HONOLULU RAIL TRANSIT PROJECT UH WEST O’AHU …hartdocs.honolulu.gov/docushare/dsweb/Get/Document-20607/9.1.3 … · about 0.5 to 2.5 feet deep at the existing ground surface. Because

UHWO Construction Contract Reference Material

HONOLULU RAIL TRANSIT PROJECT

UH WEST O’AHU TEMPORARY PARK & RIDE AND CAMPUS ROAD ‘B’

CONSTRUCTION CONTRACT

GEOTECHNICAL ENGINEERING EXPLORATION UNIVERSITY OF HAWAII WEST OAHU ROAD ‘B’

FEBRUARY 11, 2011

W.O. 5822-40 GEOLABS, INC. Page i Hawaii ● California

GEOTECHNICAL ENGINEERING EXPLORATION

UNIVERSITY OF HAWAII WEST OAHU

DRIVEWAY “B”

EWA, OAHU, HAWAII

W.O. 5822-40 FEBRUARY 11, 2011

TABLE OF CONTENTS Page

SUMMARY OF FINDINGS AND RECOMMENDATIONS.............................................. iii

1. GENERAL ............................................................................................................ 1 1.1 Introduction ................................................................................................ 1 1.2 Project Considerations............................................................................... 1 1.3 Purpose and Scope ................................................................................... 1

2. SITE CHARACTERIZATION................................................................................ 3 2.1 Regional Geology ...................................................................................... 3 2.2 Existing Site Conditions ............................................................................. 4 2.3 Subsurface Conditions............................................................................... 4

3. DISCUSSION AND RECOMMENDATIONS ........................................................ 6 3.1 Site Grading............................................................................................... 6

3.1.1 Site Preparation.............................................................................. 7 3.1.2 Fills and Backfills............................................................................ 8 3.1.3 Fill Placement and Compaction Requirements .............................. 9 3.1.4 Boulder Fill ..................................................................................... 9 3.1.5 Cut and Fill Slopes ....................................................................... 11 3.1.6 Settlement Monitoring .................................................................. 12

3.2 Pavement Design .................................................................................... 12 3.3 Sidewalks................................................................................................. 13 3.4 Erosion Control Measures (Landscape)................................................... 14 3.5 Utility Trenches ........................................................................................ 15 3.6 Design Review......................................................................................... 16 3.7 Construction Monitoring ........................................................................... 16

4. LIMITATIONS..................................................................................................... 17

CLOSURE..................................................................................................................... 19 PLATES

Project Location Map................................................................................... Plate 1 Site Plan ...................................................................................................... Plate 2 Recommended Site Preparation Procedure ............................................... Plate 3 Recommended Boulder Fill Schematic Section........................................... Plate 4

TABLE OF CONTENTS

Page

W.O. 5822-40 GEOLABS, INC. Page ii Hawaii ● California

APPENDIX A Field Exploration ..................................................................................... Page A-1 Soil Log Legend ..........................................................................................Plate A Logs of Borings ........................................................................ Plates A-1 thru A-7

APPENDIX B Laboratory Tests ..................................................................................... Page B-1 Laboratory Test Data ............................................................... Plates B-1 thru B-9

W.O. 5822-40 GEOLABS, INC. Page iii Hawaii ● California

GEOTECHNICAL ENGINEERING EXPLORATION

UNIVERSITY OF HAWAII WEST OAHU

DRIVEWAY “B”

EWA, OAHU, HAWAII

W.O. 5822-40 FEBRUARY 11, 2011

SUMMARY OF FINDINGS AND RECOMMENDATIONS

Our field exploration at the project site generally encountered clayey alluvial soils

extending down to the maximum depth explored of approximately 16.5 feet below the existing ground surface. The alluvial soils encountered generally consisted of soft to very hard clays with some sands and gravels. We did not encounter groundwater in the borings at the time of our field exploration.

Based on our field observations, the surface soils at the project site are dry and friable. In addition, we observed substantial shrinkage cracks extending on the order of about 0.5 to 2.5 feet deep at the existing ground surface. Because of the observed ground conditions, we recommend implementing specific site preparation procedures during the earthwork construction for this project. The upper 12 inches of the soils below the existing ground surface should be stripped and removed as part of the clearing and grubbing operations, and the resulting spoils should be disposed properly off-site (or used in landscaped areas, if appropriate) because they contain an appreciable amount of organic materials and may be classified as “unsuitable” materials.

After clearing and grubbing to remove the upper 12 inches of the surface soils below the existing ground surface, the exposed soils should be over-excavated by at least another 12 inches, moisture conditioned to at least 2 percent above the optimum moisture content, and replaced as compacted fills. After over-excavation of the soils below the existing ground surface, the over-excavated subgrade areas should be scarified to a depth of at least 12 inches, moisture conditioned to at least 2 percent above the optimum moisture content, and compacted to no less than 90 percent relative compaction. The 12 inches of the over-excavated soils (not the 12 inches of materials removed as part of clearing and grubbing) may be re-used as a source of general fill materials provided that the materials are free of deleterious materials and are moisture-conditioned and compacted as recommended herein.

Deep fills up to 22 feet in depth are planned within the Kaloi Gulch area. For the purpose of discussion for this project, boulders are defined as rock fragments between 12 and 36 inches in largest dimension. Boulder fills should be located below 5 feet from finished subgrade and more than 8 feet from the finished slope face, if applicable. Boulder fills should not be placed in areas where future excavations for utilities will take place. Boulder fills should be placed in lifts not greater than 60 inches. A minimum 18-inch thick choking layer of well-graded granular fill materials with rock fragments ranging in size from about 8 inches to 1 inch in dimension should be placed on top of the boulder fill layer to

SUMMARY OF FINDINGS AND RECOMMENDATIONS

W.O. 5822-40 GEOLABS, INC. Page iv Hawaii ● California

seal off the voids of the boulder fill. The boulder fill should be watered heavily during placement and compaction. Conventional compaction testing is generally not practicable in fills composed of rocks, boulders, and/or cobbles. Instead, a testing program to evaluate the number of passes by a compactor needed to achieve the desired level of compaction should be conducted at the start of the grading phase of the project.

The assumed design traffic used in our pavement analysis for the new roadway consisted of a daily traffic of about 500 passenger vehicles, 10 two-axle trucks, and 8 three-axle trucks. Based on the moderately to highly expansive soil conditions, we recommend placing the pavement section on a minimum 18-inch thick non-expansive, select granular fill. Based on the above assumptions, a flexible pavement section consisting of 3.0 inches of asphaltic concrete underlain by 8 inches of aggregate base course may be considered.

The text of this report should be referred to for detailed discussions and specific design recommendations.

END OF SUMMARY OF FINDINGS AND RECOMMENDATIONS

W.O. 5822-40 GEOLABS, INC. Page 1 Hawaii ● California

SECTION 1. GENERAL

1.1 Introduction

This report presents the results of our geotechnical engineering exploration

performed for the proposed University of Hawaii West Oahu Driveway “B” project

located in the District of Ewa on the Island of Oahu, Hawaii. The project location and

general vicinity are shown on the Project Location Map, Plate 1.

This report summarizes the findings and our geotechnical recommendations

derived from our field exploration, laboratory testing, and engineering analyses. These

recommendations are intended for the design of site grading, pavements, and

underground utilities for the project only. The findings and recommendations presented

herein are subject to the limitations noted at the end of this report.

1.2 Project Considerations

The University of Hawaii West Oahu Campus covers approximately 103.5 acres

and is south and east of Farrington Highway and west of North-South Road in the

District of Ewa on the Island of Oahu, Hawaii. A new driveway is planned from

North-South Road to Kaloi Gulch.

We understand that the new roadway will be about 108 feet wide and about

1,040 feet long. The new roadway will consist of 12 and 10 feet wide traffic lanes, 6 feet

wide bike lane, and a 12 feet wide sidewalk in each direction. In addition, a 20 feet wide

median and turn bay is located in the middle of the roadway.

Based on the grading plans, fills up to about 6 and 22 feet are planned for the

roadway and within Kaloi Gulch, respectively. New utility lines (water, drain, and sewer)

will be constructed along the new roadway.

1.3 Purpose and Scope

The purpose of our exploration was to obtain an overview of the surface and

subsurface conditions at the project site. The subsurface information obtained was used

to develop an idealized soil data set to formulate geotechnical recommendations for the

design of site grading, pavements, and underground utilities for the proposed project.

SECTION 1. GENERAL


Our work was performed in general accordance with our fee proposal dated

September 7, 2010. The scope of work for our exploration included the following tasks

and work efforts.

1. Trail clearing with a loader to provide access to the boring locations for our truck-mounted drilling equipment.

2. Mobilization and demobilization of trail clearing equipment and a truck-mounted drill rig and operators to and from the project site.

3. Drilling and sampling of seven borings at the project site extending to depths of approximately 15.5 to 16.5 feet below the existing ground surface.

4. Collection of bulk soil samples for laboratory test analyses.

5. Coordination of the field exploration and logging of the borings by our field geologist.

6. Laboratory testing of selected samples obtained during the field exploration as an aid in classifying the materials and evaluating their engineering properties.

7. Engineering analyses of the field and laboratory data to develop geotechnical recommendations for the design of site grading, pavements, and underground utilities for the project.

8. Preparation of this report summarizing our work on the project and presenting our findings and geotechnical recommendations.

9. Coordination of our overall work on the project by our senior engineer.

10. Quality assurance of our work and client/design team consultation by our principal engineer.

11. Miscellaneous work efforts such as drafting, word processing, and clerical support.

Detailed descriptions of our field exploration methodology and the Logs of

Borings are provided in Appendix A. Results of the laboratory tests performed on

selected soil samples are presented in Appendix B.

END OF GENERAL


SECTION 2. SITE CHARACTERIZATION

2.1 Regional Geology

The Island of Oahu was built by the extrusion of basaltic lavas from the

Waianae and Koolau Shield Volcanoes. The older Waianae Volcano is estimated to be

middle to late Pliocene in age and forms the bulk of the western one-third of the island.

The younger Koolau Volcano is estimated to be late Pliocene to early Pleistocene (Ice

Age) in age and forms the majority of the eastern two-thirds of the island. As volcanic

activity in Waianae Volcano ceased, lava flows from Koolau Volcano banked against its

eroded eastern slope forming a broad plateau, known as Schofield Plateau. The Koolau

Volcano reached the end of its main shield-building phase about 2 million years ago.

Following extrusion of the lavas in the early Pleistocene Epoch, the island

underwent a long cycle of erosion and weathering forming the prominent ridgelines and

summits as we know today. During the erosion period, the Island of Oahu began to

slowly subside by more than 1,200 feet in elevation, resulting in the drowning and

sedimentation of the valleys and the formation of the steep Koolau Pali. Coral reefs

continued to grow in the surrounding shallow waters of the island.

From the mid to late Pleistocene Epoch, the sea level repeatedly rose and fell in

response to global glaciation and the availability of surface waters to sustain the

oceans. The various sea level elevations and their representative deposits are known

as “stands” and include from oldest to youngest: the Kahuku, Kahipa, Kaena, Laie,

Waialae, Waipio, and Waimanalo stands. Geologic deposits associated with the various

sea level stands, including marine sediments and coral reefs, were deposited and

subsequently altered or removed by later sea level fluctuation. Therefore, depositional

records reflecting the changes in sea level and the occurrence of emerged coral reef

deposits are often incomplete.

The project site is situated on the Ewa Plain to the southeast of the

Waianae Mountain Range. The Ewa Plain is a gently sloping alluvial plain formed by the

deposition of alluvial clays and silts derived from weathering of the basalt rock formation

further up-slope. The alluvial deposits were laid down and are inter-bedded with marine



sediments and coral/algal reef formations to form a sedimentary wedge. The thickness

of the sedimentary wedge ranges from zero in the area of the Interstate Route H-1

Highway to over 1,000 feet at Ewa Beach. This wedge forms the Ewa Plain and serves

as the confining formation, or “caprock,” over the artesian basal aquifers of southern

Oahu. Basalt rock formation resides below the marine deposits at a substantial depth.

The project site is situated over the relatively thick alluvial clay soils. The

coralline and marine deposits are believed to underlie the site but at some depth

beneath the alluvium. Agricultural developments within the last 100 years have brought

the area to its present form.

2.2 Existing Site Conditions

The University of Hawaii West Oahu Campus is south and east of Farrington

Highway and west of North-South Road in the District of Ewa on the Island of Oahu,

Hawaii, as shown on the Site Plan, Plate 2.

Presently, the site is occupied by vacant areas vegetated with wild grasses and

some sparse trees. Substantial shrinkage cracks were observed at the ground surface

within the project site. The shrinkage cracks ranged from about 6 inches up to 30 inches

in depth. Numerous shrinkage cracks were observed near the top of slope area

adjacent to Kaloi Gulch.

The project site generally slopes down toward the east from about 20 horizontal

to one vertical (20H:1V) to 50H:1V inclination. Steeper slopes from about 1H:1V to

2H:1V inclination are located within Kaloi Gulch. Based on the topographic survey map

provided, the existing ground surface elevations generally range from about +122 to

+140 feet Mean Sea Level (MSL) down to Elevation +108 feet MSL within Kaloi Gulch.

2.3 Subsurface Conditions

Our field exploration consisted of drilling and sampling seven borings, designated

as Boring Nos. 1 through 7, extending to depths of about 15.5 to 16.5 feet below the

existing ground surface. Two bulk samples of the near-surface soils, designated as

Bulk-1 and Bulk-2, were collected at selected locations along the new roadway to



evaluate the pavement support characteristics of the near-surface soils. The

approximate borings and bulk sample locations are shown on the Site Plan, Plate 2.

In general, the project site appears to be underlain by clayey alluvial soils over

the majority of the project site. The clayey alluvial soils extended down to the maximum

depth explored of approximately 16.5 feet below the existing ground surface.

The alluvial soils generally consisted of soft to very hard clays with some sands

and gravels. Cobbles and boulders were also encountered within the alluvial deposit. It

should be noted that the alluvial clays are moderately to highly expansive when

subjected to moisture fluctuations.

We did not encounter groundwater in the borings at the time of our field

exploration. However, it should be noted that water levels at the project site may be

influenced by seasonal precipitation and other factors.

Detailed descriptions of the field exploration methodology are presented in

Appendix A. Descriptions and graphic representations of the materials encountered in

the borings are provided on the Logs of Borings, Plates A-1 through A-7. Laboratory

tests were performed on selected soil samples, and the test results are presented in

Appendix B.

END OF SITE CHARACTERIZATION


SECTION 3. DISCUSSION AND RECOMMENDATIONS

Based on our field exploration, the University of Hawaii West Oahu Driveway “B”

project site generally is underlain by soft to very hard clayey alluvial soils extending

down to the maximum depth explored of approximately 16.5 feet below the existing

ground surface. Field observations during our exploration indicated the surface soils at

the project site are dry and friable. In addition, we observed substantial shrinkage

cracks on the order of about 0.5 to 2.5 feet deep at the existing ground surface.

Our laboratory tests indicate that the near-surface clayey soils exhibit moderate

to high shrink/swell characteristics when subjected to fluctuations in the soil moisture

contents. Therefore, special attention should be given to the site preparation

recommendations for the site grading design to account for the moderately to highly

expansive soil conditions at the site.

Based on our analysis, a flexible pavement section consisting of asphaltic

concrete underlain by aggregate base course and non-expansive select granular fill

material is recommended for the new roadway. Our geotechnical recommendations

pertaining to the design of site grading, pavements, and underground utilities are

discussed further in the following sections.

3.1 Site Grading

Based on our field observations, the surface soils at the project site are dry and

friable. In addition, we observed substantial shrinkage cracks of about 0.5 to 2.5 feet

deep at the existing ground surface. Because of the observed ground conditions at the

existing ground surface, we recommend implementing special site preparation

procedures during the earthwork construction for the project. Items of grading that are

addressed in the subsequent subsections include the following:

1. Site Preparation 2. Fills and Backfills 3. Fill Placement and Compaction Requirements 4. Boulder Fill 5. Cut and Fill Slopes 6. Settlement Monitoring



3.1.1 Site Preparation

In general, the areas within the contract grading limits should be cleared and

grubbed thoroughly at the on-set of earthwork. Vegetation, debris, deleterious

materials, and other unsuitable materials should be removed and disposed properly

off-site or disposed in a designated area to reduce the potential for contamination of

the excavated materials. The upper 12 inches of the soils below the existing ground

surface should be stripped and removed as part of the clearing and grubbing

operations, and the resulting spoils should be disposed properly off-site (or used in

landscaped areas, if appropriate) because they contain an appreciable amount of

organic materials. The upper 12 inches of the soils below the ground surface that

will be removed as part of the clearing and grubbing operations may be classified

as “unsuitable” materials and should not be used as fill for this project.

After clearing and grubbing to remove the upper 12 inches of the soils below the

existing ground surface, the normally dry and friable soils should be over-excavated

by at least another 12 inches, moisture conditioned to at least 2 percent above the

optimum moisture, and replaced as compacted fills. After over-excavation of the

soils below the existing ground surface, the over-excavated subgrade areas should

be scarified to a depth of at least 12 inches, moisture-conditioned to at least

2 percent above the optimum moisture content, and compacted to no less than

90 percent relative compaction. The 12 inches of the over-excavated soils (not the

12 inches of materials removed as part of clearing and grubbing) may be re-used

as a source of general fill materials provided that the materials are free of

deleterious materials and are moisture-conditioned and compacted as

recommended herein. The above site preparation procedure is shown on the

Recommended Site Preparation Procedure, Plate 3.

Relative compaction refers to the in-place dry density of soil expressed as a

percentage of the maximum dry density of the same soil established in accordance

with ASTM D 1557 test procedures. Optimum moisture is the water content

(percentage by dry weight) corresponding to the maximum dry density. The intent

of the recommended site preparation procedures serves to close up some of the

large shrinkage cracks observed at the site. We strongly recommend that a



Geolabs representative be present during and after the clearing and grubbing

operations to evaluate the exposed ground conditions prior to site preparation

operations.

Soft and/or yielding areas encountered at the bottom of the over-excavation below

areas designated to receive fill or future improvements should be over-excavated to

expose stiff and/or dense materials. The resulting excavation should be backfilled

with compacted on-site soils or replaced with select granular fill materials. The

excavated soft and/or organic soils should be disposed properly off-site or used in

landscaped areas, if appropriate. Contract documents should include additive and

deductive unit prices for over-excavation and compacted fill placement to account

for variations in the over-excavation quantities.

Where shrinkage cracks are noted after compaction of the subgrade, we

recommend preparing the soil again as recommended above. Saturation and

subsequent yielding of the exposed subgrade due to inclement weather and poor

drainage may require over-excavation of the soft areas and replacement with

well-compacted fill at no additional cost to the owner. A Geolabs representative

should evaluate the need for over-excavation in the field.

3.1.2 Fills and Backfills

In general, the excavated on-site materials (not including the 12 inches of soil

materials removed as part of clearing and grubbing) may be re-used as a source of

general fill materials if the materials are free of deleterious materials. Imported fill

materials should consist of non-expansive select granular fill materials, such as

crushed coralline or basaltic materials. The materials should be well graded from

coarse to fine with particles no larger than 3 inches in largest dimension and should

contain between 10 and 30 percent particles passing the No. 200 sieve. The

materials should have a laboratory CBR value of 25 or more and should have a

maximum swell of 1 percent or less.



3.1.3 Fill Placement and Compaction Requirements

General fill materials should be placed in level lifts not exceeding 8 inches in loose

thickness, moisture-conditioned to at least 2 percent above the optimum moisture

content, and compacted to at least 90 percent relative compaction. The compaction

requirements for finished subgrades subjected to vehicular traffic, such as the

pavement subgrade, should be increased to a minimum of 95 percent relative

compaction.

The non-expansive select granular fill materials required under the paved areas

(refer to the “Pavement Design” section) should be placed in level lifts of about

8 inches in loose thickness, moisture-conditioned to above the optimum moisture,

and compacted to at least 90 percent relative compaction (or 95 percent relative

compaction for finished subgrades subjected to vehicular traffic). Aggregate base

and aggregate subbase materials should be moisture-conditioned to above the

optimum moisture content, placed in level lifts not exceeding 8 inches in loose

thickness, and compacted to a minimum of 90 percent relative compaction.

Relative compaction refers to the in-place dry density of soil expressed as a

percentage of the maximum dry density of the same soil established in accordance

with ASTM D 1557. Optimum moisture is the water content (percentage by weight)

corresponding to the maximum dry density.

3.1.4 Boulder Fill

For the purpose of discussion on this project, boulders are defined as rock

fragments between 12 and 36 inches in largest dimension. Boulder fills should be

located below 5 feet from finished subgrade and more than 8 feet from the finished

slope face, if applicable. Boulder fills should also be kept out of utility alignments to

prevent difficulty in the later excavation of the utility trenches.

Prior to placement of boulders, the gulch area should be thoroughly cleared and

grubbed. Vegetation, debris, rubbish, and other unsuitable materials should be

removed and disposed of properly off-site. The upper 12 inches of the soils below

the existing ground surface should be stripped and removed as part of the clearing

and grubbing operations. Soft and yielding areas encountered during the clearing



and grubbing should be over-excavated to expose firm natural material, and the

resulting excavation should be backfilled with well-compacted engineered fill. Prior

to filling within the gulch area, the existing ground should be scarified to a depth of

18 inches, moisture-conditioned to at least 2 percent above the optimum moisture

and compacted to a minimum of 90 percent relative compaction.

Loose/soft soils at the gulch slope face and at the top of the gulch should be

removed to stiff natural ground prior to fill placement.

Prior to the start of the boulder fill placement, the lateral limits and elevations of the

area where boulder fills are to be placed should be surveyed. Boulder fills should

not be placed in areas where future excavations for utilities and/or foundations will

take place. In addition, the top elevations of the top and bottom of the boulder fill

should be plotted on the as-built grading plans for future reference.

Boulder fills should be placed in lifts not greater than 60 inches. Spreading and

compaction of each layer of the boulder fill should be accomplished with a

Caterpillar D-9 bulldozer (or larger) for a minimum of 6 to 8 passes to facilitate

“seating” of the boulders. The boulder fill should be watered heavily by water trucks

traversing in front of the current boulder lift face and sprayed with water

continuously during placement.

A minimum 18-inch thick choking layer of well-graded granular fill materials should

be placed on the top of the boulder fill layer to seal off the voids of the boulder fill.

The choking layer should consist of well-graded granular fill materials with rock

fragments ranging in size from about 8 inches to 1 inch in dimension.

The choking layer of well-graded granular fill should be watered heavily and

compacted with a 10-ton vibratory drum roller a minimum of 6 to 8 passes to

provide a firm surface. The upper 5 feet of fill material below the finished grades

should consist of 3-inch minus fill material compacted to at least 90 percent relative

compaction. The aforementioned recommendations are presented on the

Recommended Boulder Fill Schematic Section, Plate 4.



Conventional compaction testing is generally not practicable in fills composed of

rocks, boulders, and/or cobbles. Instead, a testing program to evaluate the number

of passes by a compactor needed to achieve the desired level of compaction

should be conducted at the start of the grading phase of the project under the

observation of a Geolabs representative. The minimum numbers of passes noted

above are preliminary estimates.

It should be noted that if the boulder fill is not placed in such a manner to obtain a

well-compacted fill mass, the boulder fill may need to be removed and

reconstructed to obtain a well-compacted mass.

3.1.5 Cut and Fill Slopes

We envision the cut slopes at the project site generally will expose the stiff to very

hard clays encountered in the borings drilled. In general, cut slopes and permanent

fill slopes constructed of the on-site soils may be designed with a slope inclination

of 2H:1V or flatter. Fills placed on slopes steeper than 5H:1V should be keyed and

benched into the existing slope to provide stability of the new fill against sliding. The

filling operations should start at the lowest point and continue up in level horizontal

compacted layers in accordance with the above general fill placement

recommendations. Fill slopes should be constructed by overfilling and cutting back

to the design slope ratio to obtain a well-compacted slope face. Surface water

should be diverted away from the tops of slopes, and slope planting should be

provided as soon as possible to reduce the potential for erosion of the finished

slopes.

Because moisture-conditioning and compaction of the clayey subgrade soils are

critical elements of the earthwork, Geolabs should perform observations and soil

density tests during site grading operations to assist the contractor in obtaining the

required degree of compaction and the proper moisture content on each fill lift.

Where compaction is less than required, additional compaction effort should be

applied with adjustment of the moisture content, as necessary, to obtain the

specified compaction. It should be noted that the moisture requirement of the

on-site fills, imported general fills, and soil subgrades (at least 2 percent above the



optimum moisture) is an important requirement considering the moderately to highly

expansive nature of the clayey soils. Therefore, observation and testing during the

site grading operations for this project should be designated as a “Special

Inspection” item under “Special Grading, Excavation and Filling.”

3.1.6 Settlement Monitoring

We understand that up to 22 feet of fill will be placed within Kaloi Gulch near the

end of Driveway “B” and for the future Campus Loop Road. We estimate about 2 to

4 inches of ground settlements may occur as a result of the up to 22 feet of new fill

placement within the gulch. Therefore, a settlement monitoring program should be

implemented for these areas and the paving of the new roadways should be

delayed to allow for the majority of the settlement to occur under the new load. We

recommend a settlement waiting period of about 3 to 4 weeks.

To monitor the settlement rate, we recommend installing settlement monitoring

points at the finished subgrade level. The monitoring points should be read

optically by a qualified professional surveyor, and the readings should be

transmitted to Geolabs for review. We recommend taking two readings (one day

apart) for each settlement point at the start of the monitoring period to establish a

baseline. Subsequent readings should be taken on a weekly basis for the entire

settlement period.

3.2 Pavement Design

We understand a flexible pavement will be used for the new roadway. In general,

we anticipate the future vehicle loading for the access driveway will consist of some

heavy vehicular traffic, including delivery and container trucks in addition to the

passenger vehicles and light pick-up trucks. In addition, a design life of 30 years was

used.

The assumed design traffic used in our pavement analysis for the new roadway

consisted of a daily traffic of about 500 passenger vehicles, 10 two-axle trucks, and

8 three-axle trucks. Based on the moderately to highly expansive soil conditions, we

recommend placing the pavement section on a minimum 18-inch thick non-expansive,



select granular fill in lieu of aggregate subbase course. Based on the above

assumptions, we recommend using the following flexible pavement section for

preliminary design purposes:

Flexible Pavement

3.0-Inch Asphaltic Concrete 8.0-Inch Aggregate Base Course (95 Percent Relative Compaction) 11.0-Inch Total Pavement Thickness over 18-Inch Select Granular Fill

The non-expansive, select granular fill should be placed in level lifts of about

8 inches in loose thickness, moisture-conditioned to above the optimum moisture, and

compacted to at least 90 percent relative compaction. The compaction requirement for

the final lift of the select granular fill should be increased to at least 95 percent relative

compaction. The clayey subgrades below the non-expansive, select granular fill should

be scarified to a depth of about 8 inches, moisture-conditioned to at least 2 percent

above the optimum moisture, and compacted to a minimum of 90 percent relative

compaction. The aggregate base course and aggregate subbase materials should

consist of crushed basaltic aggregates compacted to no less than 95 percent relative

compaction.

In general, paved areas should be sloped, and drainage gradients should be

maintained to carry the surface water off the site. Surface water ponding should not be

allowed on the site during or after construction. Where concrete curbs are used to

isolate landscaping in or adjacent to the pavement areas, we recommend extending the

curbs a minimum of 2 inches into the soils below the aggregate base course and

aggregate subbase layers to reduce the potential for migration of excessive landscape

water into the pavement section. Alternatively, a subdrain system could be constructed

to collect the excess water from landscaping irrigation. For long-term performance, we

suggest constructing a subdrain system adjacent to the paved/landscaped areas.

3.3 Sidewalks

Concrete slab-on-grade sidewalks will be constructed for the project. Unless

concrete slab-on-grade constructed above the expansive soils encountered at the

project site are properly designed, there is a potential for future distress to the lightly



loaded concrete sidewalks resulting from shrinking and swelling of the clayey soils due

to changes in the moisture content. To reduce the potential for appreciable structural

distress resulting from swelling of the subgrade soils, we recommend properly preparing

the subgrade soils prior to fill placement. In addition, we recommend providing a

minimum of 24 inches of non-expansive, select granular fill material below the sidewalk

slabs-on-grade. Construction joints should be provided at intervals equal to the width of

the sidewalk with expansion joints at right-angle intersections.

It should be noted that the moisture content requirement of the clayey subgrades

(at least 2 percent above the optimum moisture) is an important requirement

considering the expansive nature of the on-site clayey soils. Therefore, the subgrade

soils underneath the sidewalk should be properly moisture-conditioned and maintained

moist until placement of the select granular fill and concrete.

It should be emphasized that the areas adjacent to the slabs should be backfilled

tightly against the slab edges with low expansion, relatively impervious soils.

Additionally, these areas should be graded to divert water away from the slabs and to

reduce the potential for water ponding around the slabs.

3.4 Erosion Control Measures (Landscape)

As indicated previously, we observed substantial shrinkage cracks (on the order

of about 0.5 to 2.5 feet deep) at the existing ground surface of the project site based on

field observations. Shallower shrinkage cracks were noted in the areas that were

recently graded. In general, shrinkage cracks will develop in the ground due to the lack

of maintenance of the soil moisture content as the soils start to dry out under the sun

and dry weather conditions. The development of shrinkage cracks in the ground was

apparently intensified by the prolonged dry climatic conditions in the Ewa area resulting

in large fluctuations in the soil moisture content.

We recommend grassing the graded surfaces (including cut and fill slopes) to

reduce the potential for significant soil erosion soon after completion of the site grading.

The relatively dry climatic conditions of the Ewa area likely will require controlled

irrigation of the graded surfaces to maintain the moisture contents and to keep graded



surfaces free of large shrinkage cracks. However, over-watering of the graded surfaces

should be avoided to reduce the potential for saturation and softening of the surface

soils.

3.5 Utility Trenches

We understand that the utilities lines (water, drain, and sewer) will be installed

along the new roadway for the proposed project. In general, good construction practices

should be utilized for the installation and backfilling of the trenches for the proposed

utilities. The contractor should determine the method and equipment to be used for

excavation, subject to practical limits and safety considerations. The excavation should

comply with all applicable local, state, and federal safety requirements. The contractor

should be responsible for trench shoring design and installation. Trench shoring and

bracing should conform to the appropriate health and safety requirements.

In general, we recommend using granular bedding consisting of 6 inches of

open-graded gravel (ASTM C 33, No. 67 gradation) for support of the utility lines. The

initial trench backfill up to about 12 inches above the pipes should consist of

free-draining backfills, such as open-graded gravel, to reduce the potential for damaging

the pipes from compaction of the backfill. It is critical that a free-draining granular

material be used to reduce the potential for formation of voids below the haunches of

pipes and to provide adequate support for the sides of the pipes. The use of on-site

clayey soils as backfill directly around the utility pipes is not recommended and should

not be allowed.

The upper portion of the trench backfill from the level 12 inches above the pipes

to the finished subgrade may consist of approved on-site soils or select granular fill

material. The backfill material should be moisture-conditioned to above the optimum

moisture content, placed in level lifts not exceeding 8 inches in loose thickness, and

compacted to a minimum of 90 percent relative compaction to reduce the potential for

appreciable future ground subsidence. The upper 3 feet of the trench backfill below the

pavement grade should be compacted to not less than 95 percent relative compaction.

Mechanical compaction equipment should be used to compact the backfill material

considering the clayey nature of the on-site soils.



3.6 Design Review

Preliminary and final drawings and specifications for the proposed construction

should be forwarded to Geolabs for review and written comments prior to construction.

This review is needed to evaluate conformance of the plans and specifications with the

intent of the earthwork and pavement recommendations provided herein. If this review

is not made, Geolabs cannot assume responsibility for misinterpretation of our

recommendations.

3.7 Construction Monitoring

Due to the variability in the subsurface conditions, it is highly recommended to

retain Geolabs to provide geotechnical engineering services during the construction of

the project. The following are critical items of construction monitoring that require

"Special Inspection":

1. Removal of the cleared and grubbed materials 2. Subgrade preparation 3. Fill placement and compaction 4. Trench excavation and backfill

A Geolabs representative should monitor the other aspects of the earthwork

construction to observe compliance with the intent of the design concepts,

specifications, and/or recommendations, and to expedite suggestions for design

changes that may be required in the event that subsurface conditions differ from those

anticipated at the time this report was prepared. The recommendations presented

herein are contingent upon such observations.

If the actual exposed subsurface soil conditions encountered during construction

differ from those assumed or considered in this report, Geolabs should be contacted to

review and/or revise the geotechnical recommendations presented herein.

END OF DISCUSSION AND RECOMMENDATIONS


SECTION 4. LIMITATIONS

The analyses and recommendations submitted in this report are based in part

upon information obtained from the field borings and bulk samples. Variations of

subsurface conditions between and beyond the field borings and bulk samples may

occur, and the nature and extent of these variations may not become evident until

construction is underway. If variations then appear evident, Geolabs should be

contacted to re-evaluate the recommendations presented herein.

The field boring locations indicated in this report are approximate, having been

estimated by taping from the features shown on the grading plan received from

Engineering Concepts, Inc. on October 26, 2010. Elevations of the field borings were

interpolated from the spot elevations and contour lines shown on the same plan. The

physical locations and elevations of the field borings should be considered accurate

only to the degree implied by the methods used.

The stratification lines shown on the graphic representations of the borings depict

the approximate boundaries between the soil types, and as such, may denote a gradual

transition. Water level data from the borings were measured at the times shown on the

graphic representations and/or presented in the text herein. These data have been

reviewed and interpretations made in the formulation of this report. However, it must be

noted that fluctuation may occur due to variation in rainfall, temperatures, and other

factors.

This report has been prepared for the exclusive use of John Hara & Associates,

Inc. for specific application to the proposed University of Hawaii West Oahu

Driveway “B” project in accordance with generally accepted geotechnical engineering

principles and practices. No warranty is expressed or implied.

This report has been prepared solely for the purpose of assisting the architect

and engineers in the design of the proposed project. Therefore, this report may not

contain sufficient data, or the proper information, to serve as a basis for construction

cost estimates nor for bidding purposes. A contractor wishing to bid on this project

SECTION 4. LIMITATIONS


should retain a competent geotechnical engineer to assist in the interpretation of this

report and/or in the performance of additional site-specific exploration for bid estimating

purposes.

The owner/client should be aware that unanticipated subsurface conditions are

commonly encountered. Unforeseen soil conditions, such as perched groundwater, soft

deposits, hard layers, or cavities, may occur in localized areas and may require

additional probing or corrections in the field (which may result in construction delays) to

attain a properly constructed project. Therefore, a sufficient contingency fund is

recommended to accommodate these possible extra costs.

This geotechnical engineering exploration conducted at the project site was not

intended to investigate the potential presence of hazardous materials existing at the

site. The equipment, techniques, and personnel used to conduct a geo-environmental

exploration differ substantially from those applied in geotechnical engineering.

END OF LIMITATIONS

PLATES

APPENDIX A

W.O. 5822-40 GEOLABS, INC. FEBRUARY 2011 Page A-1 Hawaii ● California

A P P E N D I X A

Field Exploration

The subsurface conditions at the site were explored by drilling and sampling seven borings extending to depths of about 15.5 to 16.5 feet below the existing ground surface at the approximate locations shown on the Site Plan, Plate 2. The borings were drilled using truck-mounted and track-mounted drill rigs equipped with continuous flight augers. The materials encountered in the borings were classified by visual and textural examination in the field by our geologist, who observed the drilling operations on a near-continuous basis. These classifications were further reviewed by visual observation and testing in the laboratory. Soils were classified in general conformance with the Unified Soil Classification System, as shown on Plate A. Graphic representations of the materials encountered are presented on the Logs of Borings, Plates A-1 through A-7. Some soil samples were obtained from the drilled borings in general accordance with ASTM D 1586, Penetration Test and Split-Barrel Sampling of Soils, by driving a 2-inch OD standard penetration sampler with a 140-pound hammer falling 30 inches. In addition, some soil samples were obtained in general accordance with ASTM D 3550, Ring-Lined Barrel Sampling of Soils, by driving a 3-inch OD modified California sampler using the same hammer and drop. The blow counts needed to drive the sampler the second and third 6 inches of an 18-inch drive are shown as the “Penetration Resistance” on the Logs of Borings at the appropriate sample depths. Pocket penetrometer tests were performed on selected cohesive soil samples retrieved in the field. The pocket penetrometer test provides an indication of the unconfined compressive strength of the soil sample. The pocket penetrometer test results are presented on the Logs of Borings at the appropriate sample depths.

MORE THAN 50%OF COARSEFRACTION

RETAINED ONNO. 4 SIEVE

(2-INCH) O.D. STANDARD PENETRATION TEST

POCKET PENETROMETER (tsf)

UNCONFINED COMPRESSION (psi)

50% OR MORE OFCOARSE FRACTION

PASSINGTHROUGH NO. 4

SIEVE

MORE THAN 50%OF MATERIAL

RETAINED ON NO.200 SIEVE

50% OR MORE OFMATERIAL PASSINGTHROUGH NO. 200

SIEVE

TORVANE SHEAR (tsf)

TRIAXIAL COMPRESSION (ksf) A

(3-INCH) O.D. MODIFIED CALIFORNIA SAMPLE

SILTY GRAVELS, GRAVEL-SAND-SILTMIXTURES

OL

PEAT, HUMUS, SWAMP SOILS WITH HIGHORGANIC CONTENTS

INORGANIC CLAYS OF LOW TO MEDIUMPLASTICITY, GRAVELLY CLAYS, SANDYCLAYS, SILTY CLAYS, LEAN CLAYS

Soil Log Legend

UC

TV

ORGANIC CLAYS OF MEDIUM TO HIGHPLASTICITY, ORGANIC SILTS

SC

Plate

GM

FINE-GRAINED

SOILS

COARSE-GRAINED

SOILS

UNCONSOLIDATED UNDRAINED

CLEAN SANDS

SANDS WITHFINES

SP

SANDS

GRAVELS

WELL-GRADED GRAVELS, GRAVEL-SANDMIXTURES, LITTLE OR NO FINES

ML

CL

OH

LESS THAN 5%FINES

GRAVELS WITHFINES

CLEANGRAVELS

UU

PEN

PI

LL

INORGANIC SILTS AND VERY FINE SANDS,ROCK FLOUR, SILTY OR CLAYEY FINE SANDSOR CLAYEY SILTS WITH SLIGHT PLASTICITY

POORLY-GRADED GRAVELS, GRAVEL-SANDMIXTURES, LITTLE OR NO FINES

CLAYEY GRAVELS, GRAVEL-SAND-CLAYMIXTURES

WELL-GRADED SANDS, GRAVELLY SANDS,LITTLE OR NO FINES

POORLY-GRADED SANDS, GRAVELLYSANDS, LITTLE OR NO FINES

SILTY SANDS, SAND-SILT MIXTURES

CLAYEY SANDS, SAND-CLAY MIXTURES

GRAB SAMPLE

PLASTICITY INDEX (NP=NON-PLASTIC)

SILTSAND

CLAYS

SILTSAND

CLAYS

LIQUID LIMITLESS THAN 50

USCSTYPICAL

DESCRIPTIONS

GW

MORE THAN 12%FINES

HIGHLY ORGANIC SOILS

NOTE: DUAL SYMBOLS ARE USED TO INDICATE BORDERLINE SOIL CLASSIFICATIONS

SM

MAJOR DIVISIONS

GP

MORE THAN 12%FINES

PT

LESS THAN 5%FINES

UNIFIED SOIL CLASSIFICATION SYSTEM (USCS)

ORGANIC SILTS AND ORGANIC SILTYCLAYS OF LOW PLASTICITY

SW

GC

INORGANIC SILT, MICACEOUS ORDIATOMACEOUS FINE SAND OR SILTYSOILS

INORGANIC CLAYS OF HIGH PLASTICITY

LEGEND

CORE SAMPLE

WATER LEVEL OBSERVED IN BORING

LIQUID LIMIT50 OR MORE CH

MH

SHELBY TUBE SAMPLE

LIQUID LIMIT (NP=NON-PLASTIC)

GEOLABS, INC.

Geotechnical Engineering

LO

G L

EG

EN

D F

OR

SO

IL

58

22

-40

.GP

J

GE

OL

AB

S.G

DT

2

/15

/11

3.0

3.5

3.0

31

22

45

33

49

Brown SANDY SILT with gravel (coralline), dry(fill)

Brown CLAY with some fine sand and gravel,very stiff, dry (alluvium)

grades to hard

grades to very stiff

Boring terminated at 16.5 feet

* Elevations estimated Grading Plan transmittedby Engineering Concepts, Inc. on October 26,2010.

95

112

103

ML

CL

16

19

18

20

21

LL=46PI=27

UC

Po

cke

t P

en

.(t

sf)

Date Started:

Date Completed:

Logged By:

Total Depth:

Work Order:

Dry

De

nsity

(pcf)

CME-75

4" Auger

140 lb. wt., 30 in. drop

Co

reR

eco

ve

ry (

%)

Laboratory

Pe

ne

tra

tio

nR

esis

tan

ce

(blo

ws/f

oo

t)

Sa

mp

le

Field

October 18, 2010

October 18, 2010

D. Gremminger

16.5 feet

5822-40

US

CS

De

pth

(fe

et)

5

10

15

20

25

Gra

ph

ic

Drill Rig:

Drilling Method:

Driving Energy:

Mo

istu

reC

on

ten

t (%

)Approximate Ground SurfaceElevation (feet MSL): 127 *

1

RQ

D (

%)

A - 1

Description

Water Level:

Oth

er

Te

sts

Log ofBoring

Plate

Not Encountered

BO

RIN

G_

LO

G

58

22

-40

.GP

J

GE

OL

AB

S.G

DT

2

/15

/11

GEOLABS, INC.


UNIVERSITY OF HAWAII WEST OAHU CAMPUSDRIVEWAY "B"

EWA, OAHU, HAWAII

3.5

2.5

>4.5

>4.5

35

22

70

88

20/2"Ref.

Brown CLAY with sand, very stiff, dry (alluvium)

grades with some weathered gravel

grades to very hard

Brown CLAY, very hard, dry (alluvium)


95

104

95

CL

CL

28

15

22

20

20

Po

cke

t P

en

.(t

sf)

Date Started:

Date Completed:

Logged By:

Total Depth:

Work Order:

Dry

De

nsity

(pcf)

CME-75

4" Auger


Co

reR

eco

ve

ry (

%)

Laboratory

Pe

ne

tra

tio

nR

esis

tan

ce

(blo

ws/f

oo

t)

Sa

mp

le

Field

October 18, 2010

October 18, 2010

D. Gremminger

15.7 feet

5822-40

US

CS

De

pth

(fe

et)

5

10

15

20

25

Gra

ph

ic

Drill Rig:

Drilling Method:

Driving Energy:

Mo

istu

reC

on

ten

t (%

)Approximate Ground SurfaceElevation (feet MSL): 127.5 *

2

RQ

D (

%)

A - 2

Description

Water Level:

Oth

er

Te

sts

Log ofBoring

Plate

Not Encountered

BO

RIN

G_

LO

G

58

22

-40

.GP

J

GE

OL

AB

S.G

DT

2

/15

/11

GEOLABS, INC.



EWA, OAHU, HAWAII

2.0

>4.5

>4.5

15

32

97

64

60/6"Ref.

Brown CLAY with some fine sand, stiff, dry(alluvium)

grades to hard

Brown CLAY, very hard, dry (alluvium)


82

90

82

CL

CL

14

16

17

18

17

LL=36PI=15

UC

Po

cke

t P

en

.(t

sf)

Date Started:

Date Completed:

Logged By:

Total Depth:

Work Order:

Dry

De

nsity

(pcf)

CME-75

4" Auger


Co

reR

eco

ve

ry (

%)

Laboratory

Pe

ne

tra

tio

nR

esis

tan

ce

(blo

ws/f

oo

t)

Sa

mp

le

Field

October 19, 2010

October 19, 2010

D. Gremminger

15.5 feet

5822-40

US

CS

De

pth

(fe

et)

5

10

15

20

25

Gra

ph

ic

Drill Rig:

Drilling Method:

Driving Energy:

Mo

istu

reC

on

ten

t (%


3

RQ

D (

%)

A - 3

Description

Water Level:

Oth

er

Te

sts

Log ofBoring

Plate

Not Encountered

BO

RIN

G_

LO

G

58

22

-40

.GP

J

GE

OL

AB

S.G

DT

2

/15

/11

GEOLABS, INC.



EWA, OAHU, HAWAII

13

27

73

54/6"Ref.

20/1"Ref.

Brown CLAY with some sand and gravel, stiff,dry (alluvium)

grades with gravel (coralline), very stiff

grades to very hard

Gray BOULDER (BASALTIC), very dense

Brown CLAY with some gravel, very hard, dry


89

110

84

CL

CL

14

4

12

3

17

Consol.

LL=47PI=28

UC

Po

cke

t P

en

.(t

sf)

Date Started:

Date Completed:

Logged By:

Total Depth:

Work Order:

Dry

De

nsity

(pcf)

CME-45

4" Auger


Co

reR

eco

ve

ry (

%)

Laboratory

Pe

ne

tra

tio

nR

esis

tan

ce

(blo

ws/f

oo

t)

Sa

mp

le

Field

October 19, 2010

October 19, 2010

D. Gremminger

15.6 feet

5822-40

US

CS

De

pth

(fe

et)

5

10

15

20

25

Gra

ph

ic

Drill Rig:

Drilling Method:

Driving Energy:

Mo

istu

reC

on

ten

t (%


4

RQ

D (

%)

A - 4

Description

Water Level:

Oth

er

Te

sts

Log ofBoring

Plate

Not Encountered

BO

RIN

G_

LO

G

58

22

-40

.GP

J

GE

OL

AB

S.G

DT

2

/15

/11

GEOLABS, INC.



EWA, OAHU, HAWAII

>4.590

62

60/6"Ref.

54/6"Ref.

60/5"Ref.

Brown CLAY with sand, very hard, dry (alluvium)

grades with gravel

Gray COBBLES AND BOULDERS (BASALTIC)

Brown CLAY with sand, very hard, dry (alluvium)


102

88

101

CL

CL

9

13

17

11

19

Po

cke

t P

en

.(t

sf)

Date Started:

Date Completed:

Logged By:

Total Depth:

Work Order:

Dry

De

nsity

(pcf)

CME-45

4" Auger


Co

reR

eco

ve

ry (

%)

Laboratory

Pe

ne

tra

tio

nR

esis

tan

ce

(blo

ws/f

oo

t)

Sa

mp

le

Field

October 19, 2010

October 19, 2010

D. Gremminger

15.9 feet

5822-40

US

CS

De

pth

(fe

et)

5

10

15

20

25

Gra

ph

ic

Drill Rig:

Drilling Method:

Driving Energy:

Mo

istu

reC

on

ten

t (%


5

RQ

D (

%)

A - 5

Description

Water Level:

Oth

er

Te

sts

Log ofBoring

Plate

Not Encountered

BO

RIN

G_

LO

G

58

22

-40

.GP

J

GE

OL

AB

S.G

DT

2

/15

/11

GEOLABS, INC.



EWA, OAHU, HAWAII

>4.5

1.5

4.0

57

18

13

33

51

Brown CLAY with sand and some gravel, hard,dry (alluvium)

grades to very stiff

grades to stiff

Brown CLAY, hard, dry (alluvium)


92

75

93

CL

CL

14

22

19

18

25

LL=43PI=17

Po

cke

t P

en

.(t

sf)

Date Started:

Date Completed:

Logged By:

Total Depth:

Work Order:

Dry

De

nsity

(pcf)

CME-75

4" Auger


Co

reR

eco

ve

ry (

%)

Laboratory

Pe

ne

tra

tio

nR

esis

tan

ce

(blo

ws/f

oo

t)

Sa

mp

le

Field

October 18, 2010

October 18, 2010

D. Gremminger

16.5 feet

5822-40

US

CS

De

pth

(fe

et)

5

10

15

20

25

Gra

ph

ic

Drill Rig:

Drilling Method:

Driving Energy:

Mo

istu

reC

on

ten

t (%


6

RQ

D (

%)

A - 6

Description

Water Level:

Oth

er

Te

sts

Log ofBoring

Plate

Not Encountered

BO

RIN

G_

LO

G

58

22

-40

.GP

J

GE

OL

AB

S.G

DT

2

/15

/11

GEOLABS, INC.



EWA, OAHU, HAWAII

4.0

0.5

1.0

>4.5

40

5

10

68

65/6"Ref.

Brown CLAY, hard, dry (alluvium)

grades to soft

Brown CLAY with sand and weathered gravel,stiff, dry (alluvium)

grades to very hard

Boring terminated at 16 feet

100

97

103

CL

CL

17

18

25

19

21

UC

Po

cke

t P

en

.(t

sf)

Date Started:

Date Completed:

Logged By:

Total Depth:

Work Order:

Dry

De

nsity

(pcf)

CME-75

4" Auger


Co

reR

eco

ve

ry (

%)

Laboratory

Pe

ne

tra

tio

nR

esis

tan

ce

(blo

ws/f

oo

t)

Sa

mp

le

Field

October 18, 2010

October 18, 2010

D. Gremminger

16 feet

5822-40

US

CS

De

pth

(fe

et)

5

10

15

20

25

Gra

ph

ic

Drill Rig:

Drilling Method:

Driving Energy:

Mo

istu

reC

on

ten

t (%


7

RQ

D (

%)

A - 7

Description

Water Level:

Oth

er

Te

sts

Log ofBoring

Plate

Not Encountered

BO

RIN

G_

LO

G

58

22

-40

.GP

J

GE

OL

AB

S.G

DT

2

/15

/11

GEOLABS, INC.



EWA, OAHU, HAWAII

APPENDIX B

W.O. 5822-40 GEOLABS, INC. FEBRUARY 2011 Page B-1 Hawaii ● California

A P P E N D I X B

Laboratory Testing

Moisture Content (ASTM D 2216) and Unit Weight (ASTM D 2937) determinations were performed on selected soil samples as an aid in the classification and evaluation of soil properties. The test results are presented on the Logs of Borings at the appropriate sample depths. Four one-inch Ring Swell tests were performed on relatively undisturbed and remolded samples to evaluate the swelling potential of the near-surface soils. The test results are summarized on Plate B-1. Three Atterberg Limits tests (ASTM D 4318) were performed on selected soil samples to evaluate their liquid and plastic limits and to aid in soil classification. The test results are summarized on the Logs of Borings at the appropriate sample depths. Graphic presentations of the test results are provided on Plate B-2. Four Unconfined Compression tests (ASTM D 2166) were performed on selected in-situ cohesive soil samples to evaluate the unconfined compressive strength of the soils. The test results are presented on the Logs of Borings at the appropriate sample depths, and graphic presentations of the test results and stress-strain curves are provided on Plates B-3 through B-6. One One-Dimensional Consolidation test (ASTM D 2435) was performed on a selected soil sample to evaluate the consolidation characteristics of the soils. Graphic presentation of the test results is provided on Plate B-7. Two laboratory California Bearing Ratio tests (ASTM D 1883) were performed on bulk samples of the near-surface soils to evaluate the pavement support characteristics of the soils. The test results are presented on Plates B-8 and B-9.

W.O. 5822-40 GEOLABS, INC. FEBRUARY 2011 PLATE B-1 Hawaii ● California

SUMMARY OF ONE-INCH RING SWELL TESTS

University of Hawaii West Oahu

Driveway “B” Ewa, Oahu, Hawaii

Moisture Contents Location

Depth

Soil Description

Dry Density Initial Air-Dried Final

Ring Swell

(feet) (pcf) (%) (%) (%) (%)

B-1 1.0 - 2.5 Brown Clay 83 18 14 38 3.6

B-2 1.0 - 2.5 Brown Clay 115 17 13 26 6.9

B-3* 1.0 - 2.5 Brown Clay 109 20 16 26 8.7

B-7 1.0 - 2.5 Brown Clay 95 19 15 32 4.4

NOTE: Samples tested were relatively undisturbed or remolded in 2.4-inch diameter by 1-inch high rings. They were air-dried overnight and then saturated for 24 hours under a surcharge pressure of 55 psf.

* Remolded

0

10

20

30

40

50

60

70

80

90

100

0 20 40 60 80 100 120

PIDepth (ft)Sample LL PL

Description

46

36

47

2.5-4.0

5.0-6.5

2.5-4.0

ML or OLCL-ML

CL or OL CH or OH

19

21

19

ATTERBERG LIMITS TEST RESULTS - ASTM D 4318

Brown clay (CL)

Brown clay

Brown clay (CL)

B - 2

MH or OH

27

15

28

LIQUID LIMIT

PLA

ST

ICIT

Y I

ND

EX

B-1

B-3

B-4

Plate

W.O. 5822-40

GEOTECHNICAL ENGINEERING

GEOLABS, INC.UNIVERSITY OF HAWAII WEST OAHU CAMPUS

DRIVEWAY "B"EWA, OAHU, HAWAII

G_

AT

TE

RB

ER

G

58

22

-40

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0

1

2

3

4

5

6

7

8

9

10

11

12

13

0 2 4 6 8 10

Location:

AXIAL STRAIN, %

5.0 - 6.5 feet

Description:

Depth:

CO

MP

RE

SS

IVE

ST

RE

SS

, ksf

B-1

Brown clay

Axial Strain at Failure (%):

Unconfined Compressive Strength (ksf):

Dry Density (pcf)

Moisture (%)

112.1

18.0

Sample Diameter (inches)

Sample Height (inches)

UNCONFINED COMPRESSION TEST - ASTM D 2166

Strain Rate (% / minute):

7.5

12.9

Test Date: 11/3/2010

5.470

2.389

B - 3

0.97

Plate

W.O. 5822-40




G_

UC

5

82

2-4

0.G

PJ

GE

OL

AB

S.G

DT

2

/15

/11

0

2

4

6

8

10

12

14

16

18

20

0 2 4 6 8 10

Location:

AXIAL STRAIN, %

5.0 - 6.5 feet

Description:

Depth:

CO

MP

RE

SS

IVE

ST

RE

SS

, ksf

B-3

Brown clay



Dry Density (pcf)

Moisture (%)

107.4

15.4





2.5

18.3


5.381

2.411

B - 4

0.85

Plate

W.O. 5822-40




G_

UC

5

82

2-4

0.G

PJ

GE

OL

AB

S.G

DT

2

/15

/11

0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0 2 4 6 8 10

Location:

AXIAL STRAIN, %

5.0 - 6.5 feet

Description:

Depth:

CO

MP

RE

SS

IVE

ST

RE

SS

, ksf

B-4

Brown clay



Dry Density (pcf)

Moisture (%)

109.9

12.1





2.5

2.0


5.354

2.407

B - 5

1.01

Plate

W.O. 5822-40




G_

UC

5

82

2-4

0.G

PJ

GE

OL

AB

S.G

DT

2

/15

/11

0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

1.6

1.8

2.0

0 2 4 6 8 10

Location:

AXIAL STRAIN, %

5.0 - 6.5 feet

Description:

Depth:

CO

MP

RE

SS

IVE

ST

RE

SS

, ksf

B-7

Brown clay



Dry Density (pcf)

Moisture (%)

97.2

24.7





5.6

1.9


5.468

2.389

B - 6

0.98

Plate

W.O. 5822-40




G_

UC

5

82

2-4

0.G

PJ

GE

OL

AB

S.G

DT

2

/15

/11

0

5

10

15

20

25

300.1 1 10 100

Initial Final

Dry Density, pcf:

35.7

0.7955

100.0

1.202 0.763

Degree of Saturation, %

Void Ratio

Sample Height, inches 1.0000

Water Content, %Sample: B-4

Depth: 1.0 - 2.5 feet

Description: Brown clay

Liquid Limit = Plasticity Index =

CO

NS

OLID

AT

ION

%

NORMAL PRESSURE, ksf

B - 7

CONSOLIDATION TEST - ASTM D 2435

13.8 24.4

110.588.4

N/A N/A

Plate

W.O. 5822-40




G_

CO

NS

OL

5

82

2-4

0.G

PJ

GE

OL

AB

S.G

DT

2

/15

/11

0

20

40

60

80

100

120

140

160

0 0.10 0.20 0.30 0.40 0.50 0.60

Depth:

Description:

117.1

Molding Moisture (%)

Hammer Wt. (lbs)

Hammer Drop (inches)

Sample:

Molding Dry Density (pcf)

16.7

Swell (%)

4.5

Bulk 1

Brown clay

6.39

Corr. CBR @ 0.1"

PENETRATION, inches

ST

RE

SS

, psi

Surface

Days Soaked 4

No. of Layers

CALIFORNIA BEARING RATIO - ASTM D 1883

No. of Blows

3/4 inch minus

10

5Aggregate

18

56

B - 8Plate

W.O. 5822-40




G_

CB

R

58

22

-40

.GP

J

GE

OL

AB

S.G

DT

2

/15

/11

0

20

40

60

80

100

120

140

160

0 0.10 0.20 0.30 0.40 0.50 0.60

Depth:

Description:

117.1


Hammer Wt. (lbs)


Sample:


16.7

Swell (%)

4.5

Bulk 1

Brown clay

6.39

Corr. CBR @ 0.1"

PENETRATION, inches

ST

RE

SS

, psi

Surface

Days Soaked 4

No. of Layers


No. of Blows

3/4 inch minus

10

5Aggregate

18

56

B - 8Plate

W.O. 5822-40




G_

CB

R

58

22

-40

.GP

J

GE

OL

AB

S.G

DT

2

/15

/11

0

10

20

30

40

50

60

70

80

0 0.10 0.20 0.30 0.40 0.50 0.60

Depth:

Description:

113.6


Hammer Wt. (lbs)


Sample:


17.7

Swell (%)

3.5

Bulk 2

Brown clay

5.43

Corr. CBR @ 0.1"

PENETRATION, inches

ST

RE

SS

, psi

Surface

Days Soaked 5

No. of Layers


No. of Blows

3/4 inch minus

10

5Aggregate

18

56

B - 9Plate

W.O. 5822-40




G_

CB

R

58

22

-40

.GP

J

GE

OL

AB

S.G

DT

2

/15

/11

0

10

20

30

40

50

60

70

80

0 0.10 0.20 0.30 0.40 0.50 0.60

Depth:

Description:

113.6


Hammer Wt. (lbs)


Sample:


17.7

Swell (%)

3.5

Bulk 2

Brown clay

5.43

Corr. CBR @ 0.1"

PENETRATION, inches

ST

RE

SS

, psi

Surface

Days Soaked 5

No. of Layers


No. of Blows

3/4 inch minus

10

5Aggregate

18

56

B - 9Plate

W.O. 5822-40




G_

CB

R

58

22

-40

.GP

J

GE

OL

AB

S.G

DT

2

/15

/11

Documents

HONOLULU RAIL TRANSIT PROJECT UH WEST O’AHU …hartdocs.honolulu.gov/docushare/dsweb/Get/Document-20607/9.1.3 … · about 0.5 to 2.5 feet deep at the existing ground surface. Because