UT_FLAP_3108(1)_Final_Pavement_Report.pdf

Pavement Design Report Cascade Scenic Drive and Cascade Springs Road

Wasatch County, Utah

January 11, 2018

Submitted To:

CH2M

322 E. Front Street Suite 200

Boise, ID 83702

By:

Shannon & Wilson, Inc.

1321 Bannock Street, Ste. 200 Denver, CO 80204

23-1-01373-109

1321 BANNOCK STREET, SUITE 200

DENVER, COLORADO 80204-4077

303-825-3800 FAX: 303-825-3801

TDD 1-800-833-6388

www.shannonwilson.com 23-1-01373-109

January 11, 2018

CH2M

322 E. Front Street, Suite 200 Boise, ID 83702

Attn: Mr. Blaise Exon, PE

RE: PAVEMENT DESIGN REPORT, CASCADE SCENIC DRIVE AND CASCADE

SPRINGS ROAD, WASATCH COUNTY, UTAH

We are pleased to submit our pavement design report for the above-referenced project. The enclosed report summarizes subsurface conditions encountered in a subsurface exploration program and provided our pavement design recommendations for the proposed project.

We appreciate the opportunity to be of service to you on this project. If you have any questions or require further information, please contact me at 303-825-3800.

Sincerely, SHANNON & WILSON, INC.

Mark Vessely Vice President

KDD:DAA/kdd

Encl: Geotechnical Design Report

23-1-01373-109-L1/wp/ksm

23-1-01373-109-R2.docx/wp/ 23-1-01373-109 i

TABLE OF CONTENTS

Page

1.0 INTRODUCTION

2.0 SCOPE OF WORK

3.0 SITE AND PROJECT DESCRIPTION

4.0 FIELD EXPLORATIONS AND LABORATORY TEST RESULTS

5.0 SUBSURFACE CONDITIONS

5.1 Subsurface Conditions

5.2 Groundwater

6.0 PAVEMENT DESIGN RECOMMENDATIONS

6.1 Traffic Loading

6.2 Design Subgrade Resilient Modulus

6.3 Full Depth Reclamation (FDR)

6.4 Recommended Pavement Sections

7.0 CONSTRUCTION AND MATERIALS SPECIFICATIONS

7.1 Pavement Materials

7.2 Earthwork and Grading

7.2.1 Subgrade Preparation and Proof Rolling

7.2.2 Fill Placement and Compaction

8.0 CONSTRUCTION OBSERVATION

9.0 CLOSURE

10.0 REFERENCES

TABLE OF CONTENTS (cont.)

ii

TABLES

1 PDDM Flexible Pavement Design Parameters 2 Recommended Paving Materials

FIGURES

1 Site and Exploration Plan (6 Sheets) 2 Variation of Pavement Subgrade Soils

APPENDIX

A Pavement Design Calculations

FINAL PAVEMENT DESIGN REPORT

CASCADE SCENIC DRIVE AND CASCADE SPRINGS ROAD

WASATCH COUNTY, UTAH

1.0 INTRODUCTION

This report presents our pavement recommendations for the proposed roadway improvements associated with the Central Federal Lands Highway Division (CFLHD) subject project Cascade Springs Road, UT FLAP 3108(1) and Cascade Scenic Drive Design (NFSR #70114) near Heber City in Wasatch County, Utah. The Cascade Springs Road Project (Phase 1) consists of paving

5.1 miles of Cascade Springs Road, and the Cascade Scenic Drive Project (Phase 2) consists of repaving approximately 7 miles of roadway. This report summarizes our subsurface explorations and laboratory testing, and presents recommendations for design and construction of the pavement features based on 70 percent design plans provided by CH2M. Geotechnical engineering recommendations will be presented in a separate Geotechnical Design Report (Shannon & Wilson, 2017).

This pavement design report should not be used without our approval if any of the following occurs:

Assumptions stated in this report have changed, Project details change or new information becomes available such that our recommendations may be affected, and

More than five years has passed since the date of this report.

If any of these occur, we should be retained to review the applicability of our recommendations.

2.0 SCOPE OF WORK

Our services were conducted in general accordance with our Purchase Order No. 101000097 with CH2M, dated September 5, 2017 and the CFLHD Scope of Work for Task Order Number DTFH68-16-D-00007, dated September 1, 2017. We completed the following tasks for the project to complete our pavement analysis.

Coordinated subcontractors and traffic control for drilling borings.

Observed, logged, and collected soil and rock samples from 55 auger and rock core borings along Cascade Springs Road.

23-1-01373-109-R2.docx 23-1-01373-109

Observed, logged, and collected soil and rock samples from 20 auger borings along Cascade Scenic Drive.

Completed laboratory testing on selected soil samples from the borings.

Evaluated geotechnical data and completed pavement design.

Prepared this pavement design report.

Our scope of services did not include performing a traffic study, or evaluating the presence or absence of hazardous or toxic materials in the soil, surface water, groundwater, or air, on or below or around this site. If such contamination exists, it would not be possible to determine it within this limited scope of work.

3.0 SITE AND PROJECT DESCRIPTION

Both the Phase 1 and 2 Projects are located in the Uintah National Forest, approximately 2 miles west of Midway, Utah. The eastern extent of Phase 1 begins at the Wasatch Mountain State Park limits (the terminus of State Route [SR] 220) and extends about 5.1 miles southwest to the Cascade Springs parking located at the junction of FR-475 (Little Deer Creek Road) and FR-114.

Phase 2 then continues southwest for approximately 6.8 miles until the junction of SR 92.

The existing topography of both the Phase 1 and 2 Projects are mountainous with steep grade changes on either side of the roadway. The Cascade Springs Road currently varies in width from 23 to 31 feet and generally consists of two lanes (a single lane in each direction). Sections of the Phase 1 roadway will be realigned using cuts, fills, and walls. To meet the recommended travel way in Wasatch County, this portion of Phase 1 is being designed with a 22-foot paved width, 1-foot gravel shoulders, and a 3-foot graded ditch.

Currently, the western extent of Phase 1 (approximately 0.72 miles) is paved with a full-depth hot asphalt concrete pavement (HACP) placed directly on the roadway subgrade. The condition of the pavement is highly deteriorated with numerous potholes and occasional asphalt patches.

The age of the existing asphalt is unknown. The remaining portion of the roadway is surfaced with aggregate. At the time of our explorations, the thickness of the aggregate surfacing varied typically between 4 and 6 inches and has several areas of ‘washboard’-like rutting of the aggregate surfacing.

We understand the Phase 2 roadway is currently paved with HACP and the asphalt paved width varies from 24 to 30 feet and consists of two lanes (a single lane in each direction). The planned road width is 24 feet with two 12-foot travel widths. The Phase 2 roadway is planned for pavement rehabilitation by pulverizing the existing asphalt with the underlying base course and paving with a new asphalt surfacing (full depth reclamation [FDR]). Improvements included as part of the pavement rehabilitation include minor stabilization of shoulders using deep patch or subgrade excavation in localized areas.

4.0 FIELD EXPLORATIONS AND LABORATORY TEST RESULTS

Shannon & Wilson conducted a subsurface exploration program for the Phase 1 alignment on October 24 through 28, 2016 and December 5 through 7, 2017. The subsurface exploration program consisted of drilling and sampling 55 borings, designated SW-P-01 through SW-P-26, SW-C-01 through SW-C-06, SW-B-01, SW-B-02, and SW-B-04 through SW-B-13, and SW-W- 01 through SW-W-11. On October 3 and 4, 2017, a subsurface exploration program was completed along Phase 2. This program consisted of drilling and sampling 20 borings for pavement design designated SW-P2-01 through SW-P2-20. The locations of the borings are shown on Figure 1. Geotechnical laboratory tests were completed on select samples retrieved from the borings to estimate soil index and engineering properties. The logs and laboratory test data from our geotechnical investigation are not reproduced herein for the sake of brevity, but instead are located in our geotechnical report for this project (Shannon & Wilson, 2017).

5.0 SUBSURFACE CONDITIONS

For purposes of our pavement analyses, it was necessary for us to assume that the results of the explorations and testing are representative of conditions throughout the project site. However, as discussed below, subsurface conditions should be expected to vary. Unanticipated soil conditions are commonly encountered and cannot be fully determined by a limited boring and testing program. Such unexpected conditions frequently require that additional expenditures be made to attain a properly constructed project. Therefore, some contingency fund is recommended to accommodate such potential extra costs.

5.1 Subsurface Conditions

For the purposes of this report, subsurface conditions for the surficial soils/rock (less than 6 feet) below proposed pavement will be discussed. Deeper subsurface conditions are discussed in the geotechnical design report (Shannon & Wilson, 2017). Based on the pavement and geotechnical borings, the observed pavement subgrade materials generally consist of clayey gravel with sand to clayey sand with gravel (generally AASHTO soil classification of A-6 in CSD and A-7-6 in

Phase 1). In addition, occasionally borings encountered shallow refusal from limestone rock with varying degrees of weathering. Between borings SW-P2-14 and SW-P2-17 in Phase 2 (approximately mile posts 9.8 and 9.2, respectively), we encountered granular soils with lower plasticity clay or silt fines in the roadway subgrade (A-2-4 and A-2-6 soils). Refer to Figure 2 for the variation of subgrade soils observed along alignment. Figure 2 contains the summary of the subgrade soil classification and R-value (Hveem stabilometer) test results. Individual laboratory test results are presented in our geotechnical report (Shannon & Wilson, 2017).

5.2 Groundwater

Groundwater was not encountered in the borings at the time of drilling; however, groundwater fluctuations are possible and likely depend on many factors, including seasonal variations, and local precipitation. We do not anticipate groundwater will influence design or construction of the project.

6.0 PAVEMENT DESIGN RECOMMENDATIONS

Our preliminary pavement design and results are based on the design procedures presented in the 1993 American Association of State Highway and Transportation Officials (AASHTO) Guide for the Design of Pavement Structures (AGDPS), with guidance from the U.S. Department of Transportation and Federal Highway Administration (FHWA) Federal Lands Highway Project Development and Design Manual (PDDM), dated March 2008. We understand the proposed improvements to Cascade Springs Drive will constitute a 4R project and pavements will be designed for a 25-year design life.

6.1 Traffic Loading

Performance of a pavement system depends on the pavement material and thicknesses, subgrade strength, traffic loads and repetitions, design life, and subgrade drainage characteristics. The road is understood to be primarily a forest access route that is typically closed from November to May. Based on discussions with CH2M, CFLHD, Forest Service, and Wasatch County we understand the anticipated roadway traffic volume is considered low and will primarily consist of relatively light vehicles; 85 percent or more passenger cars and pickup trucks with up to 15 percent of the traffic consisting of pickup trucks with recreational vehicle trailers. We do not anticipate either Phase 1 or 2 roads to be used as a trucking route.

Based on a traffic study by C2HM, the two-way 2018 average daily traffic (ADT) volume in Phase 1 is approximately 120 vehicles per day and the projected traffic loading increases to 200 vehicles per day by 2028. For Phase 2, the two-way 2018 ADT volume is 240 vehicles per day with a projected 2028 ADT of 370 vehicles per day. Each ADT incorporates the seasonal road closure. Using these current and the projected ADT values, we estimate the 25 year design life 18-kip equivalent single-axle loading [ESAL] values of approximately 24,000 and 26,000 for the Phase 1 and 2 roads, respectively. Refer to the ESAL calculation worksheet provided in Appendix. Based on guidance from the PDDM, the projected traffic loading does not meet the minimum ESAL value and we therefore used the PDDM minimum ESAL value of 50,000 in our pavement design analysis.

6.2 Design Subgrade Resilient Modulus

In accordance with PDDM design procedures, we analyzed the pavements using the mean R-value test results values of 19 and 14 percent, respectively, for the Phase 1 and 2 roadways.

For Phase 2, we omitted the R-value test results from boring SW-P2-14 as the subgrade conditions and resulting R-value are not consistent with majority of roadway alignment. We then used an R-value to a resilient modulus value correlation presented in the AGDPS. For our analysis, we assumed a resilient modulus value of approximately 7,800 and 6,000 pounds per square inch, respectively, for the Phase 1 and 2 Projects.

6.3 Full Depth Reclamation (FDR)

We understand that pulverized FDR is being considered for the paved portions of both Phases 1 and 2. For an unstabilized FDR layer, the process involves pulverizing and mixing the existing HACP with imported aggregate, as necessary, to create a uniformly blended, homogeneous material that will be incorporated into the proposed pavement section as a base layer. Based on our experience, pulverizing the existing asphalt will likely result in mixing the existing bituminous surfacing into underlying base course (presumably old roadway aggregate surfacing).

Based on our subsurface explorations, the existing pavement sections generally consist of:

Cascade Springs Road (Phase 1): HACP thickness ranges from 1.0 to 6.0 inches with an average thickness of 3.4 inches. No base course material was observed below the HACP.

Cascade Scenic Drive (Phase 2): HACP thickness ranges from 3.0 to 6.5 inches with an average thickness of 4.5 inches. The base course thickness ranges from 5 to 14 inches with an average thickness of 6.8 inches

For our analysis, we assumed the FDR will be at least 4 inches thick for Phase 1 roadway and the combined base and asphalt thickness in Phase 2 roadway is approximately 8 inches thick. For Phase 1, due to the potential of mixing of cohesive fines in the FDR process, we assumed a drainage coefficient of 0.8.

6.4 Recommended Pavement Sections

The following table summarizes design parameters used in the preliminary flexible pavement analysis. The enclosed Flexible Pavement Design Worksheet provides additional design information.

TABLE 1

PDDM FLEXIBLE PAVEMENT DESIGN PARAMETERS

Design Parameter Design Value Pavement Design Life 25 years

Subgrade Resilient Modulus, MR Phase 1 Design R-value of 19% 7,800 psi Phase 2, Design R-value of 14% 6,000 psi

Reliability, R 75% Standard Normal Deviate, ZR (per AGDPS Table 4.1) -0.674 Serviceability Loss, ∆PSI (P0 of 4.2 to Pt of 2.0) 2.2 Overall Deviation, So 0.49 Structural Layer Coefficient for Hot Asphalt Concrete Pavement (HACP) 0.44 Untreated Base Course UTBC 0.12 Structural Layer Coefficient for Pulverized Full Depth Reclamation (FDR) 0.10 Drainage Coefficient of Phase 1 FDR 1.0 Drainage Coefficient of Phase 2 FDR 0.8 psi = pounds per square inch % = percent

Using the above parameters, we recommend the following preliminary pavement sections for consideration:

Cascade Springs Road (Phase 1):

3.0 inches of HACP overlying 6.0 inches of UTBC

3.0 inches of HACP overlying 4.0 inches of UTBC over 4.0 inches of Pulverized FDR

Cascade Scenic Drive (Phase 2):

3.0 inches of HACP overlying 7.0 inches of UTBC

3.0 inches of HACP overlying 8.0 inches of Pulverized FDR

7.0 CONSTRUCTION AND MATERIALS SPECIFICATIONS

The applicability of the design recommendations provided in this report is contingent on good construction practice and adherence to the project specifications. Poor construction techniques may alter conditions from those on which our recommendations are based and result in poor performance. Our analyses assume that this project will be constructed according to FP-14 U.S.

Customary Units (USDOT and FHWA, 2014) standards. The following sections provide additional construction considerations for this project.

7.1 Pavement Materials

The following table summarizes our preliminary recommendations for material selection. All specification sections reference the Standard Specifications for Construction of Roads and Bridges on Federal Highway Projects (FP-14).

TABLE 2

RECOMMENDED PAVING MATERIALS

Material Specification Additional Requirements/Comments

UTBC Section 301 • Use Gradation C, D, or E (Section 703.05)

• R-value > 80

HACP Section 401

• Mix design must meet requirements for ESAL values less than 300,000

• Can use current UDOT certified mix

Pulverized FDR Section 304 • Minimum R-value of 70

• Compact according to Section 204.11

Binder - • Use Superpave PG 64-28 Binder UTBC = Untreated Base Course HACP = Hot Asphalt Concrete Pavement FDR = Full Depth Reclamation ESAL = Equivalent Single-Axle Loading UDOT = Utah Department of Transportation PG = Performance Grading

Our recommended pavement thicknesses require the use of the specific FP-14 specification identified in Table 2. If an alternate base course or asphalt specification from FP-14 is selected, pavement sections will need to be redesigned and the pavement thicknesses may increase.

7.2 Earthwork and Grading

Earthwork, including placement of fill and subgrade preparation, should conform to the requirements provided in the FP-14 and the recommendations provided in the following sections.

7.2.1 Subgrade Preparation and Proof Rolling

Because the existing roadway surfacing will be reused, we do not recommend scarifying and recompacting the existing roadway surfacing, but instead directly proof-rolling the existing roadway surfacing. Proof-rolls should be completed with a fully-loaded, tandem-axle, 10-yard dump truck or equivalent. Areas that are identified as being loose, soft, or yielding during proof-rolling should be compacted in place, removed and reconditioned, or replaced with Backfill Material conforming to FP-14 (Section 704.03). The subgrade backfill material should be compacted to dense and unyielding condition and to the requirements described in Section 7.2.2.

Care should be taken during proof-rolling and subgrade preparation to avoid disturbing subgrade soils and supporting soils that will remain in place, as they can rut and pump under repeated construction traffic. The final subgrade surface should be sloped to promote positive drainage and kept free of water at all times. Leaving the subgrade elevation high until final grading begins is a means to reduce the potential for disturbance to the final subgrade materials.

Additionally, subgrades should be protected from drying or wetting in excess of what is required to achieve the specified compaction requirements.

7.2.2 Fill Placement and Compaction

All fill material placed should consist of soil that is free of organics, contaminants, debris, rock fragments larger than 3 inches. In addition, fill material should be placed in horizontal lifts, with the loose lift thickness not to exceed 12 inches for heavy equipment compactors and 4 inches for hand-operated compactors and be compacted to a dense and unyielding condition. Thinner lifts may be required, depending on the contractor’s equipment.

Backfill compaction requirements should be in accordance with Section 204.11 of FP-14. Based on our laboratory testing and for preliminary planning purposes, we anticipate that compaction requirements would follow FP-14 204.11(c) but this should be confirmed during construction.

8.0 CONSTRUCTION OBSERVATION

Pavement design recommendations are developed from a limited number of explorations and tests. Therefore, recommendations may need to be adjusted in the field. To this end, we recommend that a construction observation and monitoring program be implemented for the

10.0 REFERENCES

American Association of State Highway and Transportation Officials (AASHTO), 1993, AASHTO Guide for Design of Pavement Structures: Washington, D.C., American Association of State Highway and Transportation Officials.

U.S. Department of Transportation (USDOT) and FHWA, 2008, Federal Lands Highway Project Development and Design Manual: U.S. Department of Transportation and Federal Highway Administration, available from http://flh.fhwa.dot.gov/resources/manuals/pddm/.

U.S. DOT and FHWA, 2014, Federal Standard Specifications for Construction of Roads and Bridges on Federal Highway Projects, FP-14 English Units: U.S. Department of Transportation and Federal Highway Administration, available from http://flh.fhwa.dot.gov/resources/pse/specs/.

Shannon & Wilson, Inc., 2017, Draft Final Geotechnical Design Report, Cascade Scenic Drive and Cascade Springs Road, Wasatch County, Utah, dated December 29.

http://flh.fhwa.dot.gov/resources/manuals/pddm/ http://flh.fhwa.dot.gov/resources/pse/specs/

SW-P2-01

SW-P2-02

SW-P2-03

SW-P2-04

SW-P2-05

SW-P2-06

SW-P2-07

Map adapted from aerial imagery provided by

Google Earth Pro, reproduced by permission granted by Google Earth ™ Mapping Service.

NOTE

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D a t e

L o g i n

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500 1000

Approximate Scale in Feet

SITE AND EXPLORATION PLAN

23-1-01373-109January 2018

Cascade Scenic Drive

Cascade Springs Road

Wasatch County ,Utah

Sheet 1 of 6

FIG. 1

Pavement Boring Designation and

Approximate Location

LEGEND

SW-P-01

Culvert Boring Designation and

Approximate Location

SW-C-01

Fill/Cut Wall Boring Designation and

Approximate Location

SW-B-01

M a t c h l i n e

S h e t

Approximate Mile

Marker Location

SW-P2-09

SW-P2-08

SW-P2-10

SW-P2-11

Map adapted from aerial imagery provided by

Google Earth Pro, reproduced by permission granted by Google Earth ™ Mapping Service.

NOTE

F i l e n a m e

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C

F L H

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H M

H I L L

C a s c a d e

S p r i D r a f t i n g F p a v e m e n t d t e g i n

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D M

MT

500 1000

Approximate Scale in Feet SITE AND EXPLORATION PLAN

23-1-01373-109

Cascade Scenic Drive

Cascade Springs Road

Wasatch County ,Utah

Sheet 2 of 6

FIG. 1

Pavement Boring Designation and

Approximate Location

LEGEND

SW-P-01

Culvert Boring Designation and

Approximate Location

SW-C-01

Fill/Cut Wall Boring Designation and

Approximate Location

SW-B-01

M a t c h l i n e

S h e e t

M a t c h l i n e

S h e e t

Approximate Mile

Marker Location

January 2018

SW-P2-12

SW-P2-13

SW-P2-14

SW-P2-15

SW-P2-16

SW-P2-17

580+00

Map adapted from aerial imagery provided by

Google Earth Pro, reproduced by permission granted by Google Earth ™ Mapping Service.

NOTE

F i l e n a m e

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D M

MT

500 1000

Approximate Scale in Feet SITE AND EXPLORATION PLAN

23-1-01373-109

Cascade Scenic Drive

Cascade Springs Road

Wasatch County ,Utah

Sheet 3 of 6

FIG. 1

Pavement Boring Designation and

Approximate Location

LEGEND

SW-P-01

Culvert Boring Designation and

Approximate Location

SW-C-01

Fill/Cut Wall Boring Designation and

Approximate Location

SW-B-01

M a t c h l i e e t

M a t c h l i n e

S h e e t

Approximate Mile

Marker Location

SW-P2-18

SW-P2-19

SW-P2-20

SW-P-25

SW-C-06

SW-P-24

SW-P-23

SW-C-05

SW-B-10

SW-P-22

SW-B-09

SW-B-08

SW-B-13

SW-P-21

SW-B-12

SW-C-04

SW-P-20

SW-B-07

Approximate End of

Phase 2 / Beginning of

Phase 1

100+00

SW-P-26

Map adapted from aerial imagery provided by

Google Earth Pro, reproduced by permission granted by Google Earth ™ Mapping Service.

NOTE

F i l e n a m e

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MT

500 1000

Approximate Scale in Feet SITE AND EXPLORATION PLAN

23-1-01373-109

Cascade Scenic Drive

Cascade Springs Road

Wasatch County ,Utah

Sheet 4 of 6

FIG. 1

Pavement Boring Designation and

Approximate Location

LEGEND

SW-P-01

Culvert Boring Designation and

Approximate Location

SW-C-01

Fill/Cut Wall Boring Designation and

Approximate Location

SW-B-01

M a t c h l i n e

S h e e t

M a t c h l i e e t

C a s c a d p r i n s

R a d

Approximate Mile

Marker Location

SW-P-19

SW-B-06

SW-B-11

SW-P-18

SW-B-04

SW-P-17

SW-C-03

SW-P-16

SW-P-15

SW-B-05

SW-P-14 SW-B-02

SW-P-13

SW-P-12

SW-B-03

SW-P-11

D e c k r

SW-W-07

SW-W-08

SW-W-06

SW-W-05

SW-W-10

SW-W-09

SW-W-02

SW-W-01

SW-W-03

SW-W-04

Map adapted from aerial imagery provided by

Google Earth Pro, reproduced by permission granted by Google Earth ™ Mapping Service.

NOTE

F i l e n a m e

I E

F

D

E N s

C

F L H

D

C

H M

H I L L

C a s c a d e

S p r i D r a f t i n g F p a v e m e n t d t e g i n d a a

MT

500 1000

Approximate Scale in Feet SITE AND EXPLORATION PLAN

23-1-01373-109

Cascade Scenic Drive

Cascade Springs Road

Wasatch County ,Utah

Sheet 5 of 6

FIG. 1

Pavement Boring Designation and

Approximate Location

LEGEND

SW-P-01

Culvert Boring Designation and

Approximate Location

SW-C-01

Fill/Cut Wall Boring Designation and

Approximate Location

SW-B-01

M a t c h l i e e t

M a t c h l i n e

S h e e t

C a s c a d e

S p r i n g s

R o a d

Approximate Mile

Marker Location

SW-P-11

SW-P-10

SW-C-02

SW-P-09

SW-P-08

SW-P-07

SW-P-06

SW-B-01

SW-P-05

SW-P-04

SW-C-01

SW-P-03

SW-P-02

SW-P-01

SW-W-11

Map adapted from aerial imagery provided by

Google Earth Pro, reproduced by permission granted by Google Earth ™ Mapping Service.

NOTE

F i l e n a m e

I E

F

D

E N s

C

F L H

D

C

H M

H I L L

C a s c a d e

S p r i D r a f t i n g F p a v e m e n t d t e g i n d a a

MT

500 1000

Approximate Scale in Feet SITE AND EXPLORATION PLAN

23-1-01373-109

Cascade Scenic Drive

Cascade Springs Road

Wasatch County ,Utah

Sheet 6 of 6

FIG. 1

Pavement Boring Designation and

Approximate Location

LEGEND

SW-P-01

Culvert Boring Designation and

Approximate Location

SW-C-01

Fill/Cut Wall Boring Designation and

Approximate Location

SW-B-01

M a t c h l i n e

S h e e t

C a s c a p r i n s a d

Approximate Mile

Marker Location

1.

2.

Notes:

The design R-value is the mean of the low-bound data per roadway segment (i.e., excluding the results from boring SW-P2-14).

Project stationing changes approximately at MP 6.89 where Sta.740+36 is equal to Sta. 82+66.

SW

-P

-0

SW

-P

-0

SW

-P

-1

SW

-P

-1

SW

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-1

SW

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-2

SW

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2-

SW

-P

2-

SW

-P

2-

SW

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2-

SW

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2-

[8] [16]

[26]

[21] [24][16]

[10] [8]

[16]

[68]

[22]

0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0 8.5 9.0 9.5 10.0 10.5 11.0 11.5 12.0 12.5 13.0

R-va lu e

Approximate Mile Post

Subgrade Test Results ( ≤ 6 ft) & Boring ID Cross Streets Design R-value (14% & 19%) R-value Results[#]

SW

-P

23-1-01373-109

Cascade Springs Road Cascade Scenic Drive Wasatch County, Utah

FIG. 2SHANNON & WILSON, INC.

VARIATION OF PAVEMENT

SUBGRADE SOILS

January 2018

Geotechnical and Environmental

SW

-B

-0

SW

-B

-0

SW

-B

-0

SW

-B

-0

SW

-B

-1

SW

-B

-1

SW

-B

-1

SW

-B

-1

SW

-C

-0

SW

-C

-0

SW

-C

-0

SW

-P

-0

SW

-P

-0

SW

-P

-0

SW

-P

-0

SW

-P

-0

SW

-P

-0

SW

-P

-0

SW

-P

-1

SW

-P

-1

SW

-P

-1

SW

-P

-1

SW

-P

-1

SW

-P

-1

SW

-P

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Cascade Springs Road (Phase 1)Cascade Scenic Drive (Phase 2)

St a.

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23-1-01373-109

PAVEMENT DESIGN CALCULATIONS

23-1-01373-109-R2-A 23-1-01373-109 A-i

PAVEMENT DESIGN CALCULATIONS

Cascade Springs Road and Cascade Scenic Drive Traffic Study

Flexible Pavement 18-kip Equivalent Single-Axle Loading (ESAL) Worksheet (2 sheets)

Flexible Pavement Design Worksheets (4 sheets)

Begin Project

End Project

UDOT

Count Station:

049‐0596 AADT = 471 Average (2010‐2014 – 5 Years)

AADT 2014 = 565

Count Station:

051‐0065 AADT = 2322 Average (2012–2014 3 Years)

Count Station:

051‐0060 AADT = 2678 Average (2012‐2014 3 Years)

Estimated AADT = 357

US‐92 to Cascade Springs (FH 114) Projected Growth = 2.2% US‐92 Estimated 2018 AADT=590 Traffic Split 92/FH114 = 60/40 Seasonal Adjustment = 50% FH 114 Estimated 2018

AADT = 240

Seasonal AADT = 360 Projected 2028

AADT = 370

Seasonal AADT = 560

Cascade Springs

Tate Ln to Cascade Springs Projected Growth = 0.75% Tate Ln Estimated 2018 AADT=390 Traffic Split Local Rds/Cascade = 70/30 Seasonal Adjustment = 70% Cascade Spr. Rd Estimated 2018

AADT = 120

Seasonal AADT = 200 Projected 2028

AADT = 200

Seasonal AADT = 330 Tate Ln daa Rectangle daa Rectangle daa Rectangle daa Rectangle

1/5/2018 Cascade Spring - ESAL Calc per 93 AASHTO-Rev1.xlsx Page 2 of 2 23-1-01373-109

Location: Cascade Springs Road (Phase 1) Comment: Analysis based on Table D.21 of the 1993 AASHTO Guide for the Design of Pavement Structures

Equations Paving Year: 2018 b = 2017 ADT * (a/100)

Pavement Design Life (D): 25 years(3) c = b * 365 2018 AADT: 120 vehicles per day d = [(1+r/100)25-1]/(r/100) 2028 AADT: 200 vehicles per day e = c * d

Growth Rate (r) : 5.24 %, 2028 AADT = 2018 AADT (1+r)^10 years g = e * f j = g * h * i a b c d e f g h i j

Traffic (1)

Percentage

AADT

Total

Traffic

Growth Factors

Design Traffic Volume

(total two-way volume)

Flexible (2)

Pavement Equivalency

Factor

Roadway Design

18k ESAL

Directional(4)

Distribution Factor

Traffic(4)

Lane Factor

Design Lane

18k ESAL

1) Motorcycles 0 0 0 49.34 0 0 0 0.6 1.0 0

2) Passenger Cars 42.5 85 31,025 49.34 1,530,890 0.0006 919 0.6 1.0 551

3) Pickups, Vans 42.5 85 31,025 49.34 1,530,890 0.0022 3,368 0.6 1.0 2,021

4) Buses 0 0 0 49.34 0 1.25 0 0.6 1.0 0

5) 2-Axle, 6-Tire Single Unit Trucks 0 0 0 49.34 0 0.50 0 0.6 1.0 0

6) 3-Axle, Single Unit Trucks

Pickup Truck with RV Trailer (S&W Calculated) 15 30 10,950 49.34 540,314 0.0640 34,580 0.6 1.0 20,748

7) 4-Axle or More, Single Unit Trucks 0 0 0 49.34 0 1.50 0 0.6 1.0 0

8) 4-Axle or Less, Single Trailer Trucks 0 0 0 49.34 0 1.75 0 0.6 1.0 0

9) 5-Axle Single Trailer Trucks 0 0 0 49.34 0 2.15 0 0.6 1.0 0

10) 6 or More Axle Single Trailer Trucks 0 0 0 49.34 0 2.15 0 0.6 1.0 0

11) 5 or Less Axle Multi-Trailer Truck 0 0 0 49.34 0 3.0 0 0.6 1.0 0

12) 6-Axle Multi-Trailer Trucks 0 0 0 49.34 0 3.0 0 0.6 1.0 0

13) 7 or More Axle Multi-Trailer Trucks 0 0 0 49.34 0 3.0 0 0.6 1.0 0

100 200 3,602,095 38,867 23,320

Notes 1) 2)

3) 4)

5) A compounded growth rate was determined by current and projected traffic loading as provided by CH2M

Exhibit 11.2-A of the 2008 Federal Lands Highway Project Development and Design Manual provides common truck factor ranges for each FHWA vehicle classification. The average value was assumed in our analysis for passenger cars, pickup trucks, and vans. The calculated ESAL factor for an Pickup Truck with RV trailer is based on the mean pickup truck esal factor plus an RV consisting of a single axle loaded with 9 kips.

The minimum design life for a reconstruction project (4R) is 25 years based on the 2008 Federal Lands Highway Project Development and Design Manual.

The 2008 Federal Lands Highway Project Development and Design Manual recommends a directional distribution factor of 0.6 and lane distribution factor of 1.0 percent for a two lane (two direction) road.

Flexible Pavement 18-kip Equivalent Single-Axle Loading (ESAL) Worksheet

FHWA Vehicle Classification and Description

All Vehicles

Design ESAL 24,000The current and projected AADT were provided by CH2M with the approximate traffic distribution.

1/5/2018 Cascade Spring - ESAL Calc per 93 AASHTO-Rev1.xlsx Page 1 of 2 23-1-01373-109

Location: Cascade Scenic Drive (Phase 2) Comment: Analysis based on Table D.21 of the 1993 AASHTO Guide for the Design of Pavement Structures

Equations Paving Year: 2018 b = 2017 ADT * (a/100)

Pavement Design Life (D): 25 years(3) c = b * 365 2018 AADT: 240 vehicles per day d = [(1+r/100)25-1]/(r/100) 2028 AADT: 370 vehicles per day e = c * d

Growth Rate (r) : 4.42 %, 2028 AADT = 2018 AADT (1+r)^10 years g = e * f j = g * h * i a b c d e f g h i j

Traffic (1)

Percentage

AADT

Total

Traffic

Growth Factors

Design Traffic Volume

(total two-way volume)

Flexible (2)

Pavement Equivalency

Factor

Roadway Design

18k ESAL

Directional(4)

Distribution Factor

Traffic(4)

Lane Factor

Design Lane

18k ESAL

1) Motorcycles 0 0 0 44.10 0 0 0 0.6 1.0 0

2) Passenger Cars 42.5 102 37,230 44.10 1,642,010 0.0006 985 0.6 1.0 591

3) Pickups, Vans 42.5 102 37,230 44.10 1,642,010 0.0022 3,612 0.6 1.0 2,167

4) Buses 0 0 0 44.10 0 1.25 0 0.6 1.0 0

5) 2-Axle, 6-Tire Single Unit Trucks 0 0 0 44.10 0 0.50 0 0.6 1.0 0

6) 3-Axle, Single Unit Trucks

Pickup Truck with RV Trailer (S&W Calculated) 15 36 13,140 44.10 579,533 0.0640 37,090 0.6 1.0 22,254

7) 4-Axle or More, Single Unit Trucks 0 0 0 44.10 0 1.50 0 0.6 1.0 0

8) 4-Axle or Less, Single Trailer Trucks 0 0 0 44.10 0 1.75 0 0.6 1.0 0

9) 5-Axle Single Trailer Trucks 0 0 0 44.10 0 2.15 0 0.6 1.0 0

10) 6 or More Axle Single Trailer Trucks 0 0 0 44.10 0 2.15 0 0.6 1.0 0

11) 5 or Less Axle Multi-Trailer Truck 0 0 0 44.10 0 3.0 0 0.6 1.0 0

12) 6-Axle Multi-Trailer Trucks 0 0 0 44.10 0 3.0 0 0.6 1.0 0

13) 7 or More Axle Multi-Trailer Trucks 0 0 0 44.10 0 3.0 0 0.6 1.0 0

100 240 3,863,554 41,687 25,012

Notes 1) 2)

3) 4)

5) A compounded growth rate was determined by current and projected traffic loading as provided by CH2M

Exhibit 11.2-A of the 2008 Federal Lands Highway Project Development and Design Manual provides common truck factor ranges for each FHWA vehicle classification. The average value was assumed in our analysis for passenger cars, pickup trucks, and vans. The calculated ESAL factor for an Pickup Truck with RV trailer is based on the mean pickup truck esal factor plus an RV consisting of a single axle loaded with 9 kips.

The minimum design life for a reconstruction project (4R) is 25 years based on the 2008 Federal Lands Highway Project Development and Design Manual.

The 2008 Federal Lands Highway Project Development and Design Manual recommends a directional distribution factor of 0.6 and lane distribution factor of 1.0 percent for a two lane (two direction) road.

Flexible Pavement 18-kip Equivalent Single-Axle Loading (ESAL) Worksheet

FHWA Vehicle Classification and Description

All Vehicles

Design ESAL 26,000The current and projected AADT were provided by CH2M with the approximate traffic distribution.

Cascade Spring - Flexible Pavement Worksheet-Rev0.xlsm Page 1 of 4 23-1-01373-109

Flexible Pavement Design Worksheet

Location: Cascade Springs Road (Phase 1) Comment: Analysis based on the 1993 AASHTO Guide for the Design of Pavement Structures (AGDPS) with parameter guidelines from the 2008 Federal Lands Highway Project Development and Design Manual (PDDM).

Alternative: HACP over UTBC

1. Pavement Design Life: (PDDM) for Reconstruction Projects 25 years

2. Traffic Loading (W18): (Min. ESAL per Section 11.2.1.2) 18k ESALs: per lane

3. Serviceability:

p0: 4.2 (PDDM) ∆PSI: 2.2 pt: 2.0 (PDDM) for ADT < 500 vehicles per day

4. Subgrade Resilient Modulus (MR):

AASHTO R-value to MR correlation: MR(psi) = A + B x (R-value) A = 772 to 1,155 and B = 369 to 555 (use low-bound values) MR: 7,800 psi

The mean of the R-value trests results is 19%, MR = 7,783 psi

5. Reliability:

R: 75 % (PDDM) for ADT < 2,500 vehicles per day ZR: -0.674

6. Design Standard Deviation (So):

So: 0.49 (PDDM)

7. Required Structural Numbers (SNi):

SN1: 1.144 0.0

SN2: 1.871 0.0

SN3: -NA- #VALUE!

Layer Analysis

8. Pavement Materials Characterization: UTBC - Untreated Aggregate Base Course (Item 308) & HACP (Item 401)

MR ~ 25,000 psi

Layer

1 a1: 0.44 (PDDM) 2 a2: 0.12 m2: 1.00 (PDDM) 3 a3: m3:

9. Solutions for thicknesses: [ Figure 3.2, Part II of 1993 AASHTO] SN*1 = a1D*1 >= SN1

SN*2 = a1D*1 + a2D*2m2 >= SN2

SN*3 = a1D*1 + a2D*2m2 + a3D*3m3 >= SN3

Layer SN*i SNi

1 3.0 inches 1.320 1.144 2 6.0 inches 2.040 1.871 3 inches

Note: Required SN <= Pavement SN, Design is Acceptable

50,000

AGDPS Table 4.1 (Prt I)

Analysis MR

25,000

-NA-

Material Structural Layer Coefficients

Drainage Coefficients

Layer Modulus (psi)

7,800

Recommended Thicknesses Material Thickness (D*i)

HACP - -

UTBC 25,000

HACP

UTBC

07.8)(log32.2

)1( 109440.0

5.12.4 log

20.0)1(log36.9)(log 10

19.5

101810 −+

+−++= RoR M

SN

PSI

SNSZW

Cascade Spring - Flexible Pavement Worksheet-Rev0.xlsm Page 2 of 4 23-1-01373-109

Flexible Pavement Design Worksheet

Location: Cascade Springs Road (Phase 1) Comment: Analysis based on the 1993 AASHTO Guide for the Design of Pavement Structures (AGDPS) with parameter guidelines from the 2008 Federal Lands Highway Project Development and Design Manual (PDDM).

Alternative: HACP over Pulverized FDR

1. Pavement Design Life: (PDDM) for Reconstruction Projects 25 years

2. Traffic Loading (W18): (Min. ESAL per Section 11.2.1.2) 18k ESALs: per lane

3. Serviceability:

p0: 4.2 (PDDM) ∆PSI: 2.2 pt: 2.0 (PDDM) for ADT < 500 vehicles per day

4. Subgrade Resilient Modulus (MR):

AASHTO R-value to MR correlation: MR(psi) = A + B x (R-value) A = 772 to 1,155 and B = 369 to 555 (use low-bound values) MR: 7,800 psi

The mean of the R-value trests results is 19%, MR = 7,783 psi

5. Reliability:

R: 75 % (PDDM) for ADT < 2,500 vehicles per day ZR: -0.674

6. Design Standard Deviation (So):

So: 0.49 (PDDM)

7. Required Structural Numbers (SNi):

SN1: 1.049 0.0

SN2: 1.144 0.0

SN3: 1.871 -2.54226E-05

Layer Analysis

8. Pavement Materials Characterization: FDR - Mixture of Pulverized HACP (Item 303) & HACP (Item 401)

Layer

1 a1: 0.44 (PDDM) 2 a2: 0.12 m2: 1.00 (PDDM) 3 a3: 0.10 m3: 0.80

9. Solutions for thicknesses: [ Figure 3.2, Part II of 1993 AASHTO] SN*1 = a1D*1 >= SN1

SN*2 = a1D*1 + a2D*2m2 >= SN2

SN*3 = a1D*1 + a2D*2m2 + a3D*3m3 >= SN3

Layer SN*i SNi

1 3.0 inches 1.320 1.049 2 4.0 inches 1.800 1.144 3 4.0 inches 2.120 1.871

Note: Required SN <= Pavement SN, Design is Acceptable

50,000

AGDPS Table 4.1 (Prt I)

Analysis MR

30,000

7,800

Material Structural Layer Coefficients

Drainage Coefficients

Layer Modulus (psi)

25,000

Recommended Thicknesses Material Thickness (D*i)

HACP - -

UTBC 30,000

FDR - Pulverizing 25,000

HACP

UTBC

FDR - Pulverizing

07.8)(log32.2

)1( 109440.0

5.12.4 log

20.0)1(log36.9)(log 10

19.5

101810 −+

+−++= RoR M

SN

Cascade Spring - Flexible Pavement Worksheet-Rev0.xlsm Page 3 of 4 23-1-01373-109

Flexible Pavement Design Worksheet

Location: Cascade Senic Drive (Phase 2) Comment: Analysis based on the 1993 AASHTO Guide for the Design of Pavement Structures (AGDPS) with parameter guidelines from the 2008 Federal Lands Highway Project Development and Design Manual (PDDM).

Alternative: HACP over Pulverized FDR

1. Pavement Design Life: (PDDM) for Reconstruction Projects 25 years

2. Traffic Loading (W18): (Min. ESAL per Section 11.2.1.2) 18k ESALs: per lane

3. Serviceability:

p0: 4.2 (PDDM) ∆PSI: 2.2 pt: 2.0 (PDDM) for ADT < 500 vehicles per day

4. Subgrade Resilient Modulus (MR):

AASHTO R-value to MR correlation: MR(psi) = A + B x (R-value) A = 772 to 1,155 and B = 369 to 555 (use low-bound values) MR: 6,000 psi

The mean of thelow-bound R-value trests results is 14%, MR = 5,938 psi

5. Reliability:

R: 75 % (PDDM) for ADT < 2,500 vehicles per day ZR: -0.674

6. Design Standard Deviation (So):

So: 0.49 (PDDM)

7. Required Structural Numbers (SNi):

SN1: 1.144 0.0

SN2: 2.069 0.0

SN3: -NA- #VALUE!

Layer Analysis

8. Pavement Materials Characterization: FDR - Mixture of Pulverized HACP (Item 303) & HACP (Item 401)

Layer

1 a1: 0.44 (PDDM) 2 a2: 0.10 m2: 1.00 (PDDM) 3 a3: m3:

9. Solutions for thicknesses: [ Figure 3.2, Part II of 1993 AASHTO] SN*1 = a1D*1 >= SN1

SN*2 = a1D*1 + a2D*2m2 >= SN2

SN*3 = a1D*1 + a2D*2m2 + a3D*3m3 >= SN3

Layer SN*i SNi

1 3.0 inches 1.320 1.144 2 8.0 inches 2.120 2.069 3 inches

Note: Required SN <= Pavement SN, Design is Acceptable

HACP

FDR - Pulverizing

Recommended Thicknesses Material Thickness (D*i)

HACP - -

FDR - Pulverizing 25,000

-NA-

Material Structural Layer Coefficients

Drainage Coefficients

Layer Modulus (psi)

50,000

Analysis MR

25,000

6,000

AGDPS Table 4.1 (Prt I)

07.8)(log32.2

)1( 109440.0

5.12.4 log

20.0)1(log36.9)(log 10

19.5

101810 −+

+−++= RoR M

SN

Cascade Spring - Flexible Pavement Worksheet-Rev0.xlsm Page 4 of 4 23-1-01373-109

Flexible Pavement Design Worksheet

Location: Cascade Senic Drive (Phase 2) Comment: Analysis based on the 1993 AASHTO Guide for the Design of Pavement Structures (AGDPS) with parameter guidelines from the 2008 Federal Lands Highway Project Development and Design Manual (PDDM).

Alternative: HACP over UTBC

1. Pavement Design Life: (PDDM) for Reconstruction Projects 25 years

2. Traffic Loading (W18): (Min. ESAL per Section 11.2.1.2) 18k ESALs: per lane

3. Serviceability:

p0: 4.2 (PDDM) ∆PSI: 2.2 pt: 2.0 (PDDM) for ADT < 500 vehicles per day

4. Subgrade Resilient Modulus (MR):

AASHTO R-value to MR correlation: MR(psi) = A + B x (R-value) A = 772 to 1,155 and B = 369 to 555 (use low-bound values) MR: 6,000 psi

The mean of thelow-bound R-value trests results is 14%, MR = 5,938 psi

5. Reliability:

R: 75 % (PDDM) for ADT < 2,500 vehicles per day ZR: -0.674

6. Design Standard Deviation (So):

So: 0.49 (PDDM)

7. Required Structural Numbers (SNi):

SN1: 1.049 0.0

SN2: 2.069 0.0

SN3: -NA- #VALUE!

Layer Analysis

8. Pavement Materials Characterization: UTBC - Untreated Aggregate Base Course (Item 308) & HACP (Item 401)

MR ~ 25,000 psi

Layer

1 a1: 0.44 (PDDM) 2 a2: 0.12 m2: 1.00 (PDDM) 3 a3: m3:

9. Solutions for thicknesses: [ Figure 3.2, Part II of 1993 AASHTO] SN*1 = a1D*1 >= SN1

SN*2 = a1D*1 + a2D*2m2 >= SN2

SN*3 = a1D*1 + a2D*2m2 + a3D*3m3 >= SN3

Layer SN*i SNi

1 3.0 inches 1.320 1.049 2 7.0 inches 2.160 2.069 3 inches

Note: Required SN <= Pavement SN, Design is Acceptable

UTBC 30,000

Recommended Thicknesses Material Thickness (D*i)

HACP

UTBC

Material Structural Layer Coefficients

Drainage Coefficients

Layer Modulus (psi)

HACP - -

-NA-

50,000

Analysis MR

30,000

6,000

AGDPS Table 4.1 (Prt I)

07.8)(log32.2

)1( 109440.0

5.12.4 log

20.0)1(log36.9)(log 10

19.5

101810 −+

+−++= RoR M

SN