Reams_Rd_Final_Geotech_Bridge_Report.pdf

Prepared for:

DRMP, Inc.

941 Lake Baldwin Lane

Orlando, FL 32814

Prepared by:

Nadic Engineering Services, Inc.

601 N. Hart Blvd

Orlando, Florida 32818 407-521-4771

Consultants in: Civil ꞏ Environmental ꞏ Geotechnical Engineering Offices in: Orlando ꞏ Miami

Final Geotechnical Bridge Report Final Design of Reams Road

(From South of Summerlake Park Blvd to Taborfield Avenue)

Orange County, Florida Orange County Project No.: Y19-804-CH NADIC Project No. PR.GEO-RD19013

January 21, 2026

DRMP, INC.

941 Lake Baldwin Lane Orlando, FL 32814

Attention: Ms. Colette Moss, P.E.

Executive Vice President of Transportation

RE: Final Geotechnical Bridge Report Final Design of Reams Road (From South of Summerlake Park Blvd to Taborfield Avenue) Orange County, Florida Orange County Project No.: Y19-804-CH NADIC Project No.: PR.GEO-RD19013

Dear Ms. Moss:

Nadic Engineering Services, Inc. (NADIC) is pleased to submit this Final Geotechnical Bridge Report for the proposed bridge along Reams Road from South of Summerlake Park Blvd to Taborfield Avenue. The bridge is located just East of Greenbank Boulevard in Orange County, Florida. The purpose of this report is to explore the subsurface conditions at the bridge site and use the geotechnical information obtained to evaluate and provide recommendations to support the design and construction of the proposed Reams Road Bridge.

This report describes our exploration, laboratory testing and includes our preliminary foundation alternatives analyses.

NADIC appreciates the opportunity to be of service to DRMP and Orange County Public Works Department on this project. We trust this information is sufficient for the Final submittal. If you have any questions regarding the contents of this report, please contact the undersigned.

Sincerely, NADIC ENGINEERING SERVICES, INC.

Engineering Business No. 8064

Maria Bridges, M.Sc. Godwin N. Nnadi, Ph.D., P.E.

Engineer Intern Principal Engineer

FL Registration No. 50637

Cc: Mike Waddell, P.E. – TLP

S:\New Z Drive\Engineering\Geotechnical\Orlando\Roadway (RD)\2019\PR.GEO-RD19013- Reams Road Reconstruction3\Project Working \\Report\

Godwin Nnadi Dr. Nnadi Stamp

DRMP January 21, 2026 Reams Road – Bridge Report NADIC Project No.: PR.GEO-RD19013 i of ii

NADIC

TABLE OF CONTENTS

1.0 PROJECT DESCRIPTION

2.0 REVIEW OF AVAILABLE DATA

2.1 USGS Topographic Map

2.2 Orange County USDA/NRCS Soil Survey

2.3 Potentiometric Surface Map

2.4 Generalized Geology

2.5 Sinkhole Potential

3.0 FIELD EXPLORATION PROGRAM AND METHODS

3.1 Field Exploration Program

3.2 Field Exploration Methods

3.2.1 Standard Penetration Test Borings

4.0 SUBSURFACE CONDITIONS

4.1 Bridge Boring Results

4.2 Retaining Wall Boring Results

4.3 Groundwater Conditions

4.4 Sinkhole Risk

5.0 LABORATORY TESTING

6.0 EVALUATION AND RECOMMENDATIONS

6.1 Foundation Alternatives

6.2 Selected Foundation System

6.3 Axial Capacity for Piles

6.4 Estimated Pile Tip Elevation

6.5 Downdrag Considerations/Embankment Settlement

6.6 Lateral Load Consideration

6.7 Pile Group Action

6.8 Pile Settlement

6.9 Test Pile Program

6.10 Protection of Existing Structures

6.11 Proprietary Walls – Bridge Abutments

6.12 CIP Cantilever Walls

6.13 Weir Wall

NADIC Project No.: PR.GEO-RD19013 ii of ii

TABLE OF CONTENTS CONTINUED

6.14 Environmental Classification

6.15 Excavations

7.0 FHWA REPORT CHECKLIST

8.0 REPORT LIMITATIONS

APPENDICES

APPENDIX A Figure 1 Vicinity Map Figure 2 USGS Topographic Map Figure 3 USDA/NRCS Soils Map Figures 4A and 4B Boring Location Map Table 5 Summary of Laboratory Test Results Table 8 FL-Pier Soil Parameters Table 12 Geotechnical Information for MSE Walls

APPENDIX B Sheets 1 through 4 Report of Bridge Borings Sheets 5 through 7 Report of Wall Borings

APPENDIX C Plates 1 through 4 Axial Capacity Design Curves – 24-inch Precast Prestressed Concrete Piles

APPENDIX D Plates 5 through 8 Axial Capacity Design Curves – 18-inch Precast Prestressed Concrete Piles Plates 9 through 12 Axial Capacity Design Curves – Steel Piles FB-Deep Output Files

APPENDIX E Settlement Analysis Downdrag Analysis Slope Stability Analysis MSE Wall LRFD External Stability Analysis

APPENDIX F FHWA Checklist

NADIC Project No.: PR.GEO-RD19013 Page 1 of 25

1.0 PROJECT DESCRIPTION

This project is a part of the proposed Ream Road widening and reconstruction from South of Summerlake Park Boulevard to Taborfield Avenue, Orange County plans to replace the existing Box Culvert for stormwater and wildlife crossing with a bridge across Ream Road. The existing Box Culvert was originally planned to be replaced by a longer box culvert, however; based on the results of NADIC subsurface exploration, buried organic soils (muck) were encountered between Station 417+50 and 420+00. The encountered muck extends as deep as elevation +16 feet NAVD-88. The existing road elevation is about +98.3 and planned to be raised to about elevation +110. Due to the anticipated settlement expected from the buried muck, environmental concerns, and cost of construction and maintenance, a bridge crossing is found to be a feasible option.

The project major elements of Reams Road reconstruction also include the following:

Construction of four (4) lanes for Reams Road from South of Summerlake Park Boulevard to Taborfield Avenue, a 14-foot concrete multiuse trail on the left side, and a 5-foot concrete sidewalk on the right side

Special treatment and/or additional lanes at major intersections, and widening of crossroads up to 600 feet in each direction

Construction of five (5) new stormwater ponds and one (1) floodplain compensation pond Two (2) pavement coring within project limits Total of 17 traffic mast arms Approximately 2,500 linear feet of retaining walls

This report deals specifically with the proposed Reams Road Bridge. Approximate limits of the proposed bridge are presented below in Table 1.

Table 1 Proposed Bridge Information

Bridge No.

Station* Span

Lengths (feet)

No of Spans

Overall Length (feet)

Estimated Embankment Height (feet)

Begin End

754194 417+50.0 420+35.0 95 3 285 ~16 *Base Line of Survey: CL Const. Ream Road

An approximate location of the bridge structure is shown on the Vicinity Map in Figure 1 in Appendix A.

The following report presents the findings of our subsurface exploration program, an evaluation of the soil and groundwater conditions, and provides preliminary recommendations to guide design of the proposed bridge.

In accordance to the current Florida Department of Transportation (FDOT) guidelines, the pile for the bridge expansions will be designed using the Load and Resistance Factor Design (LRFD) method.

NADIC Project No.: PR.GEO-RD19013 Page 2 of 25

2.0 REVIEW OF AVAILABLE DATA

2.1 USGS Topographic Map

The “Windermere, Florida” USGS Topographic Maps issued in 2024, along the project alignment were reviewed. Excerpts of the USGS Topographic Maps are presented on Figure 2 in Appendix A. The map shows the ground surface elevation in the project vicinity to be approximately +100 feet North American Vertical Datum of 1988 (NAVD-88).

2.2 Orange County USDA/NRCS Soil Survey

The "Soil Survey of Orange County, Florida", published by the United States Department of Agriculture (USDA), Natural Resources Conservation Service (NRCS), was reviewed for general near-surface soil information within the general project vicinity of the Reams Road Stormwater & Wildlife Bridge site. The mapped soil unit encountered is as follows.

Table 2 NRCS Soil Survey Summary

Soil Name (Unit No.)

Depth (Inches)

Soil Description

Unified Classification

Soil

AASHTO*

Depth of Seasonal High Groundwater

(feet)

Risk of Corrosion

Uncoated Steel

Concrete

Basinger (3)

0-7 Fine Sand SP A-3

0 – 1.0 High Moderate 7-32 Sand, Fine Sand SP, SP-SM A-3, A-2-4

32-47 Sand, Fine Sand SP, SP-SM A-3, A-2-4 47-80 Sand, Fine Sand SP, SP-SM A-3, A-2-4

Immokalee (20)

0-5 Fine Sand SP, SP-SM A-3

0.5 – 1.0 High High 5-35 Fine Sand, Sand SP, SP-SM A-3

35-67 Fine Sand, Sand SP-SM, SM A-3, A-2-4 67-80 Fine Sand, Sand SP, SP-SM A-3

Samsula

(41)

Hontoon (41)

0-34 Muck PT A-8

0 High High

34-80 Sand, Fine Sand, Loamy Sand

SP-SM, SM, SP A-3, A-2-4

0-34 Muck PT A-8

0-80 Muck PT A-8

Basinger (41)

0-6 Fine Sand SP A-3 6-25 Sand, Fine Sand SP, SP-SM A-3, A-2-4

25-35 Sand, Fine Sand SP, SP-SM A-3, A-2-4 35-80 Sand, Fine Sand SP, SP-SM A-3, A-2-4

NADIC Project No.: PR.GEO-RD19013 Page 3 of 25

Table 2 Continued NRCS Soil Survey Summary

*AASHTO: American Association of State Highway and Transportation Officials

A reproduction of the USDA/NRCS soils map for the project area is illustrated on Figure 3 in Appendix A of this report. The information contained in the NRCS Soil Survey is very general and may be outdated due to recent development in the site vicinity. These developments may have modified soil condition or surface subsurface drainage.

2.3 Potentiometric Surface Map

Based on review of data provided by the Florida Department of Environmental Protection, Florida Geological Survey titled “Upper Floridian Aquifer Potentiometric Surface, Florida, 2021”, the elevation of the potentiometric surface in the vicinity of the project alignment appears to be about +75 to +90 feet, North American Vertical Datum of 1988 (NAVD-88).

2.4 Generalized Geology

Orange County is underlain by a thick sequence of limestone and dolostones upon which a relatively thin section of clastics (sand, silt, shell material, and clay) was deposited. The deepest formation normally encountered is the Avon Park Limestone Formation of Middle Eocene age. It consists mostly of hard, brown dolostone and some tan, granular limestone. In Orange County, the Avon Park Limestone Formation is approximately 300 to 350 feet thick. The Ocala Limestone Formation of late Eocene age is underlain by the Avon Park Limestone Formation. It consists of a loose to moderately well cemented mass of very small to large microfossils with much less dolostone when compared to the Avon Park Limestone. Typically, the Ocala Limestone contains almost pure limestone with no dolostone, although the lower few feet can be partly dolomitized in some areas.

Overlying the Ocala Limestone is the Hawthorn Group of Miocene age, which consists of sand, silt, clay and some limestone or dolostone beds. The thickness of the Hawthorn Group is generally between 0 and 130 feet. The clastic material overlying the Hawthorn Group consists of sand, clay, and shell material. Generally, sandy or clayey shell material directly overlies the Hawthorn Group

Soil Name (Unit No.)

Depth (Inches)

Soil Description

Unified Classification

Soil

AASHTO*

Depth of Seasonal High Groundwater

(feet)

Risk of Corrosion

Uncoated Steel

Concrete

Smyrna- Smyrna

(44)

0-17 Fine Sand SP, SP-SM A-3, A-2-4

0.5 – 1.5 High High 17-27

Sand, Fine Sand, Loamy Fine Sand

SM, SP-SM A-3, A-2-4

27-80 Sand, Fine Sand SP, SP-SM A-3 0-17 Fine Sand SP, SP-SM A-3, A-2-4

Zolfo (54)

0-5 Fine Sand SP-SM A-3, A-2-4

1.5 – 3.5 Low Moderate 5-55 Fine Sand, Sand SP-SM, SM A-3, A-2-4

55-80 Fine Sand, Sand SP-SM, SM A-3, A-2-4

NADIC Project No.: PR.GEO-RD19013 Page 4 of 25 with clayey sand overlying that material and relatively pure sand extending from there to the surface.

2.5 Sinkhole Potential

The geology of the area, as described above, is conducive to the development of sinkholes. The solution features within the limestone can collapse or can allow the downward movement of overlying soils, known as raveling, to produce depressions at the surface which are typically circular in shape (sinkholes). Sinkholes can occur nearly anywhere in Central Florida but are more likely to occur in areas characterized by thin confining beds, large differences between the surface water table elevation and the Floridian Aquifer potentiometric level, high recharge characteristics and the presence of limestone in relatively close proximity to the ground surface. Based on review of the U.S. Geological Survey Map entitled “Recharge and Discharge Areas of the Floridan Aquifer in the St. Johns River Water Management District and Vicinity, Florida,” 1984, the portion of the proposed bridge widening in Orange County and results of the limited subsurface exploration results performed at the site, the site is in an area that is considered to be low risk of recharge/sinkhole occurrence in Central Florida.

3.0 FIELD EXPLORATION PROGRAM AND METHODS

3.1 Field Exploration Program

The subsurface exploration performed by NADIC consisted of a total of eight (8) Standard Penetration Test (SPT) borings at the proposed bridge foundation piers and eight (8) SPT borings for the proposed retaining walls. The SPT borings were drilled to depths ranging from 20 to 175 feet below existing grade.

The boring locations were established in the field based on information provided by NADIC and approved by TLP, the Project Structural Engineer. All borings were staked in the field by a representative of NADIC with the aid of a hand-held Garmin GPSMAP64st Global Positioning Satellite (GPS) device. The station, offset and elevation at each SPT boring location were provided by DRMP.

Upon completion and after groundwater measurements, all borings were grouted and backfilled for safety. The approximate SPT boring locations are shown on Figures 4A and 4B in Appendix A.

NADIC Project No.: PR.GEO-RD19013 Page 5 of 25

3.2 Field Exploration Methods

3.2.1 Standard Penetration Test Borings

The SPT borings were performed at boring locations in general conformance with American Society for Testing and Materials (ASTM) test designation D-1586. The borings were advanced by the rotary wash method with bentonite-based mud as the circulating fluid to stabilize the borehole. The SPT borings were generally performed continuously from the ground surface to 12.5 feet and at 5-foot depth intervals thereafter. After seating the sampler six inches, the number of successive blows required to drive the sampler 12 inches into the soil constitutes the test result commonly referred to as the “N” value. Adjacent to the SPT boring profiles on Sheets 1 through 7 in Appendix B are the “N” values. The “N” value has been empirically correlated with various soil properties and is considered indicative of the relative density of cohesionless soils and the consistency of cohesive soils.

The recovered split-barrel samples were described in the field with representative portions of the samples placed in airtight bags and transported to our office for visual classification and laboratory testing.

Upon completion of groundwater level measurement, each borehole was sealed with cement grout.

4.0 SUBSURFACE CONDITIONS

The soils encountered were classified using the Unified Soil Classification System (USCS) (e.g., SP, SM). Soils were described using the ASTM soil descriptions such as sand with silt. Soil classification and stratification are based on visual examination, interpretation of the boring logs by a geotechnical engineer and laboratory results of selected soil samples. Stratification lines represent the approximate boundaries between different soil types. However, actual transition between soils may be gradual and different than indicated. The soil profiles indicate subsurface conditions encountered only at the specific boring locations at the time of the field exploration.

Moreover, conditions at the boring locations can change over time. The results of the borings are presented in the form of soil profiles on Sheets 1 through 7 in Appendix B. Included with the soil profiles are the groundwater levels measured at the time the borings were performed and the estimated seasonal high groundwater levels.

The following generalized soil descriptions are intended to provide a summary of the observed subsurface conditions at the bridge location. A specific description of the soil conditions and relative density is provided by the soil profiles.

NADIC Project No.: PR.GEO-RD19013 Page 6 of 25

4.1 Bridge Boring Results

A total of eight (8) SPT Borings were performed at the proposed bridge foundation piers to depths ranging from 140 to 175 feet below existing grade. Soils encountered in the borings generally consisted of fine sand with varying amounts of fines followed by alternating layers of silty sand, clayey sand and sandy clay above limestone and silty sand deposits to boring termination depths.

Borings EB-1B, IB-2A, IB-2B, IB-3A and IB-3B encountered organic silty sand to peat at elevations ranging from about +11 to + 94.5 feet, NAVD-88.

Generalized subsurface conditions encountered in the borings are presented below in Table 3.

Table 3 Generalized Subsurface Profiles: Bridge

Boring No.

(Station, Offset)

Approx.

Elevation

(ft, NAVD-88) Soil Description

Typical Range of N-Values (blows/ft)

EB-1A

(417+50, 21’ LT)

+98.9 – +81.4 Loose to very dense dark brown to brown fine SAND with silt, organics and roots

(SP-SM)

4 – 30

+81.4 – +15.1 Alternative layers of loose to very dense gray to light brown silty SAND (SM) and clayey SAND (SC) with interbedded very stiff light gray sandy CLAY (CL) occasionally with phosphate and limestone fragments and cemented sands

3 – 24

+15.1 – -41.1 Medium dense to very dense light brown silty LIMESTONE (LS) 24 – 50/3”

EB-1B

(417+49, 2’ LT)

+98.5 – +94.5 Very loose brown to gray fine SAND with clay, trace limerock fragments, (SP-SC) 3*

+94.5 – +92.5 Very loose dark gray organic silty SAND with roots, (PT) 2

+92.5 – +16.0 Alternative layers of very loose to very dense brown to gray silty SAND (SM), clayey SAND (SC) and very soft to hard sandy CLAY (CL, CH) occasionally with limestone fragments

1 – 50/5”

+16.0 – -31.0 Medium dense to very dense light brown silty LIMESTONE (LS) 15 – 50/3”

-31.0 – -51.5 Medium dense to very dense light brown silty SAND, trace limestone fragments

(SM)

14 – 50/3”

IB-2A

(418+50, 29’ LT)

+98.2 – +90.2 Very loose to loose brown to gray fine SAND with silt, occasionally trace limerock fragments (SP-SM)

3 – 6

+90.2 – +85.7 Very soft dark brown PEAT (PT) WH

+85.7 – +65.7 Very loose to medium dense dark brown fine SAND with silt, occasionally with organics (SP-SM)

1 – 9

+65.7 – +15.7 Very loose to medium dense light brown to brown clayey SAND (SC) WH – 9

+15.7 – -76.8 Alternative layers of loose to very dense light brown silty LIMESTONE (LS), medium dense to very dense light brown silty SAND with limestone fragments (SM) and stiff to very stiff light brown sandy SILT with limestone fragments (ML)

7 – 50/2”

3* = Assumed “N” value for hand augered depth WH = Weight of hammer

NADIC Project No.: PR.GEO-RD19013 Page 7 of 25

Table 3 Continued

Offset)

Approx.

Elevation

(ft, NAVD-88) Soil Description

Typical Range of N-Values (blows/ft)

IB-2B

(418+51, 1’ LT)

+98.3 – +90.8 Very loose to medium dense gray fine SAND with silt (SP-SM) 3* – 12

+90.8 – +86.3 Very soft to stiff dark brown PEAT (PT) 1 – 8

+86.3 – +66.3 Very loose to medium dense dark brown to brown fine SAND with silt and organics (SP-SM)

WH – 11

+66.3 – +20.8 Very soft to firm light brown sandy CLAY (CH) followed by very loose to medium dense light brown to gray silty SAND (SM) and clayey SAND with limestone fragments (SC)

1 – 15

+20.8 – -51.7 Alternative layers of medium dense to very dense light brown silty LIMESTONE (LS) and silty SAND with limestone fragments (SM)

13 – 100

IB-3A

(419+45, 25’ LT)

+98.2 – +92.2 Very loose to loose reddish brown to gray fine SAND with silt (SP-SM) 3* – 8

+92.2 – +90.2 Soft dark gray organic silty SAND (PT) 2

+90.2 – +65.7 Very loose to loose dark gray to brown silty SAND occasionally with organics and roots (SM) with an interbedded later of gray to dark gray fine SAND with silt (SP-

SM)

1 – 5

+65.7 – +10.7 Firm light gray sandy CLAY (CH) followed by medium dense brown silty SAND (SM) and very loose to dense brown to gray clayey SAND (SC) occasionally with limestone fragments and organics

WH – 29

+10.7 – -76.8 Alternative layers of loose to very dense light brown silty LIMESTONE (LS), dense to very dense light brown silty SAND with limestone fragments (SM) and soft to very stiff light brown sandy SILT with limestone fragments (ML)

2 – 50/1”

IB-3B

(419+45, 2’ LT)

+98.3 – +92.3 Very loose to loose yellowish brown to light brown fine SAND with clay, trace limerock fragments (SP-SC) to dark gray fine SAND with silt (SP-SM)

3* – 8

+92.3 – +90.3 Soft dark gray PEAT (PT) 2

+90.3 – +22.5 Very loose to loose dark gray fine SAND with silt, occasionally with organics and roots (SP-SM)

1 – 4

+22.5 – +15.8 Alternative layers of very loose to dense dark brown to brown silty SAND (SM) to clayey SAND (SC) followed by a layer of dense light brown silty LIMESTONE

(LS)

WH – 39

+15.8 – +10.8 Soft dark brown PEAT (PT) 2

+10.8 – -76.7

Alternative layers of very loose to very dense light brown silty SAND with limestone fragments (SM) and medium dense to very dense light brown silty LIMESTONE (LS) with interbedded layer of stiff light brown sandy SILT with limestone fragments (ML)

WH – 50/3”

NADIC Project No.: PR.GEO-RD19013 Page 8 of 25

Table 3 Continued

Offset)

Approx.

Elevation

(ft, NAVD-88) Soil Description

Typical Range of N-Values (blows/ft)

EB-4A

(420+45, 45’LT)

+97.4 – +79.9 Very loose to medium dense gray to brown fine SAND with silt (SP-SM) with interbedded layer of medium dense gray clayey SAND (SC)

3* – 9

+79.9 – +24.9 Very loose to very dense gray to brown clayey SAND with limestone and shell fragments (SC) with interbedded layer of very loose light gray silty SAND (SM) and hard gray sandy CLAY (CL)

3 – 50/6”

+24.9 – -25.1 Medium dense to very dense light brown silty LIMESTONE (LS) 13 – 50/3”

-25.1 – -77.6 Alternative layers of gray o light brown medium dense to very dense silty SAND (SM), light brown silty LIMESTONE (LS) and firm light brown sandy SILT (ML)

5 – 50/3”

EB-4B

(420+35, 32’RT)

+97.5 – +80.0 Loose to medium dense brown to gray fine SAND with silt (SP-SM) 3 – 16

+80.0 – +23.5 Very loose to very dense gray to brown clayey SAND with limestone and shell fragments (SC)

2 – 57

+23.5 – -25.5 Medium dense to very dense LIMESTONE with silt and shell fragments (LS) 22 – 50/1”

-25.5 – -52.5 Dense light brown silty SAND with interbedded very dense LIMESTONE (LS) 27 – 50/2”

3* = Assumed “N” value for hand augered depth

Total loss of drill fluid circulation was observed in most of the bridge borings at elevations ranging from about +13 to -52 feet, NAVD-88 except Borings EB-1A, IB-3B and EB-4A.

Detailed information on specific strata encountered within the borings is presented in the form of soil profiles as Report of SPT Borings on Sheets 1 through 4 in Appendix B.

4.2 Retaining Wall Boring Results

A total of eight (8) SPT Borings were performed within the proposed retaining walls to depths ranging from 20 to 60 feet below existing grade. Soils encountered in the borings generally consisted of fine sand with varying amounts of fines followed by clayey sand and sandy clay to boring termination depths. Boring W-2 encountered peat from existing ground surface to an elevation of about +88.5 feet, NAVD-88.

Information from Bridge Borings EB-1A, EB-1B, EB-4A, and EB-4B, extending to 40 feet below the existing grade, was used in the evaluation of the MSE walls.

NADIC Project No.: PR.GEO-RD19013 Page 9 of 25

Table 4 Generalized Subsurface Profiles: Retaining Walls

Wall ID

(Station, Offset)

Approx.

Elevation

(ft, NAVD-88) Soil Description

Typical Range of N-Values (blows/ft)

CIP Wall 3

SW-1

(376+16, 42’ RT)

+100 – +94 Loose to medium dense gray fine SAND with silt (SP-SM) to loose grayish brown silty SAND (SM)

7 – 13

+94 – +80 Loose to medium dense light gray clayey SAND (SC) with interbedded layer of firm to stiff gray with yellow stain sandy CLAY

(CH)

7 – 17

SW-2

(377+58, 38’ RT)

+102.2 – +96.2 Loose to medium dense dark brown fine SAND with silt and organics (SP-SM)

7 – 20

+96.2 – +82.2 Medium dense brownish gray clayey SAND (SC) to firm to stiff gray with yellow stain sandy CLAY (CH)

7 – 24

SW-3

(379+03, 39’ RT)

+99.1 – +91.1 Very loose to medium dense dark brown fine SAND with silt and roots (SP-SM)

3 – 14

+91.1 – +79.1 Very loose to medium dense brownish gray clayey SAND (SC) to firm gray sandy CLAY (CH)

6 – 15

SW-4

(380+54, 39’ RT)

+96.7 – +92.7 Loose to medium dense brown to gray fine SAND with silt (SP-SM) 5 – 10

+92.7 – +76.7 Loose to medium dense gray with yellow stain clayey SAND (SC) to stiff gray with yellow stain sandy CLAY (CH) to loose gray with yellow stain silty SAND (SM)

5 – 24

CIP Wall 1

MSE Wall 1

W-1 (416+70, 47’ LT)

+98.7 – +90.7 Very loose brown to dark brown fine SAND with silt and limerock fragments (SP-SM)

3*

+90.7 – +38.7 Loose to very dense light brown to light gray to dark greenish gray clayey SAND, occasionally with limestone and shell fragments (SC)

4 – 50/5”

MSE Wall 1

EB-1A

(417+50, 21’ LT)

+98.9 – +81.4 Loose to very dense dark brown to brown fine SAND with silt, organics and roots (SP-SM)

4 – 30

+81.4 – +58.9 Alternative layers of loose to medium dense gray silty SAND (SM) and gray to brown clayey SAND (SC)

3 – 10

EB-1B

(417+49, 2’ LT)

+98.5 – +94.5 Very loose brown to gray fine SAND with clay, trace limerock fragments, (SP-SC)

3*

+94.5 – +92.5 Very loose dark gray organic silty SAND with roots, (PT) 2

+92.5 – +58.5 Alternative layers of very loose to medium dense brown to gray silty SAND (SM), clayey SAND (SC) and very soft gray to brown sandy

CLAY (CL, CH)

1 – 10

W-4 (416+73, 47’ RT)

+94.7 – +86.7 Loose to medium dense gray to brown fine SAND with silt (SP-SM) 5 – 17

+86.7 – +77.2 Firm to stiff light gray sandy CLAY (CH) 6 – 10

+77.2 – +34.7 Very loose to very dense gray to brown clayey SAND, occasionally with shell and limestone fragments, (SC)

2 – 50/5”

NADIC Project No.: PR.GEO-RD19013 Page 10 of 25

Table 4 Continued Generalized Subsurface Profiles: Retaining Walls

Wall ID

(Station, Offset)

Approx.

Elevation

(ft, NAVD-88) Soil Description

Typical Range of N-Values (blows/ft)

CIP Wall 2

MSE Wall 1

W-4A (415+28, 43’ RT)

+96.8 – +90.8 Medium dense brown to dark brown silty SAND with organics (SM) 9 – 12

+90.8 – +56.8 Loose to medium dense light brown to light gray clayey SAND, occasionally with shell fragments (SC)

5 – 18

Weir Wall W-2

(418+31, 66’ LT)

+94.5 – +88.5 Very soft dark brown PEAT, trace roots (PT) WH

+88.5 – +72.0 Very loose to medium dense dark brown to light gray fine SAND with silt, trace organics (SP-SM) to fine SAND, trace silt (SP)

1 – 14

+72.0 – +34.5 Loose to dense brown to gray clayey SAND (SC) 4 – 28

MSE Wall 2

EB-4A

(420+45, 45’LT)

+97.4 – +79.9 Very loose to medium dense gray to brown fine SAND with silt (SP- SM) with interbedded layer of medium dense gray clayey SAND

(SC)

3* – 9

+79.9 – +57.4 Very loose to medium dense gray to dark gray clayey SAND with limestone and shell fragments (SC) with interbedded layer of very loose light gray silty SAND (SM)

3 – 14

EB-4B

(420+35, 32’RT)

+97.5 – +80.0 Loose to medium dense brown to gray fine SAND with silt (SP-SM) 3 – 16

+80.0 – +57.5 Very loose to medium dense gray to brown clayey SAND with shell fragments (SC)

2 – 13

Drilling fluid losses were not encountered in any of the retaining wall borings.

Detailed information on specific strata encountered within the borings is presented in the form of soil profiles as Report of SPT Borings on Sheets 5 through 7 in Appendix B.

4.3 Groundwater Conditions

Groundwater was encountered in the borings at elevations ranging approximately +91 to +96 feet, NAVD-88 at the time of our field exploration (April 2022, March 2023, February 2025, April 2025, June 2025, July 2025 and December 2025). Groundwater levels can vary seasonally and with changes in subsurface conditions between boring locations. It should be noted that groundwater levels tend to fluctuate during periods of prolonged drought and extended rainfall and may be affected by man-made influences. The estimated seasonal high groundwater levels shown adjacent to the boring profiles are based on review of USDA/NRCS information and experience with similar soil conditions.

NADIC Project No.: PR.GEO-RD19013 Page 11 of 25

4.4 Sinkhole Risk

Based on the subsurface conditions encountered and NADIC's sinkhole experience, the proposed bridge area is considered a relatively high risk sinkhole area. This conclusion is based on the results of our field exploration, including the following:

A total loss of drilling fluid circulation was encountered in Borings EB-1B, IB-2A, IB-2B, IB-3A and EB-4B, at elevation ranging from +13 to -52 feet, NAVD-88.

The lack of stratigraphic continuity and consistency of the soil units.

Weight of hammer (WH) conditions were encountered in Borings IB-2A, IB-2B, IB-3A and IB-3B at elevations ranging from +83 to +7 feet, NAVD-88 Presence of buried organic muck indicating evidence of relic sinkhole conditions.

A separate field exploration was conducted to evaluate the sinkhole extent, followed by grouting remediation. These findings are provided in a separate report dated June 24, 2025.

5.0 LABORATORY TESTING

Representative soil samples were retained from the strata observed in each boring and returned to NADIC’s laboratory for visual classification and stratification in accordance with ASTM D 2487 “Standard Classification of Soils for Engineering Purposes” (Unified Soil Classification System).

Selected soil samples were tested to aid in classifying the soils and to help in evaluating the general engineering characteristics of the recovered soils. Laboratory classification tests consisted of the following: Percent passing no. 200 sieve, moisture content, organic content, Atterberg limits, unit weight determination, soils specific gravity and consolidation tests. The results of these tests are presented on Table 5 in Appendix A and on the Report of SPT borings in Appendix B.

Environmental corrosion tests (pH, resistivity, chloride content, and sulfate content) were also performed on selected samples from the SPT borings. Corrosion tests were performed in accordance with FDOT Structure Design Guidelines. The environmental classification for the substructures is presented on the Report of SPT borings in Appendix B and should be classified as follows:

EB-1A: Moderately aggressive for use of Steel and slightly aggressive for use of Concrete (Resistivity = 7,580 ohm/cm)

IB-2B: Moderately aggressive for use of Steel and slightly aggressive for use of Concrete

(Resistivity = 9,550 ohm/cm)

SW-2: Extremely aggressive for use of Steel and moderately aggressive for use of Concrete (Resistivity = 7,900 ohm/cm)

Wetland Water: Moderately aggressive for use of Steel and slightly aggressive for use of

Concrete (pH = 6.15)

NADIC Project No.: PR.GEO-RD19013 Page 12 of 25

Relatively undisturbed soil samples were obtained at Borings EB-1B and IB-2B and transported to our laboratory for extraction and classification. Once the samples were classified, a selected representative sample was prepared for consolidation testing, in general accordance with ASTM D2435. The consolidation testing was performed by Universal Engineering Sciences company.

The results of the consolidation tests and associated laboratory soil classification tests are presented below:

Boring No.

Approx.

Station &

Offset

Void Ratio

Unit Weight (lb/ft3)

Cc 1 Cr

Pc

(lb/ft2)

Specific Gravity

Unified Soil Classification

(USCS)

EB-1B

417+49, 2’ LT

3.47 50.5 2.06 0.17 1213 2.0 PT

IB-2B

418+51, 1’ LT

4.18* 17.9* 4.1* 0.18* 0.6* 1.5* PT

1.75 59.4 0.65 0.06 1755 2.7 CH

1Coefficient of Consolidation 2Coefficient of Reconsolidation 3Preconsolidation Pressure NP: Non-plastic *Results taken from GEC Muck Evaluation Report dated March 22, 2024

6.0 EVALUATION AND RECOMMENDATIONS

The following sections of this report present an overview of the preliminary analyses conducted to date.

6.1 Foundation Alternatives

Based on the results of our field study, the following foundation types were evaluated for this submittal:

1. Shallow Foundations

2. Drilled Shafts

3. Steel Piles

4. Prestressed Concrete Piles (PCP)

Presented below is a brief discussion of each of the foundation alternatives:

1. Shallow Foundations

Shallow footings are not considered a technically feasible alternative for the bridge foundations because of limited space for relatively large foundation sizes and limited working space expected adjacent to travel lane, and likely presence of buried utilities within proposed foundation locations. The design and construction of shallow foundations may be difficult.

Based on the information provided above, we do not recommend shallow foundations as a viable foundation alternative to support large bridge footings in these conditions.

NADIC Project No.: PR.GEO-RD19013 Page 13 of 25

2. Drilled Shafts

Drilled shafts are not considered a practical foundation alternative for the project because drilled shaft foundations are unlikely to be cost effective when compared to driven pile foundations due to the anticipated difficult construction.

3. Precast Prestressed Concrete Piles (PCP)

Driven square prestressed concrete piles are considered a feasible foundation system. PCP is readily available and generally has a lower cost per ton than other pile types. Estimated Davisson Capacity Curves for 24-inch PCP are presented on Plates 1 through 4 in Appendix C. Estimated Davisson Capacity Curves for 18-inch PCP are presented on Plates 5 through 8 in Appendix D. FB-Deep computer outputs for 24-inch and 18- inch PCP piles are included in Appendix D.

4. Steel Piles

Steel pile types including pipe and HP piles are feasible foundation alternatives; however, they are not the most cost-effective foundation alternative due to the relatively high cost per ton of capacity in comparison to other foundation alternatives. The steel piles do not develop as much capacity for similar penetration depths as square concrete piles. As presented in this report, subsurface conditions at the proposed bridge sites are considered moderately aggressive for steel. Due to corrosivity of steel and its impact on the environment, steel piles are not considered a viable foundation alternative. However, estimated Davisson Capacity Curves for 24-inch Steel Pipe Piles are presented on Plates 9 through 12 in Appendix D. FB- Deep computer outputs for 24-inch Steel Pipe Piles are included in Appendix D.

6.2 Selected Foundation System

It is understood that 24-inch square precast prestressed concrete piles (PCP) have been selected as the preferred foundation system to support the proposed Reams Road Bridge based on information provided by TLP. The proposed bridge designs will be by the Load and Resistance Factor Design (LRFD) code. Presented below is a discussion on design considerations and recommendations for 24-inch PCP.

6.3 Axial Capacity for Piles

Axial pile capacity analyses were performed for 24-inch PCP using the FDOT computer FB-Deep Version 3.1.0 based on FDOT Research Bulletin RB-121. The results of these analyses presented in the form of Estimated Davisson Capacity Curves are presented on Plates 1 through 4 in Appendix C.

Additionally, axial pile capacity analyses were performed for 18-inch PCP and Steel Pipe Piles, and the results are presented on Plates 5 through 12 in Appendix D.

NADIC Project No.: PR.GEO-RD19013 Page 14 of 25

The Estimated Davisson Capacity represents the theoretical failure capacity of a driven pile based on deflection criteria generated from static load testing. The Estimated Davisson Capacity of a single pile as computed by the FB-Deep program is as follows:

Estimated Davisson Capacity = Ultimate Skin Friction + Mobilized End Bearing

Where, mobilized end bearing is 1/3 of the ultimate end bearing as defined by the RB- 121 report.

The Davisson Design Capacity Curves shown on Plates 1 through 4 in Appendix C can be used to find the approximate tip elevations and estimate pile lengths using the following formula:

Nominal Bearing Resistance (NBR) ≥ (Factored Design Load + Net Scour + Downdrag)/

Where is a resistance factor and if Driven Piles with ≥ 5% Dynamic Testing:

• = 0.75 for Driving Criteria based on Dynamic Testing and Analysis &

Static Load Test

• = 0.65 for Driving Criteria based Dynamic Testing and its Analysis

Where is a resistance factor and if Driven Piles with 100% Dynamic Testing:

• = 0.85 for Driving Criteria based on Dynamic Testing and Analysis &

Static Load Test

• = 0.75 for Driving Criteria based Dynamic Testing and its Analysis

6.4 Estimated Pile Tip Elevation

It is our understanding that the bridge will be constructed in two (2) phases, initially on the north side of Reams Road, followed by the south side, to allow for continued traffic access during construction.

Based on this phasing information, the factored design loads provided by TLP, the results of the SPT borings and our FB-Deep analyses, the anticipated pile tip elevations for the proposed bridge are summarized below on Tables 6A and 6B. The NBR was calculated with a factor of 0.65, a resistance factor driven criteria for Driving Criteria based on ≥ 5% Dynamic Testing and its analysis.

NADIC Project No.: PR.GEO-RD19013 Page 15 of 25

Table 6A Estimated Pile Tip Elevation and Pile Length: North Bridge

Bent

Boring No.

Pile Size (inch)

Factored Design Load

(Tons)

Net Scour Resistance

(Tons)

Downdrag (Tons)

NBR*

(Tons)

Pile Cutoff

Elev. (ft, NAVD-88)

Anticipated Pile Tip Elev. (ft, NAVD-88)

Est. Pile Length**

(ft)

Est. Test Pile

Length (ft)

End Bent 1 EB-1A 24 172 N/A 107 429 102.5 +19 83.5 98.5

Int. Bent 2 IB-2A 24 258 N/A N/A 397 103.2 -16 119.2 134.2

Int. Bent 3 IB-3A 24 258 N/A N/A 397 102.2 -9 111.2 126.2

End Bent 4 EB-4A 24 172 N/A N/A 265 99.6 +48 51.6 66.6

*NBR = Nominal Bearing Resistance = Design Load + Net Scour + Downdrag Φ Where Φ = 0.65 **Pile length is based on the cutoff elevation

Table 6B Estimated Pile Tip Elevation and Pile Length: South Bridge

Bent

Boring No.

Pile Size (inch)

Factored Design Load

(Tons)

Net Scour Resistance

(Tons)

Downdrag (Tons)

NBR*

(Tons)

Pile Cutoff

Elev. (ft, NAVD-88)

Anticipated Pile Tip Elev. (ft, NAVD-88)

Est. Pile Length**

(ft)

Est. Test Pile

Length (ft)

End Bent 1 EB-1B 24 172 N/A 95 411 102.5 +19 83.5 98.5

Int. Bent 2 IB-2B 24 258 N/A N/A 397 103.2 +1 102.2 117.2

Int. Bent 3 IB-3B 24 258 N/A N/A 397 102.2 +1 101.2 116.2

End Bent 4 EB-4B 24 172 N/A N/A 265 99.6 +49 50.6 65.5

*NBR = Nominal Bearing Resistance = Design Load + Net Scour + Downdrag

Where Φ = 0.65 **Pile length is based on the cutoff elevation

The FB-Deep results are based on long-term axial capacity derived after dissipation of soil pore water pressures; therefore, skin friction capacity may take several days after end of pile drive to get to full capacity. Because of this phenomenon, the actual pile tip elevations required to attain the NBR during driving could be deeper than the estimated pile tip elevations shown above. In addition, due to the type of soils encountered, it is expected that end bearing will not be a significant portion of the total axial capacity. Therefore, set-checks and/or re-drives should be anticipated during production pile installation to gain additional skin friction capacity.

NADIC Project No.: PR.GEO-RD19013 Page 16 of 25

Depths and capacities recommended herein are for individual piles. No reduction of the individual pile capacities will be required if piles are spaced center-to-center at three (3) times their width or greater. We recommend a test pile program to be conducted to verify driving conditions and refine estimates of pile length. The test piles should be instrumented with the Pile Driving Analyzer (PDA) in accordance with FDOT Specification 455.

6.5 Downdrag Considerations/Embankment Settlement

It is anticipated that embankment fill will be placed at proposed Ream Road Bridge beginning and end of the bridge locations. The embankment fill height is estimated to be about 16 feet above the existing ground surface. The abutment piles are anticipated to be driven prior to construction of the proprietary retaining wall system. Therefore, settlement caused by the fill loads could generate downdrag loads on the piles.

The encountered near surface soil is composed primarily of loose to very dense sandy soils, placement of any embankment fill on these granular cohesionless soils will result in immediate settlement which will essentially cease as the fill placement is completed. Clayey soils and weight of hammer conditions were encountered at elevation range between +91 and +9 feet NAVD-88.

We anticipate both elastic and consolidation settlements to occur. Long term consolidation settlement can result to pile downdrag. Downdrag loads, often referred to as negative skin friction, are induced on foundation elements due to consolidation of foundation soils under fill loads.

Downdrag loads are more pronounced if piles are driven prior to embankment fill construction on compressible soils.

Near surface muck was encountered at elevation range between +95 and +86 feet NAVD-88, and buried muck was encountered at elevation between +11 and +15 feet NAVD-88. Near surface muck at the bridge end bents shall be excavated and replaced with clean sands to avoid excessive consolidation settlement and downdrag loads.

Settlement analyses were conducted using Settle3 software, and the results are summarized in the following Tables 7A and 7B and presented in Appendix E. The analyses were performed assuming removal of the near surface muck.

Table 7A Summarized Settlement Analysis: North Bridge

Bent No. Boring No.

Total Estimated

Settlement (inches)

Total Estimated Elastic Settlement

(inches)

Total Estimated Consolidation

Settlement (inches)

End Bent 1 EB-1A 5.2 0.9 4.3 End Bent 4 EB-5A 0.7 0.5 0.2

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Table 7B Summarized Settlement Analysis: South Bridge

Bent No. Boring No.

Total Estimated

Settlement (inches)

Total Estimated Elastic Settlement

(inches)

Total Estimated Consolidation

Settlement (inches)

End Bent 1 EB-1B 5.1 0.8 4.3 End Bent 4 EB-5B 0.7 0.5 0.2

Due to granular nature of the surficial soil, it is anticipated that about one (1) inch of the estimated settlements will occur concurrently with embankment construction. The rate of consolidation of the encountered clayey soils will however be slower than the granular soil encountered. Based on the anticipated consolidation settlements, embankment construction at the End Bent 1 location may be addressed either by surcharging to pre-settle the clayey soils prior to construction of retaining walls and bridge foundations, or by reducing downdrag through increasing the capacity of the piles by extending pile lengths. The approach selected and presented in this report is the reduction of downdrag by extending pile lengths at End Bent 1 location, as summarized in Tables 6 and 9.

Downdrag loads were evaluated by using the Neutral Plane (NP) Method. The NP Method for downdrag uses a graphical plot to identify the location where downward drag forces (negative skin friction) are balanced by upward supporting forces (positive skin friction and tip resistance). The load curve represents the sustained service structural load plus the accumulating negative skin friction, and the resistance curve represents the mobilized positive skin friction and tip resistance.

Based on the downdrag analysis, it is anticipated that the following downdrag forces of 90 to 108 Tons would occur at the End Bents. These values are included in the Pile Data Tables. Downdrag calculations are presented in Appendix E.

6.6 Lateral Load Consideration

It is understood that lateral analysis will be performed by the structural engineer. FL-Pier soil input parameters presented in Table 8 in Appendix A have been provided to the structural engineer to aid in design.

6.7 Pile Group Action

No reduction of the individual pile capacities will be required if piles are spaced center-to-center at 3 times their width or greater. The end bent pile caps usually contribute to the overall bearing capacity of the pile group, provided they are supported on competent soil outside the outer perimeter of the group. However, we do not recommend taking credit for this additional capacity.

DRMP January 21, 2026

NADIC Project No.: PR.GEO-RD19013 Page 18 of 25

6.8 Pile Settlement

Settlement of pile supported bridge piers should be small and tolerable for a typical single row pile group. For the typical loads expected for this project, individual maximum pile head settlements are estimated to be in the order of ½ inch.

6.9 Test Pile Program

We recommend a test pile program be conducted to verify driving conditions and refine estimates of pile length. For planning programs, we recommend four test piles be installed: one per pier. The recommended test pile number and lengths are shown in Tables 9A and 9B, the Pile Data Table.

During test pile driving, we recommend the test piles be dynamically monitored with the Pile Driver Analyzer (PDA) or its equivalent to assess pile bearing capacity.

DRMP January 21, 2026

NADIC Project No.: PR.GEO-RD19013 Page 19 of 25

Table 9A Pile Data Table: North Bridge

ISTALLATION CRITERIA DESIGN CRITERIA

LOCATION

PILE

SIZE

(INCH)

NOMINAL

BEARING

RESISTANCE

(TONS)*

NOMINAL

UPLIFT

RESISTANCE

(TONS)

MIN.

TIP

ELEV.

(FT)

TEST PILE REQ’D

JET

ELEV.

(FT)

REQ’D

PREFORM

ELEV. (FT)

FACTORED

DESIGN

LOAD

(TONS)

DOWN

DRAG

(TONS)

TOTAL

SCOUR

RESIST

(TONS)

NET

SCOUR

RESIST

(TONS)

100 YR

SCOUR

ELEV.

(FT)

LONG

TERM

SCOUR

ELEV.

(FT)

NUMBER

LENGTH

(FT)***

End Bent 1 24 429 N/A 19 1 98.5 N/A N/A 172 107 N/A N/A N/A N/A 0.65

Int. Bent 2 24 397 N/A -16 1 134.2 N/A N/A 258 N/A N/A N/A N/A N/A 0.65

Int. Bent 3 24 397 N/A -9 1 126.2 N/A N/A 258 N/A N/A N/A N/A N/A 0.65

End Bent 4 24 265 N/A 48 1 66.6 N/A N/A 172 N/A N/A N/A N/A N/A 0.65

Table 9A

Pile Data Table: South Bridge

ISTALLATION CRITERIA DESIGN CRITERIA

LOCATION

PILE

SIZE

(INCH)

NOMINAL

BEARING

RESISTANCE

(TONS)*

NOMINAL

UPLIFT

RESISTANCE

(TONS)

MIN.

TIP

ELEV.

(FT)

TEST PILE REQ’D

JET

ELEV.

(FT)

REQ’D

PREFORM

ELEV. (FT)

FACTORED

DESIGN

LOAD

(TONS)

DOWN

DRAG

(TONS)

TOTAL

SCOUR

RESIST

(TONS)

NET

SCOUR

RESIST

(TONS)

100 YR

SCOUR

ELEV.

(FT)

LONG

TERM

SCOUR

ELEV.

(FT)

NUMBER

LENGTH

(FT)***

End Bent 1 24 411 N/A 19 1 98.5 N/A N/A 172 95 N/A N/A N/A N/A 0.65

Int. Bent 2 24 397 N/A 1 1 117.2 N/A N/A 258 N/A N/A N/A N/A N/A 0.65

Int. Bent 3 24 397 N/A 1 1 116.2 N/A N/A 258 N/A N/A N/A N/A N/A 0.65

End Bent 4 24 265 N/A 49 1 65.6 N/A N/A 172 N/A N/A N/A N/A N/A 0.65

* Nominal Bearing Resistance = Design Load + Net Scour + Downdrag

**Minimum Tip Elevation shall be determined in accordance with Section 455-5.8.

The contractor shall verify the locations of all utilities prior to any pile driving.

All test piles are to be dynamically monitored using the Pile Driving Analyzer or an approved equivalent.

*** Splicing will be required for all 24-inch pile lengths greater than 140 feet.

NADIC Project No.: PR.GEO-RD19013 Page 20 of 25

6.10 Protection of Existing Structures

We are of the opinion that the selected 24-inch PCP could be driven without significant structural distress on nearby structures and buildings. However, we recommend that both pre and post construction condition survey and vibration monitoring of any structure within 150 feet of the bridge be performed. The survey and vibration monitoring procedures shall meet the requirements of Section 455-1.1 of FDOT Standard Specifications.

6.11 Proprietary Walls – Bridge Abutments

The abutment of the proposed bridge will consist of approximately 16-foot fill soils retained by vertical proprietary walls; Mechanically Stabilized Earth (MSE) walls. While typical fill soils exhibit higher strength properties, FDOT specifications currently permit the use of a maximum angle of internal friction of 30 degrees and unit weight of 105 pcf for design proprietary wall systems. It is our understanding that temporary MSE walls will be installed during construction and removed as the construction phases progress.

To estimate soil reinforcement strap lengths, we analyzed the proposed walls for external stability, sliding resistance, overturning and bearing capacity. We understand the proprietary wall supplier will be responsible for the internal stability of the wall systems. Our analysis did not consider potential failure surfaces which intersect reinforcement layers as this would be considered an internal stability failure.

The reinforcement lengths are recommended for various wall heights to achieve the recommended Capacity-Demand Ratio (CDR) overturning, eccentricity, sliding and bearing resistance as well as overall global stability. The recommended CDR and factor of safety for selection of minimum strap heights are as follows:

Overturning ≥1.0 Eccentricity ≤1.0 Sliding ≥1.0 Bearing Resistance ≥1.0 Global ≥1.5

Global or rotational slope stability analysis was performed using STEDwin2.90, a slope stability program developed by Purdue University, and generally used in Florida Department of Transportation (FDOT) and other transportation projects. The result of our stability analysis indicates a minimum factor of safety of 1.5. The Florida Department of Transportation program LRFD External Stability Analysis was used to evaluate overturning eccentricity, sliding and bearing resistance. The results presented herein are based on a maximum MSE wall height of 16 feet. Note the factored bearing resistance includes the foot embedment term. Results from our analysis and minimum soil reinforcement lengths for permanent and temporary MSE walls are shown below on Tables 10A through 10C, and in Appendix E.

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Table 10A Minimum Soil Reinforcement Lengths and Bearing Capacity: North MSE Walls

North MSE Wall No. 1

Wall Height (ft) <=8 10 12 14 16 Reinforcement Lenth (ft) 7 8 9 10 12 Overturning 2.3 2.1 2.0 2.3 2.2 Eccentricity 0.9 1.0 1.0 0.9 0.9 Sliding 1.1 1.1 1.1 1.2 1.2 Bearing Resistance 1.8 1.5 1.3 1.4 1.3 Factored Bearing Resistance (psf) 4,502 4,651 4,810 5,426 5,589

North MSE Wall No. 2

Wall Height (ft) <=8 10 12 14 16 Reinforcement Lenth (ft) 7 8 9 10 12 Overturning 2.3 2.1 2.0 2.3 2.2 Eccentricity 0.9 1.0 1.0 0.9 0.9 Sliding 1.1 1.1 1.1 1.2 1.2 Bearing Resistance 1.8 1.5 1.3 1.4 1.3 Factored Bearing Resistance (psf) 4,502 4,651 4,810 5,426 5,589

Table 10B

Minimum Soil Reinforcement Lengths and Bearing Capacity: South MSE Walls

South MSE Wall No. 1

Wall Height (ft) <=8 10 12 14 16 Reinforcement Lenth (ft) 7 8 9 10 12 Overturning 2.3 2.1 2.0 2.3 2.2 Eccentricity 0.9 1.0 1.0 0.9 0.9 Sliding 1.1 1.1 1.1 1.2 1.2 Bearing Resistance 1.8 1.5 1.3 1.4 1.3 Factored Bearing Resistance (psf) 4,502 4,651 4,810 5,426 5,589

South MSE Wall No. 2

Wall Height (ft) <=8 10 12 14 16 Reinforcement Lenth (ft) 7 8 9 10 12 Overturning 2.3 2.1 2.0 2.3 2.2 Eccentricity 0.9 1.0 1.0 0.9 0.9 Sliding 1.1 1.1 1.1 1.2 1.2 Bearing Resistance 1.8 1.5 1.3 1.4 1.3 Factored Bearing Resistance (psf) 4,502 4,651 4,810 5,426 5,589

NADIC…