subject: geotechnical investigation for pavement ......the following report presents the findings,...

November 25, 2015

Mr. David Aguirre The Holt Group 1601 N. Imperial Ave El Centro, CA 92243

SUBJECT: GEOTECHNICAL INVESTIGATION FOR PAVEMENT IMPROVEMENTS Imperial Avenue, Wake Avenue, and Danenberg Drive El Centro, California

Dear Mr. Aguirre:

The following report presents the findings, conclusions, and recommendations of our

investigation for the proposed pavement improvements to sections of Imperial Avenue, Wake

Avenue, and Danenberg Drive.

1.0 PURPOSE AND SCOPE OF WORK

The purpose of our investigation was to evaluate the existing geotechnical conditions beneath

the area of the proposed road reconstruction, and to provide geotechnical recommendations for

structural pavement sections, and excavation and grading. The recommendations contained

herein are based on a surface reconnaissance, subsurface investigation, laboratory testing,

engineering analysis, and our previous experience in the site vicinity. The scope of services

provided during this investigation was generally as described in our proposal No. EC15-013, dated

March 13, 2015. Our scope of work included the following items:

A visual reconnaissance and subsurface exploration of the site. A Bobcat-mounteddrill rig was used to explore the subsurface conditions at six boring locations. Selectedsoil samples were collected for laboratory testing. Logs of the explorations arepresented in Appendix A.

Laboratory testing of selected samples collected during the subsurface exploration.Testing was intended to assist in characterizing and assessing pertinent engineeringproperties of the on-site soils. Laboratory test results are presented in Appendix B.

Imperial Avenue Extension – The Holt Group November 25, 2015 EC461

Engineering analysis of field and laboratory data to make recommendations regarding pavement sections, site preparation, earthwork, and trench backfill.

Preparation of this report summarizing our findings, conclusions and recommendations.

2.0 SITE DESCRIPTION

The site topography is generally flat with a ground surface elevation of approximately minus 27

feet (± 5 feet) Mean Sea Level (MSL). Agricultural fields and residential subdivisions surround the

roadways. Irrigation canals associated with the agricultural fields are aligned with many area

roadways. An Exploration Plan is presented in Figure 1.

3.0 PROPOSED DEVELOPMENT

The planned improvements include South Imperial Avenue between Highway 8 and West

McCabe Road, and will include the currently unpaved portions of Wake Avenue and Danenberg

Drive to the east. It is our understanding that the improvements will include the regrading of the

existing roadways and pavement with asphalt concrete and aggregate base sections. It is

anticipated that grading may involve cuts of up to approximately 5 feet from existing grade.

4.0 GEOLOGY AND SUBSURFACE CONDITIONS

The site is located within the north-central portion of the Salton Trough, a topographic and

structural depression bound to the north by the Coachella Valley and to the south by the Gulf of

California. The trough was created along with the Gulf of California by complex rifting and strike

slip faulting associated with the separation of Baja from mainland Mexico by the East Pacific Rise.

As the rift opened, the trough was filled with sediments derived from the adjacent mountains.

The bottom of the trough is formed by Mesozoic and older metamorphic and crystalline rock.

Tertiary marine and nonmarine deposits make up most of the 15,000 feet of sediment estimated

to overlie the basement. The upper 3,000 feet of the Salton Trough is underlain by Pleistocene

and Holocene-age lacustrine (lake) deposits.


Specifically, the site is underlain by lacustrine deposits which may be mantled with a thin layer of

fill. Because the composition and characteristics of the fill are similar, the fill is not differentiated

from the lacustrine deposits for purposes of this report. Generalized descriptions of the

subsurface materials encountered in our explorations are as follows:

4.1 Lacustrine Deposits

Lacustrine deposits were encountered in all six borings. As observed on site, the lacustrine deposits which are anticipated to be present below the asphalt and base course pavement section vary from lean clay (Unified Soil Classification CL), to low plasticity sandy silt (ML). The clays are moderate brown, moist, and stiff. The silts are moderate, fine grained, moist, and stiff in consistency.

4.2 Groundwater

Piezometers were installed in borings B-1, B-4, and B-6 to monitor stabilized free

groundwater levels. The piezometers were installed and read on October 19, 2015 and

then read again on November 6, 2015. Free groundwater was not observed in any of the

readings. It has been our experience that groundwater levels may fluctuate over time due

to changes in irrigation activity.

5.0 CONCLUSIONS

It is our opinion that the proposed improvements are feasible from a geotechnical standpoint

provided that the following recommendations and appropriate construction practices are

followed. Based on the results of our field investigation, laboratory testing and engineering

analyses, we have developed the following conclusions regarding the pertinent geotechnical

conditions at the site.

• Groundwater was not encountered in the borings during drilling, or in subsequent

readings 18 days later. Although free groundwater was not present, soil moistures in

zones are within the range at which the soils will show plastic behavior resulting in

pumping conditions when worked with equipment. The high moisture will also result in


over optimum moisture conditions (relative to the compaction curves) and would require

drying back before placing as compacted fill. The high moisture areas appear in random

areas and are likely the result of perched water conditions. Recommendations for

subgrade stabilization are provided in this report.

• The unpaved shoulders are likely to be underlain by shallow undocumented fill overlying

lacustrine deposits.

• The subgrade soils for the proposed pavement section will consist lean clay and clayey

silt. Laboratory testing indicates an R-Value of 5 would be appropriate for the subgrade

conditions.

• Excavations should be achievable using standard heavy equipment. Excavations may

generate wet soil that will need to be dried prior to placement as compacted fill.

6.0 RECOMMENDATIONS

The remainder of this report presents recommendations regarding earthwork construction and

the geotechnical aspects of the pavement improvements. These recommendations are based on

empirical and analytical methods typical of the standard of practice in southern California. If

these recommendations do not appear to cover a specific feature of the project, please contact

our office for amendments.

6.1 Plan Review

We recommend that Sierra Material Testing and Inspection review improvement plans

prior to finalization in order to evaluate conformance with the intent of the

recommendations contained within this report.

6.2 Excavation and Grading Observation

Sierra Material Testing and Inspection should observe pavement construction, site

grading and trench excavations and backfill. Sierra Material Testing and Inspection should


provide observation and testing services continuously during pavement construction,

grading and backfill operations. Such observations are considered essential to identify

field conditions that differ from those anticipated by the preliminary investigation, to

adjust designs to actual field conditions, and to determine that the earthwork is

accomplished in general accordance with the recommendations provided in this report.

Recommendations presented in this report are contingent upon Sierra Material Testing

and Inspection performing such services. Our personnel should perform sufficient testing

of pavement construction, fill and trench backfill to support our professional opinion as

to compliance with the compaction recommendations.

6.3 Earthwork

Pavement construction, grading and earthwork should be conducted in accordance with

the applicable local grading ordinance, Caltrans, and the most recent edition of the

Standard Specifications for Public Works Construction “Greenbook”. The following

recommendations are provided regarding specific aspects of the proposed earthwork

construction. These recommendations should be considered subject to revision based on

field conditions observed by the geotechnical consultant.

6.3.1 General: General site preparation should include the removal of deleterious

materials from the proposed improvement areas. Deleterious materials include

vegetation, trees and roots, trash, construction or demolition debris (such as

asphalt concrete pavements or Portland cement concrete improvements, and

rocks with greatest dimensions in excess of 6 inches. Deleterious materials are

not considered suitable for use in trench backfill, and should be removed from the

site.

Surficial loose fill may be present at existing road shoulders and other areas. Any

loose fill not removed during the planned roadway cuts should be removed to

exposed firm native soil. This should be evaluated by the geotechnical consultant

during grading. The design grade may then be achieved by filling with uniformly

compacted soil.


6.3.2 Fill Compaction: All fill and trench backfill to be placed in association with

the proposed improvements should be accomplished at slightly over optimum

moisture conditions using equipment that is capable of producing a uniformly

compacted product. The minimum relative compaction recommended for fill is

90 percent of the maximum dry density based on ASTM D1557. Sierra Material

Testing and Inspection should perform sufficient observation and testing of fill and

backfill so that an opinion can be rendered as to the compaction achieved.

6.3.3 Temporary Excavations: Excavations should conform to Cal-OSHA

guidelines. Temporary trench excavations should be observed by Sierra Material

Testing and Inspection in order to identify potentially adverse geologic conditions.

Excavations deeper than 3 feet should be shored or laid back to a 1:1 gradient for

heights up to 10 feet. Excavations that expose seepage or adverse geologic

conditions should be evaluated by our firm for additional recommendations.

Excavations that will be subjected to vehicle or equipment loads within a 1:1 plane

from the bottom of the trench should be engineered by the contractors registered

professional engineer in accordance with OSHA guidelines.

6.3.4 Construction Dewatering: Based on conditions observed during this

investigation, the need for construction dewatering is not anticipated.

6.3.5 Subgrade Stabilization: The bottom of all excavations should be firm and

unyielding prior to placing compacted fill. In areas of saturated and yielding (or

“pumping”) subgrade conditions, the yielding area may be stabilized by placing a

layer of geogrid (such as Tensar BX1200 or approved similar) directly on the

excavation bottom. The geogrid should be installed in accordance with the

product manufacturer’s recommendations. The geogrid should then be covered

with between 12 and 24 inches of minus ¾-inch crushed rock. The thickness of

rock needed to stabilize the excavation bottom may be determined in the field by

trial and error. Our experience suggests that 1 to 2 feet of rock should generally

be sufficient to stabilize most conditions.


6.4 Pavements

Pavement section thickness is based in part on the traffic index (TI) assigned to the

roadway, based on the anticipated vehicle volume and loading. Sections for various traffic

indices are provided below. The appropriate traffic index should be determined by the

City’s Department of Public Works.

Testing performed on the subgrade soil collected from our investigation indicated an R-

value of 5. The pavement structural sections were determined using the design criteria of

Caltrans Topic 608.4. Calculations for the various traffic indices are provided in Appendix

C. The pavement design is summarized below:

Traffic Index Asphalt Concrete Class 2 Aggregate Base

5 3 10

6 3 14

7 4 16

8 5 18

9 6 20

10 6 24

Subgrade preparation should be conducted immediately prior to the placement of the

pavement section. The upper 12 inches of pavement subgrade should be scarified,

brought to about optimum moisture content and compacted to at least 90 percent of

maximum dry density based on ASTM D1557 guidelines. Asphalt concrete should be

compacted to at least 95 percent based on the Hveem unit weight.

Asphalt concrete should conform to Section 26 of the Caltrans Standard Specifications or

Section 400-4 of the SSPWC. Aggregate base should conform to the specifications for Class

2 aggregate base as defined in Section 26-1.02A of the Caltrans Standard Specifications

or to crushed aggregate, crushed miscellaneous base, or processed miscellaneous base

as defined in Section 200-2 of the “Greenbook.”


7.0 LIMITATIONS

This investigation was performed using the degree of care and skill ordinarily exercised, under

similar circumstances, by reputable geotechnical consultants practicing in this or similar

localities. No warranty, express or implied, is made as to the conclusions and professional

opinions included in this report. The samples taken and used for testing, and the observations

made are believed representative of the project site. However, soil and geologic conditions can

vary significantly between borings. If this occurs, the changed conditions must be evaluated by

the geotechnical consultant and additional recommendations made, if warranted.

The findings of this report are valid as of the present date. However, changes in the condition of

a property can occur with the passage of time, whether due to natural processes or the work of

man on this or adjacent properties. In addition, changes in applicable or appropriate standards

of practice may occur from legislation or the broadening of knowledge. Accordingly, the findings

of this report may be invalidated wholly or partially by changes outside our control. Therefore,

this report is subject to review and should not be relied upon after a period of three years.

***

Sincerely, SIERRA Material Testing & Inspection Alex Rojas Anthony F. Belfast, P.E. Office Manager Senior Engineer

McCabe Road

La B

ruch

erie

Ave

nue

S. C

lark

Roa

d

McCabe Road

8

N. Im

peria

l Ave

.

Wake Avenue Wake Avenue

Cypr

ess

Dr.

PROPOSEDPROJECTLOCATION

La B

ruch

erie

Ave

nue

8

Danenberg DriveNuffer Road

Valleyview Ave.

Manuel Ortiz Ave.

City Limits

City Limits

City Limits

THG Project No. 135.033May 29, 2015

PROJECT LOCATIONMAP

South

8th S

treet

Imperial Avenue Extension South(from I-8 to Mc Cabe Road)

El Centro, CA. 92243

ApproximateBorings Locations

Imperial Avenue Extension – The Holt Group November 25, 2015 EC461 Page 9

APPENDIX A

SUBSURFACE EXPLORATION

Field exploration consisted of a visual reconnaissance of the site, and the drilling of six

exploratory borings on October 19, 2015. The exploratory borings were drilled using an 8-inch

diameter, continuous flight, hollow stem, Bobcat-mounted mounted drill rig. Bulk samples were

collected for laboratory testing. The maximum depth of exploration was 15 feet. Piezometer

standpipes were installed in borings B-1, B-4, and B-6 to permit longer term monitoring of free

groundwater. The approximate locations of the borings are shown on the Exploration Plan,

Figure 2. Logs describing the subsurface conditions encountered are presented in Figures A-1

through A-6.

The borings were located by visually estimating and pacing distances from landmarks shown on

the Exploration Plan. The locations should not be considered more accurate than is implied by

the method of measurement used and the scale of the map. The lines designating the interface

between different soils on the logs may be abrupt or gradational. Further, soil conditions at

locations between the borings may be substantially different from those at the specific locations

explored. It should be recognized that the passage of time could result in changes in the soil

conditions reported in our logs.

Symbol Explanationfree groundwaterperched or confined seepage

DATE DRILLED: Existing Elevation: california samplerLOGGED BY: Proposed Elevation: standard samplerEQUIPMENT: Shelby tube sampler

UN

DIS

T. S

AM

PLE

BU

LK

SA

MPL

E

BL

OW

S/FO

OT

UN

IT W

EIG

HT

(PC

F)M

OIS

TU

RE

CO

NT

EN

T (%

)

Moderate brown, moist, stiff, clayey silt with fine sand(ML)

Moderate brown, moist, stiff, lean clay (CL)

total depth: 10 feet, no groundwater

piezometer installed

EXPLORATIONBORING LOG

LOG OF EXPLORATION BORING A-1

10/19/15OM

DE

PTH

(FE

ET

)

Bobcat-mounted, 8" auger

DESCRIPTION

16.5

14.0

LAB TESTS

Project No. EC-461 Figure A-1

1

2

3

4

8

9

10

11

12

13

14

5

15

6

7



UN

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S/FO

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EIG

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(PC

F)M

OIS

TU

RE

CO

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EN

T





3/6/14AFBBobcat-mounted, 8" auger

DE

PTH

(FE

ET

)

LAB TESTSDESCRIPTION

2

1

4

3

6

5

8

725.9

10

9

12

11

14

13


15



UN

DIS

T. S

AM

PLE

BU

LK

SA

MPL

E

BL

OW

S/FO

OT

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EIG

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(PC

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TU

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DE

PTH

(FE

ET

)


2

1

4

3

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5

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7 14.0

10 20.2

9

12

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13


15



UN

DIS

T. S

AM

PLE

BU

LK

SA

MPL

E

BL

OW

S/FO

OT

UN

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EIG

HT

(PC

F)M

OIS

TU

RE

CO

NT

EN

T (%

)

Brown, moist, stiff, clayey silt (ML)

Brown, moist, stiff, lean clay (CL) `

total depth: 15 feet, no groundwaterpiezometer installed




DE

PTH

(FE

ET

)


2

1

4

3

67.6 max density/

5

8

7 opt moisture

10 opt moisture

919.2 max density/

12

11

14

1323.1


15



UN

DIS

T. S

AM

PLE

BU

LK

SA

MPL

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S/FO

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EIG

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(PC

F)M

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TU

RE

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Brown, moist, stiff, lean clay (CL)






DE

PTH

(FE

ET

)


2

1

4

3

6

5

818.4

7

10

9

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13

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UN

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T. S

AM

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SA

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(PC

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piezometer installed


Bobcat-mounted, 8" auger

DE

PTH

(FE

ET

)

DESCRIPTION LAB TESTS


3/6/14AFB

2

1

4

3

6

5

8

721.8

10

930.1 R-value

12

11

14

13


15


APPENDIX B LABORATORY TESTING

Laboratory testing was conducted in a manner consistent with that level of care and skill

ordinarily exercised by members of the profession currently practicing under similar

conditions and in the same locality. No warranty, express or implied, is made as to the

correctness or serviceability of the test results, or the conclusions derived from these tests.

Where a specific laboratory test method has been referenced, such as ASTM, Caltrans, or

AASHTO, the reference applies only to the specified laboratory test method and not to

associated referenced test method(s) or practices. The referenced test method referenced

has been used only as a guidance document for the general performance of the test and not

as a “Test Standard.” A brief description of the tests performed follows:

Classification: Soils were classified visually according to the Unified Soil Classification System

as established by the American Society of Civil Engineers. Visual classification was

supplemented by laboratory testing of selected soil samples and classification in general

accordance with the laboratory soil classification tests outlined in ASTM test method D2487.

The resultant soil classifications are shown on the boring logs in Appendix A.

In-Situ Moisture/Density: The in-place moisture content of selected soil samples were determined using bulk samples. The moisture contents are shown on the Boring Logs in Appendix A.

Maximum Density/Optimum Moisture: The maximum dry density and optimum moisture

content of selected soil samples were estimated in general accordance with the laboratory

procedures outlined in ASTM D1557, modified Proctor. The test results are summarized in

Figures B-1 and B-2

Atterberg Limits: The liquid limit, plastic limit, and plasticity index of selected fine-grained soil samples were estimated in general accordance with the laboratory procedures outlined in ASTM test method D4318. The results are given in Figure B-3.

R-Value: R-Value tests were performed on selected pavement area materials in general accordance with the laboratory procedures outlined in California Test Method 301. The results are presented on Figure B-4.

LABORATORY TEST RESULTSProject No. EC-461

Figure B-1

STANDARD TEST METHOD FORMOISTURE - DENSITY RELATIONSHIP(ASTM D1557)

REV Aug 2012

PROJECT: SAMPLE ID:PROJECT NO.: DATE:TESTED BY: CHECKED BY:SAMPLE DESCRIPTION:

A) WATER ADDEDB) MOLD TARE WEIGHTC) WEIGHT OF WET SOIL AND MOLDD) WET SOIL WEIGHT (C - B)E) WET DENSITY (D / V)F) DRY DENSITY (E / [(L/100) + 1])

G) TARE WEIGHTH) WEIGHT OF WET SOIL AND TAREI) WEIGHT OF DRY SOIL AND TAREJ) WEIGHT OF WATER (H - I)K) DRY WEIGHT OF SOIL (I - G)L) MOISTURE CONTENT (J / K * 100)

SIEVENUMBERPERCENTRETAINED

MAXIMUMDENSITY [PCF]

OPTIMUM MOISTURE [%]

16.0285.9267.018.9

251.07.5 9.6 11.6

248.5 237.6percent

1003 Industry Way, Suite A El Centro, CA 92243(760) 337-2067

31.6

16.0277.7246.1

15.9288.3264.423.9

15.9281.1253.527.6

Imperial Ave. ExtensionEC 461

MM

B-4 @ 6'October 26, 2015

3002021.0

1994.0

12.0

1502021.0 2021.03869.01848.0123.3

No.4

<5%

116.0

4 inch

230.113.7

4015.01926.03947.0

1990.0

200 2502021.04011.0

millilitersgramsgramsgrams

gramsgrams

gramsgrams

Clayey Silt

grams

pcfpcf

133.0117.0

132.8118.9114.6 117.2

128.5

MOLD VOLUME CORRECTION (V)

(A,B or C)

MOLDUSED

14.99

A

4 INCH (4-1): V=15.12 pcf/gm4 INCH (EC): V=15.07

METHOD USED

6 inch: V=34.15 pcf/gm6 INCH (EC): V=34.02

110

115

120

125

130

5 10 15 20

DRY

DEN

SITY

(pcf

)

WATER CONTENT (%)

Gs=2.6

Gs=2.7

Gs=2.8

Poly.(Series1)

ZERO AIR VOIDS


Figure B-2

STANDARD TEST METHOD FORMOISTURE - DENSITY RELATIONSHIP(ASTM D1557)

REV Aug 2012

PROJECT: SAMPLE ID:PROJECT NO.: DATE:TESTED BY: CHECKED BY:SAMPLE DESCRIPTION:

A) WATER ADDEDB) MOLD TARE WEIGHTC) WEIGHT OF WET SOIL AND MOLDD) WET SOIL WEIGHT (C - B)E) WET DENSITY (D / V)F) DRY DENSITY (E / [(L/100) + 1])

G) TARE WEIGHTH) WEIGHT OF WET SOIL AND TAREI) WEIGHT OF DRY SOIL AND TAREJ) WEIGHT OF WATER (H - I)K) DRY WEIGHT OF SOIL (I - G)L) MOISTURE CONTENT (J / K * 100)

SIEVENUMBERPERCENTRETAINED

MAXIMUMDENSITY [PCF]

OPTIMUM MOISTURE [%]

16.0273.3243.729.6

227.713.0 14.9 17.0

215.8 204.5percent

1003 Industry Way, Suite A El Centro, CA 92243(760) 337-2067

37.3

15.8249.4212.1

15.9263.9231.732.2

16.0255.2220.534.7

Imperial Ave. ExtensionEC 461

MM

B-4 @ 10.0October 26, 2015

3502021.0

1926.0

17.5

2002021.0 2021.03811.01790.0119.4

No.4

<5%

111.0

4 inch

196.319.0

3947.01870.03891.0

1944.0

250 3002021.03965.0

millilitersgramsgramsgrams

gramsgrams

gramsgrams

Clay

grams

pcfpcf

128.5108.0

129.7110.9105.7 108.6

124.7

MOLD VOLUME CORRECTION (V)

(A,B or C)

MOLDUSED

14.99

A

4 INCH (4-1): V=15.12 pcf/gm4 INCH (EC): V=15.07

METHOD USED

6 inch: V=34.15 pcf/gm6 INCH (EC): V=34.02

100

105

110

115

120

10 15 20

DRY

DEN

SITY

(pcf

)

WATER CONTENT (%)

Gs=2.6

Gs=2.7

Gs=2.8

Poly.(Series1)

ZERO AIR VOIDS

STANDARD TEST FOR ATTERBERG LIMITSASTM D 4318

SAMPLE I.D.: B4 @ 6'

Procedure Used:X wet preparation

dry preparationX procedure A

multipoint testprocedure B

one poin test

LIQUID LIMIT (LL): 29PLASTIC LIMIT (PL): 18

PLASTICITY INDEX (PI): 11

SAMPLE I.D.: B4 @ 10'

Procedure Used:X wet preparation

dry preparationX procedure A

multipoint testprocedure B

one poin test

LIQUID LIMIT (LL): 39PLASTIC LIMIT (PL): 18

PLASTICITY INDEX (PI): 21

LABORATORY TEST Project No. EC-461RESULTS

Figure B-3

0

10

20

30

40

50

60

0 10 20 30 40 50 60 70 80 90 100

Plas

ticity

Inde

x (P

I)

Liquid Limit (LL)

CL or OL

CH or OH

MH or OH

ML or OL cl-ml

0

10

20

30

40

50

60

0 10 20 30 40 50 60 70 80 90 100

Plas

ticity

Inde

x (P

I)

Liquid Limit (LL)

CL or OL

CH or OH

MH or OH

ML or OL cl-ml


Figure B-4

PROJECT NAME: PROJECT NUMBER: EC 461SAMPLE DESCRIPTION: DATE SAMPLED: 10/20/2015SAMPLE LOCATION: TECHNICIAN: MM

SAMPLE NUMBER:

TEST SPECIMEN a b cMOISTURE AT COMPACTION % 19.1 19.7 20.2HEIGHT OF SAMPLE, Inches 2.49 2.47 2.45DRY DENSITY, pcf 112.9 113.3 113.8COMPACTOR AIR PRESSURE, psi 100 75 50EXUDATION PRESSURE, psi 368 282 200EXPANSION, Inches x 10exp-4 85 65 40STABILITY Ph 2,000 lbs (160 psi) 143 145 148TURNS DISPLACEMENT 3.74 3.79 3.83R-VALUE UNCORRECTED 7 6 5R-VALUE CORRECTED 7 6 5R-VALUE BY EXUDATION

DESIGN CALCULATION DATA a b cGRAVEL EQUIVALENT NEEDED ft. 1.49 1.50 1.52TRAFFIC INDEXSTABILOMETER THICKNESS, ft. 0.93 0.94 0.95EXPANSION PRESSURE THICKNESS, ft. 2.83 2.17 1.33

EXPANSION PRESSURE CHART EXUDATION PRESSURE CHART

R-VALUE BY EXPANSION: 5R-VALUE BY EXUDATION: 6EQUILIBRIUM R-VALUE: 5

R-VALUE TEST RESULTS

Imperial ave ExtensionHeavy ClayB-7

6

5.0

0

10

20

30

40

50

60

70

80

90

0100200300400500600700800

R-V

ALU

E

EXUDATION PRESSURE (psi)

0.00

0.50

1.00

1.50

2.00

2.50

3.00

3.50

4.00

0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 4.00

COVER THICKNESS BY EXPANSION in feet

CO

VER

TH

ICKN

ESS

BY S

TABI

LOM

ETER

in fe

et


APPENDIX C PAVEMENT DESIGN

R-Value (S.G.): 5 FOR THE FOLLOWING STREETS:R-Value (A.B.): 78Safety Factor: 0.2

Gf (A.B.): 1.1 [ft] Gf (A.S.): 1.0 [ft]

CALCULATIONS RECOMMENDEDTraffic Index: 5.0 PAVEMENT SECTIONGf (A.C.): 2.54 [ft]GE (Total): 1.52 [ft]GE (A.C.): 0.35 [ft]GE (A.C.) + S.F.: 0.55 [ft]T (A.C.): 0.22 [ft] UseT (A.C.): (Rounded 0.05) 0.20 [ft] 2.4 [in] 3GE (A.C.): (Actual) 0.64 [ft] inches asphalt concreteGE ( A.B.): 0.89 [ft] overT (A.B.): 0.80 [ft] = 9.7 [in] 10GE (A.B.): (Actual) 0.92 [ft] inches of aggregate baseGE (Act. Tot): 1.55



PAVEMENT SECTIONDESIGN

FIGURE C-1

Imperial Ave,. Wake Ave,Danenberg Dr.

PAVEMENT CALCULATION SHEET(Based On CalTrans Topic 608.4)

Project No. EC-461

R-Value (S.G.): 5 FOR THE FOLLOWING STREETS:R-Value (A.B.): 78Safety Factor: 0.2

Gf (A.B.): 1.1 [ft] Gf (A.S.): 1.0 [ft]




PAVEMENT SECTIONDESIGN

FIGURE C-2

Imperial Ave,. Wake Ave,Danenberg Dr.

PAVEMENT CALCULATION SHEET(Based On CalTrans Topic 608.4)

Project No. EC-461

subject: geotechnical investigation for pavement ......the following report presents the findings,...

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