Geotechnical Report.pdf

SOILS AND FOUNDATIONS REPORT

REPORT NO. 03-21

PROJECT: BLUE RIDGE PARKWAY SLOPE FAILURES REPAIR

AT MP 119.7 & MP 127.9

VA ERFO NPS BLRI 2020-1(2)

BLUE RIDGE PARKWAY, ROANOKE COUNTY, VIRGINIA

US DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

22001 LOUDON COUNTY PARKWAY

BUILDING E-2, SUITE 200

ASHBURN, VA 20147

JULY 2021

TABLE OF CONTENTS

1. INTRODUCTION

1.1. General

1.2. Background

2. GEOLOGIC SETTING

3. SUBSURFACE EXPLORATION PROGRAM

3.1. Subsurface Exploration

3.2. Field Testing and Sampling

3.3. Laboratory Testing

4. SUBSURFACE CONDITIONS

4.1. General Stratification

4.1.1. MP 127.9 (Borings BH20-01 and BH20-02)

4.1.2. MP 119.7

5. ANALYSIS AND RECOMMENDATIONS

5.1. Geotechnical Evaluation

5.2. Design Alternatives

5.3. Recommendations

5.4. Analyses

6. REFERENCES

7. DISCLAIMER/LIMITATIONS CLAUSE

APPENDICES

Appendix A – Figures Appendix B – Borings Location Map Appendix C – Borings Logs Appendix D – Laboratory Testing Results Appendix E – Slope Stability Analyses Appendix F – Selected Photographs

Note: Design changes subsequent to publication of this report and prior to the project’s advertisement will be documented by a memo attached after the title page.

PROJECT: BLUE RIDGE SLOPE FAILURE

AT MP 119.7 AND MP 127.9

BLUE RIDGE PARKWAY, ROANOKE COUNTY, VIRGINIA

PAGE 3 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

SOILS AND FOUNDATIONS REPORT

REPORT NO. 03-21

PROJECT: BLUE RIDGE PARKWAY SLOPE FAILURES REPAIR

AT MP 119.7 & MP 127.9

BLUE RIDGE PARKWAY, ROANOKE COUNTY, VIRGINIA

1. INTRODUCTION

1.1. General

This report presents the results of our subsurface exploration, laboratory testing, geotechnical analysis, and recommendations for the slope failures at MP 119.7 and MP 127.9 in the Blue Ridge Parkway. The failure at MP 119.7 is a cut slide and is located southwest of Garden City, while the failure at MP 129.7 is a fill slide and is located south of Poages Mill, in Roanoke County, Virgina. The sites location is shown in Figure 1, Appendix A.

1.2. Background

A storm event in May 2020 caused the subject slope failures and the Parkway was closed from MP 115.2 to MP 129.

The slide at MP 119.7 is approximately 100 feet long and 30 feet at it highest section. Several head scarps up to 5 feet deep were observed during our site reconnaissance of June 2nd, 2020. The landslide debris blocked the road ditch.

The slope failure at MP 127.9 is approximately 80 feet long with up to 15 feet high exposed head scarps.

The pavement measured 10 to 12 inches thick showing several layers of pavement overlays, indicating previous repairs. Saturation of the slope face was noted during our site reconnaissance.

2. GEOLOGIC SETTING

The bedrock geologic maps of the Southern Appalachian Mountains (2008) & Geologic map of the Garden City quadrangle, Virginia (2011), indicate that the parent rocks are characterized by metamorphic and sedimentary rocks, respectively. The metamorphic rocks at MP 127.9 are from the early to middle Proterozoic age that are part of the Piedmont and Blue Ridge provinces. The formation includes Gneiss rock. The bedrock at the project sites appears to be Porphyroblastic granite gneiss. The major sedimentary rock at MP 119.7 is shady dolomite. This formation is from the Cambrian age and consists of dolostone with dark bands of shale and limestone. Site geology maps are provided in Figures 2 & 2A, Appendix A.

BLUE RIDGE PARKWAY, ROANOKE COUNTY, VIRGINIA

PAGE 4 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

3. SUBSURFACE EXPLORATION PROGRAM

3.1. Subsurface Exploration

A subsurface exploration program was conducted at the MP 127.9 site on January 7 through January 9, 2021 by EFLHD subsurface exploration team. The program consisted of drilling two (2) soil borings (BH20-01 and BH20-02) on either side of the slide. The borings were advanced to their termination depths with a CME 750 ATV-mounted rotary drill rig. The boring locations were selected by EFLHD geotechnical engineer based on the location of the observed damage, presence of underground utilities, and accessibility of the drilling rig. All boreholes were backfilled with auger cuttings after completion. Boreholes were laid out by EFLHD field personnel by measuring distances from mapped landmarks and using a hand-held GPS units. Boring elevations were determined from the topographic plans. Borings BH20-01 and BH20-02 extended to depths of 35.3 ft. and 18.6 ft. below existing site grades, respectively. Approximate borings location is shown on the Borings Location Plan in Appendix B.

3.2. Field Testing and Sampling

The borings were advanced to the termination depths using 3-¾ –in. (ID) hollow stem augers (HSA). Soil samples were obtained using a 2¼- in (OD) split-barrel (split-spoon) sampler driven during Standard Penetration Tests (SPT) in general accordance with AASHTO T206. Soil samples were typically recovered at 5.0 ft intervals by driving the split-spoon sampler a distance of 24 inches into the undisturbed soil under the impact of a 140-lb. automatic hammer free-falling 30 inches. The total number of blows recorded for the middle twelve inches of the 24-inch sample range is designated as the “Standard Penetration Resistance” or N-value. Spoon refusal, if encountered, is defined as greater than 50 blows per 6-inches of penetration of the split-spoon sampler.

The number of blows required to advance the sampler through each 6-inch interval was recorded on the field boring logs. Upon completion of the SPT, the sampler was removed from the borehole and sample recovery measurements were made and recorded for each sampling event. A field description by color, texture, and moisture was made for each recovered sample. Representative portions of split-spoon samples were preserved in glass jars for laboratory testing. The SPT N-values for each sampling event were recorded on the boring logs.

The results of field tests and measurements were recorded on the driller’s logs and appropriate data sheets in the field. These data sheets and logs contain information concerning the boring methods; samples attempted and recovered; indications of the presence of various material such as gravel, pebbles, organic matter, etc.; and observations of groundwater. They also contain interpretations by the exploration team of the subsurface conditions based on the performance of the equipment and cuttings brought to the surface by the drilling tools. Therefore, the field data represents both factual and interpretative information.

BLUE RIDGE PARKWAY, ROANOKE COUNTY, VIRGINIA

PAGE 5 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

Soil samples collected in the field were delivered to EFLHD Materials Testing facility in Sevierville, TN for laboratory testing and storage. The sampling sequence and associated samples for the boring is presented in Appendix C.

The boring logs in Appendix C represent a compilation of field data and description of the soil samples by a geotechnical engineer. These records occasionally do not include all data recorded on the driller’s logs and field data sheets, but include all information considered relevant to the analysis and preparation of this report.

Groundwater level measurements, if present, were conducted at the times and under the conditions stated in the boring logs. It must be noted that fluctuations in groundwater level may occur due to seasonal variations, rainfall, temperature, and other factors not evident at the time measurements were taken.

3.3. Laboratory Testing

A laboratory-testing program was conducted on representative soil samples recovered during the subsurface exploration to determine the soil engineering properties required for the analyses. The laboratory tests included, natural moisture content (AASHTO T-265), Atterberg limits (AASHTO T-89/90), particle size analysis (AASHTO T-88), and soil classification (AASHTO M-145). The results of the laboratory testing program are presented in Appendix D and summarized in Table 1.

Table 1 – Summary of Soil Laboratory Testing Results

NP: Non-plastic USCS: Unified Soil Classification System

Boring

No.

Sample Depth

(ft)

AASHTO

Classification

USCS

Classification

MC

PL

LL

PI

BH20-01 10-12 A-2-4(0) Silty sand 17.2 26 36 10

BH20-01 20-22 A-2-4(0) Silty sand 22.8 NP NV NP

BH20-01 25-27 A-4(0) Silty sand 26.6 NP NV NP

BH20-01 30-32 A-2-4(0) Silty sand 24.8 NP 20 NP

BH20-02 10-12 A-1-b Silty sand with gravel

7.4 NP NV NP

BH20-02 15-17 A-2-4(0) Silty sand with gravel

14.6 NP 20 NP

BLUE RIDGE PARKWAY, ROANOKE COUNTY, VIRGINIA

PAGE 6 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

4. SUBSURFACE CONDITIONS

4.1. General Stratification

A brief description of the soil and rock conditions encountered during the subsurface exploration is presented below. The stratification lines designating the interfaces between soil types on the boring logs represent approximate boundaries. The transition between materials may be gradual. It should be noted that one or more of the units may be absent at specific locations. Subsurface conditions may vary between the boring locations.

4.1.1. MP 127.9 (Borings BH20-01 and BH20-02)

Asphalt pavement and base course A 1.5± ft thick layer of asphalt concrete and base course were encountered in the borings.

Fill Materials Underneath the asphalt and base course layers, fill materials were encountered in the borings and extended to depths of 18.6 ft and 30.0 ft below existing site grades in borings BH20-02 and BH20-01, respectively.

The fill consisted primarily of silty sand and sandy silt soils. SPT N-values ranged from 3 to 27 blows per foot (bpf), indicating loose to medium dense relative densities and very stiff consistency.

Natural Deposits Underneath the fill materials, natural deposits were encountered and extended to the borings auger refusal depths in Boring BH20-01. This layer consisted primarily of very loose silty sands.

Auger Refusal Auger refusal was encountered at depths of 35.3 ft and 18.6 ft below existing site grades in borings BH20- 1 and BH20-02, respectively. No rock coring was performed in this study.

Groundwater No groundwater was encountered in the borings during our drilling operations. Fluctuations in the groundwater conditions due to seasonal weather changes and other factors should be anticipated.

The boring logs are included in Appendix C.

4.1.2. MP 119.7

No subsurface exploration was performed at this site. Per the USDA Web Soil Survey, the surficial materials are described as Edgemont channery sandy loam. USDA described the engineering properties of these upper soils as follows:

• 0-6 in. – Channery sandy loam, SC & SM, A-2 & A-4, LL of 21-37, PI of 2-13

• 6-38 in. - Channery sandy clay loam to clay loam, CL, A-6, LL of 29-45, PI of 12-25

• 38-62 in. - Channery sandy loam, CL & ML, A-6 & A-4, LL of 16-40, PI of 2-21

BLUE RIDGE PARKWAY, ROANOKE COUNTY, VIRGINIA

PAGE 7 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

The geologic map of the area indicates that the site is underlain by Shady Dolomite (dark-gray, fine-grained limestone and minor interbedded black shale) at depth.

5. ANALYSIS AND RECOMMENDATIONS

5.1. Geotechnical Evaluation

Landslides occur as a result of unbalanced pressures along the sloping ground. The presence of water acts as a trigger mechanism by increasing the driving forces and/or reducing the shear strength of the in-situ materials. To mitigate slope stability problems, various approaches can be used. One approach is to reduce the driving forces and increasing shear strength. The shear strength can be increased by lowering the groundwater table which can be attained by improving the surface and subsurface drainage systems.

Another approach is increasing the resisting forces. Increasing the resisting forces can be achived by buttressing the slope, adding a retaining structure, or by reinforcing the slope.

5.2. Design Alternatives

Various alternatives were considered given their feasibility and effectiveness, site subsurface conditions, constructability, cost, and our experience with similar projects. A brief discussion of each alternative is presented below.

Alternative No. 1 – Gabion Baskets Wall

This alternative consists of re-establishing the roads and stabilize the slope by constructing a gabion wall.

These walls consist of wiremesh baskets that are filled with stone and placed on top of each other to form a self draining retaining wall. Gabion walls are essentially gravity type walls and would require considerable thickness in order to provide adequate stability. They can sustain considerable deformation and differential settlements.

Alternative No. 2 – Reinforced Soil Slope (RSS)

Reinforced soil slopes are constructed using common construction materials, and conventional equipment and techniques, providing an economical and durable structure. These type of walls are cost effective, self-draining, and can tolerate larger differential settlements compared to other repair alternatives and they can be more esthetically pleasant. The reinforcing can be achieved by placement of howizontal gyosynthetic or metal elements.

Alternative No. 3 – Mechanically Stabilized Earth (MSE)

This alternative consists of re-establishing the roadway and stabilize the slope by constructiing a retaining wall with geosynthetic reinforced soil. MSE walls typically have precast panel facing. Alternatively, these structures can be constructed with welded wire or gabion facing that provides the opportunity for vegetation to grow and mimic the surrounding landscape.

BLUE RIDGE PARKWAY, ROANOKE COUNTY, VIRGINIA

PAGE 8 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

Alternative No. 4 –Soil Nail Reinforcing

Soil nails are reinforcing elements that are drilled and grouted in the ground to support unstable slopes.

5.3. Recommendations

Based on our observations during the site reconnaissance, the results of our subsurface exploration program, geotechnical analyses, and a discussion with our partner, it was concluded that soil nail reinforcing would be used at MP 119.7 (cut slide) and Reinforced Soil Slope (RSS) at MP 127.9 (fill slide).

We recommend that the reinforced soil slope includes a subsurface drainage system composed of granular backfill and a perforated 6” diameter pipe. The drainage system should be surrounded by a filter fabric to prevent the migration of fines. The perforated 6” diameter pipe will drain subsurface water into a 6” diameter non-perforated outlet pipe located in the lowest point behind the wall. To keep wildlife out of the retaining wall drainage system a 1/4” mesh should be installed to cover the 6” diameter non-perforated pipe outlet.

5.4. Analyses

The slope stability anlayses of the proposed earth retaining systems were conducted using limit equilibrium methodology, in general accordance with the design concepts and procedures presented in FHWA Publication FHWA-GEC 007, “Geotechnical Engineer Circular No. 7 - Soil Nail Walls Reference Manual,” (2015), FHWA Publication FHWA-GEC 11 “Geotechnical Engineer Circular No. 11 – Design of Mechanically Stabilized Earth Walls and Reinforced Soil Slopes” (2009), and following “AASHTO LRFD Bridge Design Specifications, 9th Ed.” (2020) design requirements. A uniform distributed live surcharge load was applied along the roads to account for traffic loading following AASHTO-LRFD, 2020, Section

3.11.6.4 requirements. A summary of the soil engineering parameters assumed in the external, internal, and global stability analyses of both sites are presented in Table 2.

Table 2 - Summary of assumed engineering properties for analysis.

Material Type Unit Weight (pcf) Cohesion (psf) Internal Friction Angle ϕ (°)

Existing Fill – Silty Sand (SM) 115 0.0 30

Colluvium - Sand (SC/SM) or

Clay/Silt (CL/ML) 120 0.0 32

Rock – Siltstone 135 0.0 38

Rolled Erosion Control 125 Infinite

Granular Backfill 115 0.0 34

The assumed bond strength of soil nail for the retained soil at MP 119.7 is shown in Table 3.

BLUE RIDGE PARKWAY, ROANOKE COUNTY, VIRGINIA

PAGE 9 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

Table 3 - Assumed bond strength of soil nail for retained soil - MP 119.7 Material Type qBond (psi)

Existing Fill and Residual Soil (SM or ML) 12.0

The selected load factors and combinations are presented in Table 4. The factors follow (AASHTO-LRFD, 2020). The resistance factors and Factors of Safety requirements for the analysis of reinforced soil slopes are presented in Table 5 and Table 6.

Table 4 – Retaining wall load factors and combinations – MP 119.7 and MP 127.9.

Load Combination EH EV ES LS EQ

Strength I (Max) 1.50 1.35 1.50 1.75 -

Strength I (Min) 0.90 1.00 0.75 1.75 -

Service I 1.00 1.00 1.00 1.00 -

Extreme Event I 1.00 1.00 1.00 1.00 or 0.50 1.00

Table 5 - Soil Nail System resistance factors – MP 119.7.

Analysis Resistance Factor

Anchor Pullout Resistance Φ: 0.65

Anchor Tensile Resistance Φ: 0.75

Overall/Global Φ: 0.65 (FS:1.5)

Overall/Global Extreme Event I Φ: 0.9 (FS:1.1)

Table 6 – Reinforced Soil Slope resistance factors – MP 127.9.

Analysis Resistance Factor

Sliding Resistance Φ: 1.00 (FS:1.5)

Overall/Global Φ: 0.75 (FS:1.3)

Overall/Global Extreme Event I Φ: 0.9 (FS:1.1)

The global/overall stability analysis computations were performed using the computer program Slide 2 by Rocscience, Inc. Copies of the computer output are included in Appendix E.

According to AASHTO 11.5.4.2, a seismic design shall not be considered mandatory for walls located in Seismic Zones 1 through 3, or for walls at Sites where the site adjusted peak ground acceleration is less than or equal to 0.4g, unless one or more of the following is true:

• Liquefaction induced lateral spreading or slope failure, or seismically induced slope failure, due to the presence of sensitive clays that lose strength during the seismic shaking, may impact the stability of the wall for the design earthquake.

BLUE RIDGE PARKWAY, ROANOKE COUNTY, VIRGINIA

PAGE 10 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

• The wall supports another structure that is required, based on the applicable design code or specification for the supporting structure, to be designed for seismic loading and poor seismic performance of the wall could impact the seismic performance of that structure.

In addition, according to C11.5.4.2, paragraph 7, a seismic analysis should be considered mandatory if the wall is located in seismic zone 2 or higher, and if either of the following is greater than 30 feet:

• The exposed wall height plus the average depth over the width of the wall of any soil surcharge present.

• For tiered walls, the sum of the exposed height of all the tiers plus the average soil surcharge depth.

Based on the above listed criteria, we concluded that the retaining structure systems selected do not require an external or internal seismic evaluation due to an adjusted PGA less than 0.4g, and the retaining structures are in Seismic Zone 1 to 3. However, an Extreme Event I global stability analysis is required for all sites.

For this analysis, an assumed allowable lateral deformation was established based on the flexible nature of the types of structure. See the evaluation calculations in Appendix E for details.

A summary of the retaining structure parameters are presented in Tables 7 and 8 below.

Table 7 - Soil Nail System details – MP 119.7.

Approximate

Retained Height (ft.)

Soil Nail Tensile

Capacity (lb.)

Soil Nail Length

(ft.)

Soil Nail downward inclination

(from horizontal) (degrees)

Soil Nail vertical and horizontal spacing (ft.)

Bearing Plate load capacity

(lb.)

24 25,000 20 15 10 25,000

Table 8 – Reinforced Soil Slope – MP 127.9.

Approximate Reinforced Height (ft.)

Slope face inclination

Geogrid Spec.

Nominal Long- Term

Strength (lb/ft.)

Minimum geogrid length

(ft.)

Maximum geogrid vertical spacing

(ft.)

42 1V:1H Type IV 2,500 35 1.5

The proposed soil nail and reinforced slope systems satisfied the minimum static and Extreme Event I (seismic) global stability requirements with the following factors of safety.

BLUE RIDGE PARKWAY, ROANOKE COUNTY, VIRGINIA

PAGE 11 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

Table 9 – Global/Overall Stability Calculated Factors of Safety.

Site

Calculated Factor of Safety

Static Seismic

MP 119.7 2.017 1.860

MP 127.9 1.315 1.222

Details of the global stability analyses are included in Appendix E.

BLUE RIDGE PARKWAY, ROANOKE COUNTY, VIRGINIA

PAGE 12 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

6. REFERENCES

AASHTO-LRFD. (2020). AASHTO LRFD Bridge Design Specification (9th ed.). Washington, D.C.:

American Association of State Highway and Transportation Officials.

FHWA (2009) FHWA-NHI-10-024 & -025, “Geotechnical Engineer Circular No. 11 – Design of Mechanically Stabilized Earth Walls and Reinforced Soil Slopes”. Washington DC

FHWA. (2009). Geotechnical Engineer Circular - Ground Anchors and Anchored Systems. Washington

DC: FHWA.

FHWA. (2014). Standard Specifications For Construction of Roads and Bridges on Federal Highway Projects (FP-14). US Department of Transportation. Washington D.C.: US Department of Transportation.

FHWA. (2015). Strength Characterization of Open-Graded Aggregates for Structural Backfills - FHWA- HRT-15-034. McLean: FHWA.

BLUE RIDGE PARKWAY, ROANOKE COUNTY, VIRGINIA

PAGE 13 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

7. DISCLAIMER/LIMITATIONS CLAUSE

The subsurface explorations and tests described in this report have been conducted in accordance with standard practices and procedures (except as specifically noted). The results of these exploration and tests represent conditions at the specific locations and dates indicated. Subsurface conditions between these locations may vary. The Geotechnical Analyses and Recommendations Sections of this report include interpretations and recommendations developed by the Government in the process of preparing the design.

These interpretations are not intended as a substitute for the personal investigation, independent interpretation, and judgment of the Contractor.

Prepared by:

Girmay Weldegiorgis, P.E.

Geotechnical Engineer

Reviewed by:

Mounir Abouzakhm, P.E.

Division Geotechnical Engineer

P ROJECT: KENDALL CAMPGROUND

RIVERBANK AND BOAT RAMP FIALURES REPAIR

RUSSELL COUNTY, KENTUCKY

PAGE 14 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

APPENDICES

Appendix A – Figures Appendix B – Borings Location Map Appendix C – Borings Logs Appendix D – Laboratory Testing Results Appendix E – Slope Stability Analyses Appendix F – Selected Photographs

DEPARTMENT OF TRANSPORTATION

APPENDIX A – FIGURES

Data to create map retrieved from ArcGIS Online

U.S. DEPARTMENT OF TRANSPORTATION

FEDERAL LANDS HIGHWAY DIVISION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VIRGNIA

FIGURE NO. 1

Site location

STATE PROJECT SHEET

NO.

TOTAL

SHEETS

VA VA ERFO NPS BLRI 2020-1(2) 1 1

Geology of the southern Appalachian Mountains Authors: Clark, S.H.B.

Retrieved on June 29, 2021: https://ngmdb.usgs.gov/Prodesc/proddesc_86253.htm Scale: 1:806,000, USGS (2008)

TOTAL

SHEETS

VA ERFO NPS BLRI

2020-1(2)

STATE

VA

SHEET

NO.

PROJECT

EASTERN FEDERAL LANDS HIGHWAY DIVISION

FIGURE 2

GEOLOGIC MAP

FEDERAL LANDS HIGHWAY DIVISION

U.S. DEPARTMENT OF TRANSPORTATION

ASHBURN, VIRGINIA

Geologic map of the Garden City quadrangle, Virginia Authors: Henika, W.S.

Retrieved on June 29, 2021: https://ngmdb.usgs.gov/Prodesc/proddesc_97480.htm Scale: 1:24,000, USGS (2011)

TOTAL

SHEETS

VA ERFO NPS BLRI

2020-1(2)

STATE

VA

SHEET

NO.

PROJECT

EASTERN FEDERAL LANDS HIGHWAY DIVISION

FIGURE 2A

GEOLOGIC MAP

FEDERAL LANDS HIGHWAY DIVISION

U.S. DEPARTMENT OF TRANSPORTATION

ASHBURN, VIRGINIA

APPENDIX B – BORINGS LOCATION MAP

APPENDIX C – BORING LOGS

10/04/2018

SOIL CLASSIFICATION CHART

Criteria for Assigning Group Symbols and Group Name Using Laboratory TestsA Group

Symbol Group NameB

COARSE-GRAINED

SOILS

More than 50% retained on No. 200 Sieve

GRAVELS

More than 50% of coarse fraction retained on No. 4 Sieve

Clean GRAVELS Less than 5% fines E

Cu ≥ 4 and 1 ≤ Cc ≤ 3C GW Well-graded GRAVEL D

Cu < 4 and/or 1 > Cc > 3 C GP Poorly-graded GRAVEL D

GRAVELS with fines More than 12% fines E

Fines classify as ML or MH GM Silty GRAVEL D,F Fines classify as CL or CH GC Clayey GRAVEL D,F

SANDS

Less than 50% retained on No. 4 Sieve

Clean SANDS Less than 5% fines I

Cu ≥ 6 and 1 ≤ Cc ≤ 3 C SW Well-graded SAND H

Cu < 6 and/or 1 > Cc > 3 C SP Poorly-graded SAND H

SANDS with fines More than 12% fines I

Fines classify as ML or MH SM Silty SAND F,H Fines classify as CL or CH SC Clayey SAND F,H

FINE-GRAINED

SOILS

50% or more passes the No. 200 Sieve

SILTS and CLAYS Liquid limit less than 50

Inorganic PI > 7 and plots on or above the “A” line J CL Lean CLAY K,L,M PI < 4 or plots below “A” line J ML SILT K,L,M

Organic Liquid limit – oven dried Liquid limit – not dried < 0.75 OL Organic CLAY K,L,M,N

Organic SILT K,L,M,O

SILTY and CLAYS Liquid limit 50 or more

Inorganic PI plots on or above “A” line CH Fat CLAY K,L,M PI plots below “A” line MH Elastic SILT K,L,M

Organic Liquid limit – oven dried Liquid limit – not dried < 0.75 OH Organic CLAY K,L,M,P

Organic SILT K,L,M,Q

HIGHLY ORGANIC

SOILS Primarily organic matter, dark in color, and organic odor PT PEAT A Based on material passing the 3-inch sieve.

B If field sample contains cobbles or boulders, add “with cobbles” or “boulders” or both, to group name.

C Cu = D60/D10 Cc = (D30)2 / (D10 x D60) D If soil contains ≥15% sand, add “with sand” to group name.

E Gravels with 5 to 12% fines require dual symbols:

GW-GM well-graded GRAVEL with silt GW-GC well-graded GRAVEL with clay GP-GM poorly-graded GRAVEL with silt GP-GC poorly-graded GRAVEL with clay

F If fines classify as CL-ML, use dual symbol GC-GM or SC-SM G If fines are organic, add “with organic fines” to group name.

H If soil contains ≥15% gravel, add “with gravel” to group name.

I Sand with 5 to 12% fines require dual symbols:

SW-SM well-graded SAND with silt SW-SC well-graded SAND with clay SP-SM poorly-graded SAND with silt SP-SC poorly-graded SAND with clay J If Atterberg limits plot in hatched area, soil is a CL-ML, silty

CLAY.

K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel”, whichever is predominant.

L If soil contains ≥ 30% plus No. 200, predominantly sand, add “sandy” to beginning of group name.

M If soil contains ≥ 30% plus No. 200, predominantly gravel, add “gravelly” to beginning of group name.

N PI ≥ 4 and plots on or above “A” line.

O PI < 4 or plots below “A” line.

P PI plots on or above “A” line.

Q PI plots below “A” line.

APPARENT DENSITY OF COARSE-

GRAINED SOIL

SPT N-value (blows per foot) Apparent Density

0 to 4 Very Loose

5 to 10 Loose

11 to 30 Medium Dense

31 to 50 Dense

> 50 Very Dense

CONSISTENCY OF

FINE-GRAINED SOIL

SPT N-value (blows per foot) Consistency

0 to 1 Very Soft

2 to 4 Soft

5 to 8 Firm

9 to 15 Stiff

16 to 30 Very Stiff

> 30 Hard

SOIL STRUCTURE TERMS

Stratified Alternating layers of varying material or color with layers > 1/4 inch (6 mm), note thickness and inclination.

Laminated(1) Alternating layers of varying material or color with layers < 1/4 inch (6 mm), note thickness and inclination.

Fissured(1) Breaks along definite planes of fracture with little resistance to fracturing.

Slickensided(1) Fracture planes appear polished or glossy, sometimes striated.

Blocky(1) Cohesive soil that can be broken down into smaller angular lumps which resists further breakdown.

Disrupted Soil structure is broken and mixed. Infers that material has moved substantially -landslide debris.

Homogeneous Same color and appearance throughout.

Lensed Inclusion of small pockets of different soil, such as small lenses of sand scattered through a mass of clay; < 1/4 inch (6 mm) note thickness.

(1) Do not use laminated, fissured, slickensided, or blocky for coarse-grained soils.

Descriptive Terminology for Boring Logs

Field descriptions of borings are based on the FLH Soil and Rock Description and Identification Guidelines that generally follow the Visual-Manual Procedure (ASTM D 2488). The soil classifications shown on the boring logs are based on laboratory tests (ASTM D 2487) when the two-letter group symbol follows the group name in parenthesis.

Standard Penetration Test (SPT): the SPT consists of driving a 2 in (50 mm) O.D. split barrel sampler a depth of 18 in (450 mm) or 24 in (600 mm) using a 140 lb (63.6 kg) hammer with a 30 in (750 mm) drop. The blow count is the number of blows recorded for each 6 inch (50 mm) increment.

The N-value is the total number of blows for the second and third increments. Note that the N-values shown on the boring logs do not include any corrections for non-standard sampler size, hammers, drill rods, etc.

ANGULARITY OF

COARSE-GRAINED SOILS

Angular

Sharp edges and relatively plane sides with unpolished surfaces

Subangular

Similar to angular description, but with rounded edges

Subrounded

Nearly plane sides, but will have well-rounded corners and edges.

Rounded

Smoothly curved sides and no edges

PARTICLE SIZE OF COARSE-GRAINED SOILS

Component Grain Size Limits

Boulders > 12” (> 300 mm)

Cobbles 3 – 12” (75 – 300 mm)

Coarse Gravel 3/4 - 3" (19 - 75 mm)

Fine Gravel #4 Sieve - 3/4" (4.75 - 19 mm)

Coarse Sand #10 - #4 Sieve (2.00 - 4.75 mm)

Medium Sand #40 - #10 Sieve (0.425 - 2.00 mm)

Fine Sand #200 - #40 Sieve (0.075 - 0.425 mm)

10/04/2018

GRAIN/CRYSTAL SIZE FOR ROCKS (MODIFIED AFTER WENTWORTH, 1972)

Grain Size Description Criteria Less than 0.003 inches (<0.075 mm)

Very fine grained Cannot be distinguished by unaided eye. Few to no mineral grains are visible with a hand lens.

0.003 to 0.02 inches (0.075 to 0.425 mm) Fine grained

Few grain/crystal boundaries are visible; grains can be distinguished with difficulty by the unaided eye but can be somewhat distinguished by hand lens.

0.02 to 0.08 inches (0.425 to 2 mm) Medium grained Most grain/crystal boundaries are visible; grains distinguishable by eye and with the aid of a hand lens.

0.08 to 0.2 inches

(2 to 4.75 mm) Coarse grained Grain/crystal boundaries are visible; grains distinguishable with the naked eye and hand lens.

Greater than 0.2 inches

(>4.75 mm)

Very coarse grained

Grain/crystal boundaries are Clearly visible; grains are distinguishable with the naked eye.

GRAIN SHAPE (FOR SEDIMENTARY ROCKS)

Description Characteristic

Angular Showing very little evidence of wear. Grain edges and corners are sharp. Secondary corners are numerous and sharp.

Subangular

Showing definite effects of wear. Grain edges and corners are slightly rounded off. Secondary corners are slightly less numerous and slightly less sharp than in angular grains.

Subrounded Showing considerable wear. Grain edges and corners are rounded to smooth curves. Secondary corners are reduced greatly in number and highly rounded.

Rounded Showing extreme wear. Grain edges and corners are smoothed off the broad curves. Secondary corner are few in number and rounded.

Well-rounded Completely worn. Grain edges or corners are not present. No secondary edges or corners are present. DEGREE OF WEATHERING

Term Description Grade

Fresh No visible sign of rock material weathering; slight discoloration on major discontinuity surface is possible. I

Slightly Weathered

Discoloration indicates weathering of rock material and discontinuity surfaces. All rock material may be discolored by weathering and the external surface may be somewhat weaker than in its fresh condition.

II

Moderately Weathered

Less than half the rock material is decomposed and/or disintegrated to a soil.

Fresh or discolored rock is present either as a discontinuous framework or as corestones. A minimum 2-inch (50 mm) diameter sample cannot be broken readily by hand across the rock fabric.

III

Highly Weathered

More than half of the rock is decomposed and/or disintegrated to soil. Fresh or discolored rock is present either as a discontinuous framework or as corestones.

A minimum 2-inch (50 mm) diameter sample can be broken readily by hand across the rock fabric.

IV

Completely Weathered

All rock material is decomposed and/or disintegrated to soil. The original mass structure is still largely intact. Material can be granulated by hand. If rock is considered to be completely weathered, use FLH Soil Description and Identification Guidelines to describe the residual soil material.

V

Residual Soil

All rock material is converted to soil. The mass structure and material fabric are destroyed but the apparent structure remains intact. There may be a large change in volume, but the soil has not been significantly transported. Material can be easily broken-down by hand. If rock is considered to be completely weathered, use FLH Soil Description and Identification Guidelines to describe the residual soil material.

VI

RELATIVE STRENGTH OF SOIL INFILLING (ISRM, 1978 & 1981)

Grade Description Field Identification Approximate

Uniaxial Compressive

Strength

S1 Very Soft Easily penetrated several inches by fist

<3.5 psi (<25 kPa)

S2 Soft Easily penetrated severl inches by thumb

3.5 - 7 psi (25 - 50 kPa)

S3 Firm

Can be penetrated several inches by thumb with moderate effort

7 - 14.5 psi (50 - 100 kPa)

S4 Stiff

Readily indented by thumb but penetrated only with great effort

14.5 - 36 psi (100 - 250 kPa)

S5 Very Stiff Readily indented by thumbnail

36 - 72.5 psi (250 - 500 kPa)

S6 Hard Indented with difficulty by thumbnail

>72 psi (>500 kPa)

RELATIVE STRENGTH OF INTACT ROCK SPECIMENS (ISRM, 1978 &1981)

Grade Description Field Indentificaiton Approximate Uniaxial Compressive Strength

R0 Extremely Weak Rock Specimen can be indented by thumbnail 35 - 150 psi

(250 - 1,000 kPa)

R1 Very Weak Rock

Specimen crumbles under sharp blow with point of geological hammer, and can be peeled with a pocket knife.

150 - 725 psi (1,000 - 5,000 kPa)

R2 Weak Rock Shallow cuts or scrapes can be made in a specimen with a pocket knife. A firm blow with a geological hammer point creates shallow indents.

725 - 3,500 psi (5,000 - 25,000 kPa)

R3 Medium Strong Rock

Specimen cannot be scraped or cut with a pocket knife.

Specimen can be fractured with a single firm blow with a geologic hammer point.

3,500 - 7,250 psi (25,000 - 50,000 kPa)

R4 Strong Rock Specimen requires more than one firm blow of the geologic hammer point to fracture.

7,250 - 14,500 psi (50,000 - 100,000 kPa)

R5 Very Strong Rock

Specimen requires many firm blows from the hammer end of the geologic hammer to fracture.

14,500 - 36,250 psi (100,000 - 250,000 kPa)

R6 Extremely Strong Rock

Specimen can only be chipped with firm blows from the hammer end of the geologic hammer.

>36,250 psi (>250,000 kPa)

JRC RANGES (ISRM, 1978 &1981)

DISCONTINUITY CONDITION (ISRM, 1978, 1981)

Condition Description

Excellent Condition

Very rough surfaces, no separation, hard discontinuity wall (>R2).

Good Condition

Slightly rough surfaces, separation less than ~0.04 inches (1 mm), hard discontinuity wall (>R2).

Fair Condition

Slightly rough surface, separation greater than ~0.04 inches (1 mm), soft discontinuity wall (<R3).

Poor Condition

Slickensided surfaces, or soft gouge less than ~0.2 inches (5 mm) thick, or open discontinuities between ~0.4 and 0.2 inches (1 to 5 mm).

Very Poor Condition

Soft gouge greater than ~0.2 inches (5 mm), or open discontinuities greater than ~0.2 inches (5 mm).

DISCONTINUITY SPACING (INCLUDES

JOINTS/FRACTURES, BEDDING, AND FAULTS

Description Spacing of Discontinuity Extremely Widely

Spaced >20 feet (>6 m)

Very Widely Spaced

~6 to 20 feet (2 to 6 m)

Widely Spaced ~2 to 6 feet (600 mm to 2 m)

Moderately Spaced

~8 inches to 2 feet (200 to 600 mm)

Closely Spaced ~2 to 8 inches (60 to 200 mm)

Very Closely Spaced

~3/4 to 2 inches (20 to 60 mm)

Extremely Closely Spaced

<3/4 inches (<20 mm)

𝑅𝑅𝑅𝑅𝑅𝑅 (%) =

𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿ℎ 𝑜𝑜𝑜𝑜 𝑆𝑆𝑜𝑜𝑆𝑆𝐿𝐿𝑆𝑆 𝐶𝐶𝑜𝑜𝐶𝐶𝐿𝐿 𝑖𝑖𝐿𝐿 𝑝𝑝𝑖𝑖𝐿𝐿𝑝𝑝𝐿𝐿𝑝𝑝 > 4 𝑖𝑖𝐿𝐿𝑝𝑝ℎ𝐿𝐿𝑝𝑝 (100 𝑚𝑚𝑚𝑚)

𝑇𝑇𝑜𝑜𝐿𝐿𝑇𝑇𝑇𝑇 𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿ℎ 𝑜𝑜𝑜𝑜 𝐶𝐶𝑜𝑜𝐶𝐶𝐿𝐿 𝑅𝑅𝑆𝑆𝐿𝐿

𝑥𝑥 100

𝐹𝐹𝐹𝐹 =

𝑁𝑁𝑆𝑆𝑚𝑚𝑁𝑁𝐿𝐿𝐶𝐶 𝑜𝑜𝑜𝑜 𝐿𝐿𝑇𝑇𝐿𝐿𝑆𝑆𝐶𝐶𝑇𝑇𝑇𝑇 𝑜𝑜𝐶𝐶𝑇𝑇𝑝𝑝𝐿𝐿𝑆𝑆𝐶𝐶𝐿𝐿𝑝𝑝

𝑇𝑇𝑜𝑜𝐿𝐿𝑇𝑇𝑇𝑇 𝑇𝑇𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿ℎ 𝑜𝑜𝑜𝑜 𝑝𝑝𝑜𝑜𝐶𝐶𝐿𝐿 𝐶𝐶𝐿𝐿𝑝𝑝𝑜𝑜𝑟𝑟𝐿𝐿𝐶𝐶𝐿𝐿𝑆𝑆 (𝑜𝑜𝐿𝐿𝐿𝐿𝐿𝐿)

𝐶𝐶𝑅𝑅 (%) = �

𝑇𝑇𝑜𝑜𝐿𝐿𝑇𝑇𝑇𝑇 𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿ℎ 𝑜𝑜𝑜𝑜 𝐶𝐶𝑜𝑜𝐶𝐶𝐿𝐿 𝑅𝑅𝐿𝐿𝑝𝑝𝑜𝑜𝑟𝑟𝐿𝐿𝐶𝐶𝐿𝐿𝑆𝑆

𝑇𝑇𝑜𝑜𝐿𝐿𝑇𝑇𝑇𝑇 𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿ℎ 𝑜𝑜𝑜𝑜 𝐶𝐶𝑜𝑜𝐶𝐶𝐿𝐿 𝑅𝑅𝑆𝑆𝐿𝐿 𝑅𝑅𝐶𝐶𝑖𝑖𝑇𝑇𝑇𝑇𝐿𝐿𝑆𝑆

� ∗ 100

1.1

0.7

1.2

1.0

1.3

1.6

ASPHALT PAVEMENT

BASE COURSE

Silty SAND with gravel (SM), loose, brown, moist.

A-2-4(0). Fill.

Silty SAND (SM), very loose to loose, brown, moist, trace of gravel. A-2-4(0). Fill.

Silty SAND (SM), loose, brown, moist. A-4(0). Fill.

3-6-4-4

5-5-5-7

3-4-3-3

0-1-2-2

1-3-6-6

2-4-6-8

J-1

J-2

J-3

J-4

J-5

J-6

0.9 1.4

11.0

22.0

30.0

Project Location:

Encountered at:

After

Caved at:

Hammer Drop:

Rock Core (RQD in %)

(Blows / ft)

1589.0 ft

Undisturbed (UD)

1/8/21

Project Name:

MATERIAL DESCRIPTION

Boring No.:

Groundwater Depth:

Sample Types:

BORING LOG

1/9/21 Doug Hutchins Jason FarleyOperator:

T yp e

Weather:

SAMPLE

Plastic Limit

No groundwater was encountered during our drilling operation.

The borehole was backfilled with auger cuttings upon completion.

hrs

Remarks:

Auger Cuttings

G ra ph ic

L og

VA ERFO NPS BLRI 2020-1(2)

Density, Color, Plasticity, Size, Proportions, Moisture

Surface Elevation:

Boring Location:

La ye r

D ep th ft)

Boring Began:

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

Liquid Limit

SPT

U. S. DEPARTMENT OF TRANSPORTATION

At Completion:

Completed:

S P

T B lo w s pe r in

D ep th S ca le ft

N o.

BLRI, MP 119.7 and MP 127.9, Roanoke County, VA

E le va tio n (f ee t)

3 3/4" Boring Method:

Rock Core Diam:

Vane Shear

30 in.

140 lbs/Automatic

Penetrometer (PP in tsf)

Water Content %

Hole Diameter:

NAD83

HSA

BH20-01

Hammer Wt. & Type:

Cloudy, 30°F

MP 127.9

Standard Penetration Test Data

Project Datum:

Inspector:

R ec ft/

P P

R

Q D

Northing: 4115618.5 Easting: 584369.13

B O

R

IN

G L

O G

/1

2/

8:

M :\P

R O

JE

C

T S

\B

LR

I\2

0- 1(

2) \T

E C

H S

E R

V \G

E O

T E

C H

\S U

B S

U R

F A

C E

IN

V

E S

T

IG

A T

IO

N

\B O

R

IN

G L

O G

S \G

IN

T

\V A

E R

F O

N P

S B

LR

I 2

0-

1( 2)

.G P

J

1588.1 1587.6

1578.0

1567.0

1559.0

Sheet: 1 of 2

1.5

0.1

Silty SAND (SM), loose, brown, moist. A-2-4(0).

Possible boulder at 33 ft.

GNEISS , gray, weathered rock.

Auger Refusal at 35.3 ft.

3-5-4-6

50/2"

J-7

J-8 35.0 35.3

Project Location:

Encountered at:

After

Caved at:

Hammer Drop:

Rock Core (RQD in %)

(Blows / ft)

1589.0 ft

Undisturbed (UD)

1/8/21

Project Name:

MATERIAL DESCRIPTION

Boring No.:

Groundwater Depth:

Sample Types:

BORING LOG

1/9/21 Doug Hutchins Jason FarleyOperator:

T yp e

Weather:

SAMPLE

Plastic Limit

No groundwater was encountered during our drilling operation.

The borehole was backfilled with auger cuttings upon completion.

hrs

Remarks:

Auger Cuttings

G ra ph ic

L og

VA ERFO NPS BLRI 2020-1(2)

Density, Color, Plasticity, Size, Proportions, Moisture

Surface Elevation:

Boring Location:

La ye r

D ep th ft)

Boring Began:

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

Liquid Limit

SPT

U. S. DEPARTMENT OF TRANSPORTATION

At Completion:

Completed:

S P

T B lo w s pe r in

D ep th S ca le ft

N o.

BLRI, MP 119.7 and MP 127.9, Roanoke County, VA

E le va tio n (f ee t)

3 3/4" Boring Method:

Rock Core Diam:

Vane Shear

30 in.

140 lbs/Automatic

Penetrometer (PP in tsf)

Water Content %

Hole Diameter:

NAD83

HSA

BH20-01

Hammer Wt. & Type:

Cloudy, 30°F

MP 127.9

Standard Penetration Test Data

Project Datum:

Inspector:

R ec ft/

P P

R

Q D

Northing: 4115618.5 Easting: 584369.13

B O

R

IN

G L

O G

/1

2/

8:

M :\P

R O

JE

C

T S

\B

LR

I\2

0- 1(

2) \T

E C

H S

E R

V \G

E O

T E

C H

\S U

B S

U R

F A

C E

IN

V

E S

T

IG

A T

IO

N

\B O

R

IN

G L

O G

S \G

IN

T

\V A

E R

F O

N P

S B

LR

I 2

0-

1( 2)

.G P

J

1554.0 1553.7

Sheet: 2 of 2

2"

1.5

0.7

1.1

1.4

ASPHALT PAVEMENT

BASE COURSE

Silty SAND with gravel, medium dense, brown, moist.

Fill.

Possible cobbles at 2 ft.

Sandy SILT, very stiff, brown, moist, traces of gravel.

Fill.

Silty SAND with gravel (SM), medium dense, brown, moist, pieces of boulder. A-1-b. Fill.

Silty SAND with gravel (SM), medium dense, brown, moist, boulder pieces. A-2-4(0). Fill.

Auger Refusal at 18.6 ft.

7-5-4-10

2-9-15-11

3-9-18-16

2-3-14-11

J-1

J-2

J-3

J-4

1.0 1.5

5.0

10.0

15.0

18.6

Project Location:

Encountered at:

After

Caved at:

Hammer Drop:

Rock Core (RQD in %)

(Blows / ft)

1594.5 ft

Undisturbed (UD)

1/7/21

Project Name:

MATERIAL DESCRIPTION

Boring No.:

Groundwater Depth:

Sample Types:

BORING LOG

1/7/21 Doug Hutchins Jason FarleyOperator:

T yp e

Weather:

SAMPLE

Plastic Limit

No groundwater was encountered during our drilling operation.

The borehole was backfilled with auger cuttings upon completion.

hrs

Remarks:

Auger Cuttings

G ra ph ic

L og

VA ERFO NPS BLRI 2020-1(2)

Density, Color, Plasticity, Size, Proportions, Moisture

Surface Elevation:

Boring Location:

La ye r

D ep th ft)

Boring Began:

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

Liquid Limit

SPT

U. S. DEPARTMENT OF TRANSPORTATION

At Completion:

Completed:

S P

T B lo w s pe r in

D ep th S ca le ft

N o.

BLRI, MP 119.7 and MP 127.9, Roanoke County, VA

E le va tio n (f ee t)

3 3/4" Boring Method:

Rock Core Diam:

Vane Shear

30 in.

140 lbs/Automatic

Penetrometer (PP in tsf)

Water Content %

Hole Diameter:

NAD83

HSA

BH20-02

Hammer Wt. & Type:

Cloudy, 32°F

MP 127.9

Standard Penetration Test Data

Project Datum:

Inspector:

R ec ft/

P P

R

Q D

Northing: 4115612.56 Easting: 584338.65

B O

R

IN

G L

O G

/1

2/

8:

M :\P

R O

JE

C

T S

\B

LR

I\2

0- 1(

2) \T

E C

H S

E R

V \G

E O

T E

C H

\S U

B S

U R

F A

C E

IN

V

E S

T

IG

A T

IO

N

\B O

R

IN

G L

O G

S \G

IN

T

\V A

E R

F O

N P

S B

LR

I 2

0-

1( 2)

.G P

J

1593.5 1593.0

1589.5

1584.5

1579.5

1575.9

Sheet: 1 of 1

APPENDIX D – LABORATORY TESTING RESULTS

SOIL DATA

NO.

AASHTODESCRIPTION

DEPTHSAMPLE

SOURCESYMBOL

Project No.:

Project:

Client:

Particle Size Distribution Report

P E

R C

E N

T F

IN

E

R

100 10 1 0.1 0.01 0.001200 GRAIN SIZE - mm

% COBBLES

% GRAVEL

CRS. FINE

% SAND

CRS. MEDIUM FINE

% FINES

SILT CLAY

in in in

1- 1/ in in

3/ in

1/ in

3/ in

#4 #1

#2

#3

#4

#6

#1

#1

#2

0.0 5.8 7.9 8.2 28.1 23.3 26.7

(ft.)

VA ERFO NPS BLRI 2020-1(2)

BLRI

FHWA

BH01/J3 10-12 Silty sand A-2-4(0)

Particle Size Distribution Report

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

0.0 0.0 0.3 1.6 32.4 35.4 30.3

BH01/J5 20-22 Silty sand A-2-4(0)

27.8 28.5 43.4

BH01/J6 25-27 SILTY SAND A-4(0)

0.0 0.0 0.2 3.2 35.3 26.2 35.1

BH01/J-7 30-32 Silty sand A-2-4(0)

0.0 5.7 20.7 13.3 26.4 15.0 18.9

BH02/J3 10-12 Silty sand with gravel A-1-b

NO.

AASHTODESCRIPTION

DEPTHSAMPLE

SOURCESYMBOL

Project No.:

Project:

Client:

Particle Size Distribution Report

P E

R C

E N

T F

IN

E

R

100 10 1 0.1 0.01 0.001200 GRAIN SIZE - mm

% COBBLES

% GRAVEL

CRS. FINE

% SAND

CRS. MEDIUM FINE

% FINES

SILT CLAY

in in in

1- 1/ in in

3/ in

1/ in

3/ in

#4 #1

#2

#3

#4

#6

#1

#1

#2

0.0 11.7 7.8 4.8 27.1 21.8 26.8

(ft.)

VA ERFO NPS BLRI 2020-1(2)

BLRI

FHWA

BH02/J4 15-17 Silty sand with gravel A-2-4(0)

Particle Size Distribution Report

INDEXLIMITLIMITCONTENTNO.

PLASTICITYLIQUIDPLASTICWATERDEPTHSAMPLE

NATURAL

SOURCESYMBOL

Project No.:

Project:

Client:

LIQUID AND PLASTIC LIMITS TEST REPORT

(ft.)

AASHTO

VA ERFO NPS BLRI 2020-1(2)

BLRI

FHWA

A-2-4(0)10362617.210-12BH01/J3

LIQUID AND PLASTIC LIMITS TEST REPORT

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

A-2-4(0)NPNVNP22.820-22BH01/J5

A-4(0)NPNVNP26.625-27BH01/J6

A-2-4(0)NPNVNP24.830-32BH01/J-7

A-1-bNPNVNP7.410-12BH02/J3

10 30 50 70 90 110

LIQUID LIMIT

P

LA

S T

IC

IT

Y

IN

D E

X

PI

=L

L-

A-4 or A-2-4 A-5 or A-2-5

A-7-6

A-6 or A-2-6

A-7-5 or A-2-7

INDEXLIMITLIMITCONTENTNO.

PLASTICITYLIQUIDPLASTICWATERDEPTHSAMPLE

NATURAL

SOURCESYMBOL

Project No.:

Project:

Client:

LIQUID AND PLASTIC LIMITS TEST REPORT

(ft.)

AASHTO

VA ERFO NPS BLRI 2020-1(2)

BLRI

FHWA

A-2-4(0)NPNVNP14.615-17BH02/J4

LIQUID AND PLASTIC LIMITS TEST REPORT

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

10 30 50 70 90 110

LIQUID LIMIT

P

LA

S T

IC

IT

Y

IN

D E

X

PI

=L

L-

A-4 or A-2-4 A-5 or A-2-5

A-7-6

A-6 or A-2-6

A-7-5 or A-2-7

Sample # E-21- Jar # Wet Wt (g) Dry Wt (g) Jat Wt (g)

Total Sample Wt (g)

T-265 MC

0022 01/J-3 1032.7 944.8 434.8 510.0 17.2 0023 01/J-5 1148.3 1015.6 434.8 580.8 22.8 0024 01/J-6 1281.3 1103.7 434.8 668.9 26.6 0025 01/J-7 1255.7 1092.7 434.8 657.9 24.8 0026 02/J-3 1141.2 1092.4 434.8 657.6 7.4 0027 02/J-4 1322.5 1209.3 434.8 774.5 14.6

APPENDIX E – SLOPE STABILITY ANALYSES

2.0172.0172.0172.017

RuWater SurfaceAllow Sliding

Phi (deg)

Cohesion (psf)Strength TypeUnit Weight (lbs/ ft3)ColorMaterial Name

0None300Mohr‐Coulomb115Fill

0None320Mohr‐Coulomb120Colluvium ‐ Sand (SC/SM) or Clay/Silt (CL/

ML)

0None380Mohr‐Coulomb135Rock

0NoneYesInfinite strength125Rolled Erosion Control

0None340Mohr‐Coulomb115Structural Backfill

Force OrientationMaterial Dependent

Bond Strength (lbs/ft)

Compression Capacity (lbs)

Shear Capacity (lbs)

Plate Capacity (lbs)

Tensile Capacity (lbs)

Out‐Of‐Plane Spacing (ft)

Force ApplicationTypeColorSupport

Name

Parallel to Reinforcement

No270000250002500010Active (Method A)

Soil Nail

SoilNail

10.000 15°

Safety Factor 0.000 0.250 0.500 0.750 1.000 1.250 1.500 1.750 2.000 2.250 2.500 2.750 3.000 3.250 3.500 3.750 4.000 4.250 4.500 4.750 5.000 5.250 5.500 5.750 6.000+

-60 -40 -20 0 20 40 60 80 100

Analysis Description SoilNails+Static Company FHWA-EFLScale 1:200Drawn By GW File Name MP 119.7 - Sta. 201+60.slmdDate 7/8/2021 2:49:51 PM

Project

KY ERFO 2019-1(1)

SLIDEINTERPRET 9.017

1.8601.8601.8601.860

0.037

Safety Factor 0.000 0.250 0.500 0.750 1.000 1.250 1.500 1.750 2.000 2.250 2.500 2.750 3.000 3.250 3.500 3.750 4.000 4.250 4.500 4.750 5.000 5.250 5.500 5.750 6.000+

-60 -40 -20 0 20 40 60 80 100

Analysis Description SoilNails+Seismic Company FHWA-EFLScale 1:200Drawn By GW File Name MP 119.7 - Sta. 201+60.slmdDate 7/8/2021 2:49:51 PM

Project

KY ERFO 2019-1(1)

1.3151.315

250.00 lbs/ft2

1.3151.315

1.500

35.000

31.000

0.65

RuWater Surface

Phi (deg)

Cohesion (psf)Strength TypeUnit Weight (lbs/ ft3)ColorMaterial Name

0None300Mohr‐ Coulomb115Fill

0None320Mohr‐ Coulomb120Colluvium ‐ Sand (SC/SM) or Clay/Silt (CL/

ML)

0None380Mohr‐ Coulomb135Rock

0None340Mohr‐ Coulomb115Granular Backfill

Connection Strength (lbs/ft)

Connection Strength Input

Long Term Design

Strength (lbs/ ft)

Strip Coverage

AnchorageForce

Orientation

Shear Strength Model

Friction Angle (deg)

Adhesion (psf)

Material Dependent

Force ApplicationTypeColorSupport

Name

2500Constant2500100Slope FaceParallel to ReinforcementLinear240YesPassive

(Method B)GeosyntheticGeogrid

Safety Factor 0.000 0.250 0.500 0.750 1.000 1.250 1.500 1.750 2.000 2.250 2.500 2.750 3.000 3.250 3.500 3.750 4.000 4.250 4.500 4.750 5.000 5.250 5.500 5.750 6.000+

-200 -150 -100 -50 0 50 100

Analysis Description RSS+Static Company FHWA-EFLScale 1:400Drawn By GW File Name MP 127.9 - Sta. 101+00.slmdDate 7/8/2021 2:56:20 PM

Project

1.2221.222

250.00 lbs/ft2

1.2221.222

0.039

Safety Factor 0.000 0.250 0.500 0.750 1.000 1.250 1.500 1.750 2.000 2.250 2.500 2.750 3.000 3.250 3.500 3.750 4.000 4.250 4.500 4.750 5.000 5.250 5.500 5.750 6.000+

-200 -150 -100 -50 0 50 100

Analysis Description RSS+Seismic Company FHWA-EFLScale 1:400Drawn By GW File Name MP 127.9 - Sta. 101+00.slmdDate 7/8/2021 2:56:20 PM

Project

APPENDIX F – SELECTED PHOTOGRAPHS

Photo No. 1: Landslide scarp (looking east), MP 127.9

Photo No. 2: Extent of scarp (looking south east), MP 127.9

Photo No. 3: Location of BH20-01, MP 127.9

Photo No. 4: Location of BH20-02, MP 127.9

Photo No. 5: Panoramic photo of landslide scarp (looking south), MP 119.7

Photo No. 6: Landslide scarp (looking west), MP 119.7

Photo No. 7: Location of scarp is on a curve. (looking west), MP 119.7