NV FLAP 39(1) Kings Canyon Road Pavement and Materials Report.pdf

Hubmoldt-Toiyabe National Forest Carson City, Nevada

NV FLAP 39(1) Kings Canyon Road

PAVEMENT AND MATERIALS REPORT

March 2021 ii

Written by: ________________________________________________________ Marty Fey, Pavements and Materials Engineer

Reviewed by: ________________________________________________________ Mike Voth, Pavements and Materials Team Leader

Distribution:

Project Development Project Management Construction Materials Pavements Geotech iii

TABLE OF CONTENTS

I. INTRODUCTION

II. CLIMATE

III. EXPLORATION

IV. EXISTING PAVEMENT & SOILS

V. PAVEMENT DESIGN CALCULATION INPUTS

VI. PAVEMENT RECOMMENDATIONS & DISCUSSION

VII. MATERIALS RECOMMENDATIONS

APPENDICES

A – Location Map B – Laboratory Reports and Boring Log C – Photographs D – AASHTO ’93 Flexible Pavement Design E – PG LTPPBIND Software F – Preliminary Pavement Recommendation Memo G – Special Contract Requirements

I. INTRODUCTION

This report is written to document road conditions for the planned NV FLAP 39(1) Kings Canyon Road project. The project is located on the west side of Carson City, Nevada and consists of reconstructing approximately 1 mile of Kings Canyon Road from the crossing of Kings Canyon Creek to the Kings Canyon Waterfall trailhead. The project also includes the construction of an expanded trailhead parking area. See Appendix A for project location map.

The Preliminary Pavement Recommendations Memo was issued in February of 2019.

The memo provided the pavement recommendations as well as the proposed pay items.

This memo is found in Appendix F. The pavement recommendations have been finalized and are discussed in Part VI of this report.

II. CLIMATE

Climate data was obtained from weatherforyou.com. This data is summarized in Table 1 below. The average precipitation for this area is approximately 9.67 inches per year. The project is located in a mountainous area and at an elevation that receives both snow and rain, dependent upon the time of year.

Table 1: Weather Data

Month Average

LOW

Average

HIGH

Average

MEAN

Average

PRECIP.

January 23 47 35 1.56

February 28 53 40 1.57

March 31 59 45 1.12

April 37 67 52 0.45

May 44 76 60 0.44

June 50 86 68 0.44

July 53 90 72 0.18

August 48 85 66 0.23

September 39 75 57 0.40

October 31 61 46 0.69

November 24 48 36 1.24

December 21 44 33 1.35

Temperatures are in °F and precipitations are in inches.

III. EXPLORATION

On December 12th, 2018, a pavement and subgrade soil investigation was conducted which included boring and subgrade sampling. Tabor Drilling was hired through the CFLHD BPA to complete the shallow borings. Seven borings were logged, seven bulk subgrade samples were taken and four samples were tested in the laboratory. Prior to the investigation, CFL made a separate trip to mark proposed boring locations. CFL also called 811 for utility locations prior to the investigation. The pavement and subgrade investigation used a truck mounted CME 55 drill rig with an 8” solid core auger to drill through the existing pavement and to continue into the subgrade to 5 feet in depth. CFL personnel logged the borings; this included depth of boring, visual soil classification, and pavement thickness. Boring locations, test results, and other information is shown in Appendix B.

IV. EXISTING PAVEMENT & SOILS

Pavement thickness of Kings Canyon Road was found to be 4.0 inches in depth at the seven locations drilled, supported by native subgrade material. No aggregate road base was observed under the pavement. Generally speaking, the pavement and underlying subgrade appeared to stay consistent throughout the project.

The subgrade materials encountered are of good quality. The subgrade soils found consisted of silty sands and were classified as A-2-4(0) and A-4(0) with low plasticity and generally good R-values. See the laboratory reports and boring logs in Appendix B for more information.

Drilling efforts were relatively easy. No boulders were encountered during the drilling exploration. However, because this project is located in the Carson Range, boulders and cobbles may be encountered during construction.

V. PAVEMENT DESIGN CALCULATION INPUTS

Design Parameters

Traffic counts were provided with the FLAP application and used to developed estimates for ESALs. The road is primarily used for recreational and residential access with little commercial use. Truck counts were based on engineering judgement and are assumed to be very low. The counts appear generally consistent with other historical traffic data and they align with what was experienced during the field investigation. Design factors used in the ESALs calculations as well as the structural coefficients were taken from the CFLHD Project Development Design Manual (PDDM), Chapter 11.

In developing the pavement structural and rehabilitation recommendations the following criteria was used:

Table 2: Design Criteria

ADT (2019) 600

Growth Rate 2% Percent Trucks (1% Class 5, 1% Class 8) 2% Initial Serviceability 4.2 Terminal Serviceability 2.5 Design Reliability Level 75% Overall Standard Deviation 0.49 Soil Resilient Modulus (average R-value = 51) 15,000 psi Performance Period (4R) 20 years Directional Factor 0.50 20-year ESAL 56,800 Existing Borrow Material Average R-Value 63 Calculated Structural Number (SN) 1.47

Roadbed Soil Resilient Modulus

The soil resilient modulus was converted from R-Values, AASHTO T 190, using the following equation:

Resilient Modulus (psi) = 10[ ( S

+ 18.72 ) / 6.24 ] where S1 = [(R-Value – 5) / 11.29] + 3

An average R-value of 63 was used to generate a design resilient modulus of 20,000 psi.

A max allowable resilient modulus of 15,000 psi was used.

VI. PAVEMENT RECOMMENDATIONS & DISCUSSION

Utilizing AASHTO 93 Flexible Pavement Design (Appendix D), an adequate pavement section was developed. A full depth reclamation approach is recommended; aggregate base course may be used in widened or reconstructed areas. A pavement section of 3” HACP is sufficient to meet the structural requirements for a 20-year service life, however, Carson City requires a minimum of 4” HACP be used.

Table 3: Recommended Pavement Section

Layer Thickness

HACP

4 inches (two lifts)

Full Depth Reclamation or

Aggregate Base Course

6 inches

SN = 2.32

For the parking area it is recommended that a minimum section of one 2.5” lift of HACP on 6” of ABC be used. Gravel overflow areas should be constructed using 4” of ABC.

There were observed to be 26 driveways on the project. Of those, 14 are asphalt, 2 are concrete, and 10 are aggregate surfaced. It is recommended that the project utilize a replace in kind approach to tie these driveways into the new pavement.

VII. MATERIALS RECOMMENDATIONS

Selection of Asphalt Binder

LTPPBind software and NDOT standards were utilized to assist in the selection of asphalt binder. The information presented in LTPPBind is shown in Appendix E.

LTPPBind indicated that a PG 64-28NV binder should be used. Consideration was given to the location of the project as well as performance of past projects in similar condition.

Prime and Tack Coats, Blotter and Fog Seal

Prime Coat and Blotter are recommended for this project. A tack coat applied between pavement lifts is recommended. It is also recommended that a fog seal be applied to the final surfacing.

Drainage and Subexcavation

During the field investigation, areas of pavement distress were present. However, they appeared to be caused due to fatigue and age. No major water damage or drainage problems pertaining to the existing traveled way were observed. Should any drainage issues exist, the scope of the project allows for partial reconstruction. A quantity of 500 tons of subexcavation should be included in the contract. This quantity should remain in the Contract in the event that areas in need of repair are encountered.

Bid Items

Suggested FP-14 pay items for the proposed structural section are shown in Table 2 below.

Table 4: Recommended Pay Items

Item Number Item Description Unit

20402-0000 Subexcavation CUYD

30201-2000 Roadway Aggregate, Method 2 TON

30401-5300 Full Depth Reclamation, Method 2, 6-inch MILE

40301-0100 Hot Asphalt Concrete Pavement, Type 1 TON

40601-0000 Fog Seal TON

41102-1000 Prime Coat, Method 1 SQYD

41201-0000 Tack Coat TON

Construction Considerations & Special Contract Provisions

CFLHD standard SCR’s related to pavements & materials will be used. The attached SCR for Section 702. – Asphalt Materials should be used.

APPENDICES

A – Location Map

B – Laboratory Reports and Boring Log

C – Photographs

D – AASHTO ’93 Flexible Pavement Design

E – PG LTPPBind Software

F – Preliminary Pavement Recommendation Memo

G – Special Contract Requirements

Section 702. – Asphalt Materials

Appendix A: Location Map

Appendix B: Laboratory Reports and Boring Logs

Project:

Sample

Number

Station or

Location

Offset

(from c/l)

Date

Sampled

Depth of

Bore

Container

Type

Pavement

Depth

Base

Depth R‐Value Soil Class

0 to 4"

4" to 5' 4" 0" 66 A‐4(0)

0 to 4"

4" to 5' 4" 0"

0 to 4"

4" to 5' 4" 0" 64 A‐2‐4(0)

0 to 4"

4" to 5' 4" 0"

0 to 4"

4" to 5' 4" 0"

0 to 4"

4" to 5' 4" 0" 61 A‐2‐4(0)

0 to 4"

4" to 5' 4" 0" 59 A‐4(0) 5' to 10'

B‐8 Parking Area

10'RT 12/12/2018

5' 5‐gal bucket

5‐gal bucket

5'12/12/2018

B‐7

10' 5‐gal bucket

Asphalt Soil: A‐4(0), SC‐SM;

LL=22, PI=4;

117.2pcf@12.7%mc

Boring taken to a depth of 10' due to potential cuts/fills in the parking area.

12/12/2018 5' 5‐gal bucket

Soil: A‐2‐4(0), SM; LL=NL, PI=NP; 132.7pcf@8.0%mc

Asphalt

5' 5‐gal bucket

Sand silty/clayey, brown, moist Sand clayey, slightly moist, brown

12‐Dec‐18 Pavement Investigation ‐ Shallow Borings

Asphalt Sand silty, grey/brown, very moist

Asphalt

Boring Observations (grey = sample depth )

Soil: A‐4(0), SM; LL=NV, PI=NP;

122.9pcf@12.4%mc

Test Results Comments

0' No Sample

5‐gal bucket

Asphalt

12/12/2018

B‐5

Not drilled due to conflict with overhead lines.

3'RTB‐3

B‐4 3'LT

Investigation Boring & Sampling

Grey color and incresed moisture in low area near bridge.

B‐2 5'RT 12/12/2018

NV FLAP 39(1) Kings Canyon Road Account Number:

Entered By: Date of Investigation:Investigation By:Marty Fey Marty Fey

12/12/20184'LT

20' W of BridgeB‐1 5'

5‐gal bucket

Asphalt

Sand silty w/ some gravel, brown, moist

Sand silty w/ some gravel, brown, moist

Sand silty w/ some gravel, brown, moist

Sand silty w/ some gravel, brown, moist

Sand silty w/ some gravel, brown, moist

Note: Grey background indicates sample depth location.

Soil: A‐2‐4(0), SM; LL=NV, PI=NP; 132.6pcf@6.6%mc

Asphalt

B‐6 3.5'RT 12/12/2018

12/12/20185'LT 5'

6'LT

Appendix C: Photographs

Photo 1 – Typical Pavement Distress

Photo 2 – Typical Pavement Distress

Photo 3 – Trailhead Parking Area

Photo 4 – Drilling Operations

Photo 5 – Typical Asphalt Driveway

Photo 6 ‐ Typical Concrete Driveway

Appendix D: AASHTO ’93 Flexible Pavement Design

AASHTO FLEXIBLE PAVEMENT DESIGN

SN Determination

Design Inputs W18 = 56,800 ESALs Applications Over Design Period Typ. Range 50k to 10 million

R = 75 % Reliability Typ. Range 75 to 95%

So = 0.49 Standard Deviation AASHTO Standard

MR = 15,000 psi Subgrade Resilient Modulus Typ. Range 3000 to 15000 psi

Pi = 4.2 Initial Serviceability Typ. Range 4.2 to 4.4

Pt = 2.5 Terminal Serviceability Typ. Range 2.0 to 3.0

DESIGN SN = 1.47

AASHTO FLEXIBLE PAVEMENT DESIGN

Layer Thickness Determination Using Trial and Error

Layer Drainage Layer Layer No. Description Coefficient, ai Coefficient, mi Thickness, in SN

(topmost) Layer 1 AC Layer 0.40 1.00 4.00 1.60 Layer 2 FDR 0.12 1.00 6.00 0.72 Layer 3 Gran. Subbase 0.12 1.00 0.00 0.00 Layer 4 Select Borrow 0.08 0.90 0.00 0.00 Layer 5 0.00 Layer 6 0.00 Layer 7 0.00

(bottommost) Layer 8 0.00 Subgrade Subgrade N/A N/A N/A N/A

AC Layer 401 = 0.44 Trial SN 2.32

403 = 0.40

CAB 301 = 0.14 Design SN to Match 1.47 Subbase/Minor agg 302 = 0.12

FDR 304 = 0.12 Design is sufficient Select borrow 204 = 0.06 to 0.08

(Refer to Exhibit 11.2-C in Chapter 11 of PDDM for additional guidance on coefficients)

R-Value = 59 S1 = 7.783 MR = 17672 R-Value = 66 S1 = 8.403 MR = 22214

R‐Value Correlation to Resilient Modulus*

Only change the R-values in C4 or C5. The rest is automatically calculated.

*CDOT method. Similar to results from Figure FF.6 in Volume 2 of AGDPS and used by CFLHD.

ADT 600 Annual Growth 0.02 Design Years 20

Directional Distribution

0.5

Lane Distribution

Classification Percent Truck

Factor Growth Factor ADT Yr 1

Design Lane

ESALs ADT at N

Autos 65.0% 0.0006 390 0 580 Values Pickups, Vans 33.0% 0.004 24.29737 198 3512 294

892 (calculated) Class 4 buses 0.0% 1.5 24.29737 0 0 0 600 Class 5 trucks/RVs 1.0% 0.5 24.29737 6 13303 9 2015 Class 6 0.0% 1 24.29737 0 0 0 2035 Class 8 1.0% 1.5 24.29737 6 39908 9

2 Class 9 0.0% 2 24.29737 0 0 0 100.00% 56723 892

(refer to Exhibit 11.2‐A in the PDDM for additional guidance on truck factors)

GR = Growth Rate (%)

Future ADT Calculation ADTf = ADTi (1 + GR)(F‐I)

ADTf = Average daily traffic for future year ADTi = Average daily traffic for initial year

I = Initial year for ADT F = Future year for ADT

Appendix E: PG LTPPBind Software

BindReport-5Closest

Five Closest Weather Stations For Latitude/Longitude= 39.235/119.921 Report Date: 2/11/2019 (LTPPBind V3.0 Alpha)

NV FLAP 39(1) Kings Canyon Road

General A=16 km B=19 km C=19 km D=23 km E=24 km Station ID NV1485 NV3205 CA8758 CA0931 CA9043 County/District carson city douglas placer nevada nevada Weather Station carson city glenbrook tahoe city boca truckee ranger Elevation, m 1317 1799 1765 1579 1705 Latitude, Longitude 39.15 ,119.77 39.08 ,119.95 39.17 ,120.13 39.38 ,120.1 39.33 ,120.18 Last Year Data Available 1997 1997 1997 1996 1997

Air Temperature Mean ( Std, N ) Mean ( Std, N ) Mean ( Std, N ) Mean ( Std, N ) Mean ( Std, N ) High Temperature 35.1 (12,35) 29.7 (13,31) 28.6 (12,35) 32.5 (13,35) 31.6 (15,33) Low Temperature -20.3 (50,35) -14.5 (36,35) -17.4 (33,35) -26.5 (57,34) -21.9 (38,34) Low Temperature Drop 28.6 (25,35) 20.5 (31,35) 23.3 (21,35) 33.4 (32,34) 28.1 (22,34) Degree-Days > 10C 2990 (182,35) 2055 (178,31) 1865 (214,35) 2444 (224,35) 2247 (223,33)

PG High Low Rel. High Low Rel. High Low Rel. High Low Rel. High Low Rel.

Pavement Temperature, C 56.5 -13.6 47.9 -09.4 46.0 -11.5 51.7 -18.1 49.8 -14.8 50% Reliability PG 58-16 (92,72) 52-10 (98,58) 46-16 (53,92) 52-22 (63,80) 52-16 (98,64) >50% Reliability PG 58-22 (92,97) 52-16 (98,97) 52-16 (98,92) 58-22 (98,80) 52-22 (98,98) = 64-22 (98,97) 52-22 (98,98) 52-22 (98,98) 58-28 (98,98) = 64-28 (98,98)

Michael.Voth Highlight

Michael.Voth Highlight

Appendix F: Preliminary Pavement Recommendations Memo

Appendix G: Special Contract Requirements

Section 702. — ASPHALT MATERIAL

702.01 Asphalt Binder. Delete the Subsection and add the following:

702.01 Asphalt Binder. Conform to M 320, Table 1.

In AASHTO M 320, Table 1 replace footnote g with the following:

g If the creep stiffness is below 300 MPa, the direct tension test is not required. If the creep stiffness is between 301 and 600 MPa, the creep stiffness value shall be used. The m-value requirement must be satisfied in both cases.

702.01 Asphalt Cement. Add the following:

Asphalt binder for the asphalt concrete pavement will be Grade PG 64-28NV conforming to Table 702-2. Blend the PG 64-28NV at the source of supply and deliver as a completed mixture to the job site.

Table 702-2 Asphalt Binder Grade PG 64-28NV

Test Test Method Requirement

Tests on Original Binder:

Flash point, °C AASHTO T 48 230 Min.

Viscosity @ 135°C, Pas AASHTO T 316 3.00 Max.

Dynamic Shear, G*/sin , Test Temp 64°C @ 10 rad/s, kPa AASHTO T 315 1.00 Min.

Ductility @ 4°C, 5 cm/min, cm AASHTO T 51 50 Min.

Toughness @ 25°C, in-lbs ASTM D 5801 110 Min.

Tenacity @ 25°C, in-lbs ASTM D 5801 75 Min.

Tests on Residue from R.T.F.O., AASHTO T 240:

Mass Loss, % AASHTO T 240 1.00 Max.

Dynamic Shear, G*/sin , Test Temp 64°C @ 10 rad/s, kPa AASHTO T 315 2.20 Min.

Ductility @ 4°C, 5 cm/min, cm AASHTO T 51 25 Min.

Tests on Residue from Pressure Aging Vessel, AASHTO R28 @ 100°C:

Dynamic Shear, G*sin , Test Temp 22°C @ 10 rad/s, kPa AASHTO T 315 5000 Max.

Creep Stiffness, S, Test Temp 18°C @ 60 sec, MPa AASHTO T 313 300 Max.

Creep Stiffness, m-value, Test Temp 18°C @ 60 sec AASHTO T 313 0.300 Min.