a distance of 30.0 inches. It is customary for Patriot to drive the spoon 6.0 inches to seat into undisturbed soil, then perform the test. The number of hammer blows for seating the spoon and making the tests are recorded for each 6.0 inches of penetration on the drill log (Example - 6/8/9). The standard penetration test results can be obtained by adding the last two figures (i.e. 8 + 9 = 17 blows/ft.).

Strata Changes - In the column “Soil Descriptions” on the drill log the horizontal lines represent strata changes.

A solid line (

) represents an actually observed change, a dashed line (- - - - - -) represents an estimated change.

Groundwater observations were made at the times indicated. Porosity of soil strata, weather conditions, site topography, etc., may cause changes in the water levels indicated on the logs.

Groundwater symbols: ▼-observed groundwater elevation, encountered during drilling; ∇-observed groundwater elevation upon completion of boring.

Unified Soil Classification System

Major Divisions Group Symbol Typical Names Classification Criteria for Coarse-Grained Soils

C o a rs e -g ra in e d s o ils

(m re t h a n h a lf o f m a te ri a l is l a rg e r th a n N o

G ra v e ls re t h a n h a lf o f c o a rs fr a c ti o n i s l a rg e r th a n N o s ie v e s iz e

C le a n g ra v ls

(l it tl e o r n fi e s

GW

Well-graded gravels, gravel-sand mixtures, little or no fines

CU > 4

1 < CC < 3

D60

CU =

D10

D

CC=

D10 D60

GP

Poorly graded gravels, gravel-sand mixtures, little or no fines Not meeting all gradation requirements for

GW (CU < 4 or 1 > CC > 3) G ra v e ls w h

(a p p re c ia b le m o u n t o f fi n e s

GM

d u Silty gravels, gravel-sand-silt mixtures

Atterberg limits below A line or PI< 4

Above A line with

4 < PI < 7

are borderline cases requiring use of dual symbols GC Clayey gravels, gravel-sand-clay mixtures Atterberg limits above

A line or PI > 7

S a n d re t h a n h a lf o f c o a rs fr c ti o n i s s m a lle r th a n N o ie v e s iz e

C le a n s a n d tl e o r e s

SW

Well-graded sands, gravelly sands, little or no fines

CU > 6

1 < CC < 3

D60

CU =

D10

(D30)

CC=

D10 D60

SP

Poorly graded sands, gravelly sands, little or no fines Not meeting all gradation requirements for

SW (CU < 6 or 1 > Cc > 3)

S a n d s w

(a p p re c ia b le m o u n t o f fi n e s

SM

d u Silty sands, sand-silt mixtures

Atterberg limits below A line or PI < 4

Limits plotting in hatched zone with 4 < PI < 7 are borderline cases requiring use of dual symbols SC Clayey sands, sand-clay mixtures Atterberg limits above

A line with PI > 7

F in e -g ra in e d s re t h a n h a lf o f m a te ri a l is s m a lle r th a n N o

S ilt a n d c la y iq u id l im it

ML

Inorganic silts and very fine sands, rock flour, silty or clayey fine sands, or clayey silts with slight plasticity

1. Determine percentages of sand and gravel from grain size curve.

2. Depending on percentages of fines (fraction smaller than 200 sieve size), coarse-grained soils are classified as follows:

Less than 5% - GW, GP, SW, SP More than 12% - GM, GC, SM, SC 5-12% - Borderline cases requiring dual symbols

CL

Inorganic clays of low to medium plasticity, gravelly clays, sandy clays, silty clays, lean clays

OL

Organic silts and organic silty clays of low plasticity

S ilt s a n d c la y iq u id l im it

) MH

Inorganic silts, micaceous or diatomaceous fine sandy or silty soils, elastic silts

CH Inorganic clays or high plasticity, fat clays

OH

Organic clays of medium to high plasticity, organic silts

H ig ly rg a ic

PT Peat and other highly organic soils

Plasticity Chart

0 10 20 30 40 50 60 70 80 90 100

Liquid Limit WL

P la s ti c it y I n d e x P

I

ML & OL

CL-ML

U-LINE

CH

CL

A-LINE

U-LINE: PI = 0.9(WL-8)

A-LINE: PI = 0.73(WL-20)

OH & MH

AAPPENDIX B

PAVEMENT DESIGN EVALUATION & DESIGN SECTIONS

WinPAS Pavement Thickness Design According to

1993 AASHTO Guide for Design of Pavements Structures American Concrete Pavement Association

Rigid Design Inputs

Danville VA Parking Lot Design 1900 East Main Street Danville, Illinois

Patriot Engineering

Rigid Pavement Design/Evaluation

Concrete Thickness Total Rigid ESALs Reliability Overall Standard Deviation Flexural Strength Modulus of Elasticity

5.00 78,905

80.00 0.35

4,400,000 inches psi psi percent

Load Transfer Coefficient Modulus of Subgrade Reaction Drainage Coefficient Initial Serviceability Terminal Serviceability

3.20

1.00 4.50 2.00 psi/in.

Modulus of Subgrade Reaction (k-value) Determination

Resilient Modulus of the Subgrade Unadjusted Modulus of Subgrade Reaction

Depth to Rigid Foundation Loss of Support Value (0,1,2,3)

4,500.0

0.00 0.0 psi feet

Modulus of Subgrade Reaction

Project Name:

Route:

Location:

Owner/Agency:

Design Engineer:

psi/in1

100 psi/in.

Wednesday, February 24, 2021 10:55:11AM Engineer:

WinPAS Pavement Thickness Design According to

1993 AASHTO Guide for Design of Pavements Structures American Concrete Pavement Association

Flexible Design Inputs

Project Name:

Route:

Location:

Owner/Agency:

Design Engineer:

Flexible Pavement Design/Evaluation

Structural Number Total Flexible ESALs Reliability Overall Standard Deviation percent Terminal Serviceability Initial Serviceability Subgrade Resilient Modulus

Layer Pavement Design/Evaluation

Layer Material

Layer Coefficient

Drainage Coefficient

Layer Thickness

Layer

SN

Danville VA Parking Lot Design 1900 East Main Street Danville, Illinois

Patriot Engineering

2.58 79,844 80.00 0.45

4,500.00 4.20 2.50 psi

Asphalt Cement Concrete 0.39 1.00 1.50 0.58 Asphalt Cement Concrete 0.36 1.00 3.50 1.26 Crushed Stone Base 0.14 1.00 6.00 0.84

SN 2.68

Wednesday, February 24, 2021 10:55:12AM Engineer:

AAPPPPEENNDDIIXX CC

GENERAL QUALIFICATIONS

STANDARD CLAUSE FOR UNANTICIPATED

SUBSURFACE CONDITIONS

GENERAL QUALIFICATIONS

of Patriot Engineering’s Geotechnical Engineering Investigation

This report has been prepared at the request of our client for his use on this project.

Our professional services have been performed, findings obtained, and recommendations prepared in accordance with generally accepted geotechnical engineering principles and practices. This warranty is in lieu of all other warranties either expressed or implied.

The scope of our services did not include any environmental assessment or investigation for the presence or absence of wetlands, hazardous or toxic materials in the soil, groundwater, or surface water within or beyond the site studied. Any statements in this report or on the test borings logs regarding vegetation types, odors or staining of soils, or other unusual conditions observed are strictly for the information of our client and the owner.

This report may not contain sufficient information for purposes of other parties or other uses. This company is not responsible for the independent conclusions, opinions or recommendations made by others based on the field and laboratory data presented in this report. Should there be any significant differences in structural arrangement, loading or location of the structure, our analysis should be reviewed.

The recommendations provided herein were developed from the information obtained in the test borings, which depict subsurface conditions only at specific locations. The analysis, conclusions, and recommendations contained in our report are based on site conditions as they existed at the time of our exploration. Subsurface conditions at other locations may differ from those occurring at the specific drill sites. The nature and extent of variations between borings may not become evident until the time of construction. If, after performing on-site observations during construction and noting the characteristics of any variation, substantially different subsurface conditions from those encountered during our explorations are observed or appear to be present beneath excavations, we must be advised promptly so that we can review these conditions and reconsider our recommendations where necessary.

If there is a substantial lapse of time between the submission of our report and the start of work at the site, or if conditions have changed due to natural causes or construction operations at or adjacent to the site, we urge that our report be reviewed to determine the applicability of the conclusions and recommendations considering the changed conditions and time lapse.

We urge that Patriot be retained to review those portions of the plans and specifications that pertain to earthwork and foundations to determine whether they are consistent with our recommendations. In addition, we are available to observe construction, particularly the compaction of structural backfill and preparation of the foundations, and such other field observations as may be necessary.

In order to fairly consider changed or unexpected conditions that might arise during construction, we recommend the following verbiage (Standard Clause for Unanticipated Subsurface Conditions) be included in the project contract.

STANDARD CLAUSE FOR UNANTICIPATED SUBSURFACE CONDITIONS

"The owner has had a subsurface exploration performed by a soils consultant, the results of which are contained in the consultant's report. The consultant's report presents his conclusions on the subsurface conditions based on his interpretation of the data obtained in the exploration. The contractor acknowledges that he has reviewed the consultant's report and any addenda thereto, and that his bid for earthwork operations is based on the subsurface conditions as described in that report. It is recognized that a subsurface exploration may not disclose all conditions as they actually exist and further, conditions may change, particularly groundwater conditions, between the time of a subsurface exploration and the time of earthwork operations. In recognition of these facts, this clause is entered in the contract to provide a means of equitable additional compensation for the contractor if adverse unanticipated conditions are encountered and to provide a means of rebate to the owner if the conditions are more favorable than anticipated.

At any time during construction operations that the contractor encounters conditions that are different than those anticipated by the soils consultant's report, he shall immediately (within 24 hours) bring this fact to the owner's attention. If the owner's representative on the construction site observes subsurface conditions which are different than those anticipated by the consultant's report, he shall immediately (within

24 hours) bring this fact to the contractor's attention. Once a fact of unanticipated conditions has been brought to the attention of either the owner or the contractor, and the consultant has concurred, immediate negotiations will be undertaken between the owner and the contractor to arrive at a change in contract price for additional work or reduction in work because of the unanticipated conditions. The contract agrees that the following unit prices would apply for additional or reduced work under the contract. For changed conditions for which unit prices are not provided, the additional work shall be paid for on a time and materials basis."

Another example of a changed conditions clause can be found in paper No. 4035 by

Robert F. Borg, published in ASCE Construction Division Journal, No. CO2, September

1964, page 37.