Geotechnical Investigation - City of Albany, Oregon · Geotechnical Investigation ... encountered...

Geotechnical

Investigation

Albany Municipal Airport

Runway Extension & Apron Rehabilitation

Albany, Oregon

Prepared for:

Precision Approach Engineering, Inc.

Corvallis, Oregon

January 16, 2017

Foundation Engineering, Inc.

Professional Geotechnical Services

Albany Municipal Airport – Runway Extension & Apron Rehabilitation January 16, 2017

Geotechnical Investigation 1 Project 2161117

Albany, Oregon Precision Approach Engineering, Inc.

GEOTECHNICAL INVESTIGATION ALBANY MUNICIPAL AIRPORT

RUNWAY EXTENSION & APRON REHABILITATION

ALBANY, OREGON

BACKGROUND

The Albany Municipal Airport is planning improvements that will include extending

Runway 16-34 and rehabilitating the main apron west of the runway. We understand

the runway extension will incorporate the existing blast pad/overrun pavements on both

ends of the runway and will also include the construction of new connector taxiways

at both ends. The project location is shown on Figure 1A (Appendix). A layout of the

improvement areas is shown on Figures 2A through 4A (Appendix A).

Precision Approach Engineering, Inc. (PAE) is the prime engineering consultant and will

provide pavement and civil design services. PAE indicated the design for both the

runway extension and apron rehabilitation will be completed in 2017. Construction for

the apron rehabilitation is currently planned for 2017, while construction for the runway

extension is planned for 2018.

Foundation Engineering, Inc. was retained by PAE to perform the subsurface

investigation, conduct laboratory testing, and provide recommendations for subgrade

preparation and design parameters associated with the pavement improvements. We

have completed multiple investigations for different projects at the airport, which

include the Runway 16-34 rehabilitation project (circa 2010) and the access road

(i.e., Aviation Way SE) rehabilitation and north taxiways project (circa 2000).

Information from those investigations has been used to supplement the current work,

where applicable. The following sections summarize our work.

SITE CONDITIONS AND LOCAL GEOLOGY

The airport is located on a relatively flat alluvial plain, ±¾ mile east of the Willamette

River. Topographic relief is typically limited within the airport and the surrounding

area. A small drainage provides the southern boundary to the site and connects

Timber-Linn and Swan Lakes on the east and west sides of the airport. Vegetation

within the airport is primarily limited to short grass and scattered weeds.

Local geologic mapping (e.g., Wiley 2006) indicates the airport is underlain by

Willamette Silt and Linn Gravels. The Willamette Silt may contain mixtures of silt,

sandy silt, and silty clay. Our previous and current explorations at the airport

encountered mixtures of silt, clay, and sand at shallow depths, consistent with the

Willamette Silt. We have also completed deeper borings immediately north and west

of the airport for a previous project. Those borings encountered medium dense to

very dense gravel at depths ranging from ±0 to 15.5 feet.




FIELD EXPLORATION

Pavement Cores

Twelve pavement cores (C-1 through C-12) were completed at the site on

December 21, 2016, using a 5-inch diameter core drill and trailer-mounted drill rig.

C-1 was cored at the north end of Taxiway A, near the planned north taxiway and

runway extension. C-2 through C-10 were cored within the main apron and its

connecting taxilanes. C-11 was cored within the overrun pavement at the south end

of Runway 16-34 and C-12 was cored near the south end of Taxiway A (west of

C-11). The approximate core locations are shown on Figures 2A through 4A.

The exploration at C-10 was limited to the depth of the asphaltic concrete (AC) core

only. At the other explorations, the AC cores were removed and the base rock and

underlying subgrade was excavated using a solid-stem auger or hollow-barrel drilling

attachment. Drilling extended to maximum depths ranging from ±2 to 5 feet below

the paved surface. The core holes were logged to delineate the thickness of the AC

and the base rock, and to identify the subgrade conditions. The core hole logs are

included in Appendix B. Dynamic Cone Penetrometer (DCP) testing was performed

on the base rock and subgrade in each core hole. The DCP testing is described in a

subsequent section of this report.

Following the completion of the explorations, the core holes were backfilled with the

excavated materials, placed and compacted in thin lifts, and capped with granular fill

and AC cold patch.

Test Pits

Three test pits (TP-1 through TP-3) were excavated on December 21, 2016, using a

CASE 580 Super N backhoe. The test pits were dug to help document the soil

conditions across the site and to obtain bulk subgrade samples. TP-1 was dug north

of Taxiway A, near the planned connector for the north runway extension. TP-2 was

dug in a grass area adjacent to the main apron. TP-3 was dug where a connector

taxiway is planned near the south end or the runway. The approximate test pit

locations are shown on Figures 2A through 4A.

Each of the test pits extended to a depth of ±5 feet. The soil profiles were logged

and disturbed soil samples were retained for possible laboratory testing. Upon

completion, the excavated materials were placed back into the test pits and the

ground surface at each location was graded relatively smooth. The test pit logs are

included in Appendix B.




DISCUSSION OF SUBSURFACE CONDITIONS

The following sections provide a summary of the subsurface conditions encountered

in the explorations. More specific details are provided on the logs (Appendix B).

Photos of the pavement cores are also provided in Appendix B.

Pavement Cores

Pavement Section

The pavement cores encountered ±3 to 6 inches of AC. Consistent with the available

pavement inventory (e.g., Pavement Consultants, Inc. 2015), several of the cores

showed at least one previous overlay. The observed overlay thickness varied between

cores and typically included a non-woven paving fabric between the overlay and the

original wearing course. Additional details are provided in the logs and the pavement

core photos (Appendix B).

The AC is underlain by base rock that varies with location. At most of the explorations,

the base material consists of ±1.5 or 2-inch minus crushed gravel with varying sand

and silt content. Some of the cores (C-2, C-5, C-9, and C-12) encountered base

material consisting of unprocessed (i.e., uncrushed) gravel or sandy gravel. The

exploration at C-11 (completed in the south blast pad/overrun pavement) encountered

base material that included ±4 inches of AC millings and crushed gravel over an

additional ±4 inches of crushed gravel. Unified Soil Classification System (USCS)

Classifications for the base materials include GW, GP, and GP-GM.

The base rock thickness ranged from ±4 to 16 inches in the explorations. The total

thickness of the pavement sections (including the AC and base rock) ranged from

±9 to 20 inches. Pavement section thicknesses are summarized on Table 1B

(Appendix B).

Subgrade

The subgrade underlying the pavement section varies with location. Consistent with

previous investigations at the airport, most of the explorations encountered brown to

dark brown, low plasticity silty clay to silt with some clay, sand and gravel. These

soils were encountered in C-1, C-2, C-3, C-7, C-9, and C-11. Silty to sandy gravel was

encountered beneath the fine-grained subgrade in most of the above-noted locations at

depths ranging from ±2 to 3.5 feet. The gravel stratum was encountered directly

below the pavement section in C-12 and within a few inches below the pavement

section in C-8. The gravel stratum appears to be shallower towards the south end of

the airport.

Grey, medium to high plasticity clay or silty clay was encountered towards the middle

of the apron in C-4, C-5, and C-6. At these locations, the clay extended to the

maximum depth of the explorations (±5 feet). Similar soil was also encountered in C-8,

but to only a few inches below the pavement section. We also encountered grey, high

plasticity clay in one exploration (TP-2) completed for the north taxiways project in

2000. That test pit was located near the hangars at the northwest corner of the airport.




We interpreted the approximate limits of clay within the apron based on where it was

encountered in the recent explorations. The limits are represented as yellow dashed

lines in Figure 3A. However, the extent of the clay may be more variable than what is

shown in Figure 3A since it was also encountered further north during a previous

investigation.

Test Pits

The test pits encountered varying subgrade conditions, similar to the pavement

cores. TP-1 and TP-2 encountered dark brown, low plasticity silty clay or silt with

some clay, sand and gravel extending below the ground surface. This stratum was

encountered to ±3 feet in TP-1 and to ±1.5 feet in TP-2. The fine-grained soil is

followed by medium dense silty or sandy gravel that extended to the bottom of the

test pits (±5 feet). The fine-grained soil was not encountered in TP-3. Instead, the

exploration encountered silty to sandy gravel for the full depth of the exploration

(±5 feet). Medium to high plasticity clay, similar to that observed in C-4, C-5, and

C-6, was not encountered in the test pits.

Ground Water

Ground water infiltration was observed in the explorations completed near the north

and south ends of the runway. At the north end, moderate to rapid seepage was

observed in TP-1 at a depth of ±2.5 to 3 feet. Moderate seepage was also observed

in C-1 at ±3 feet. At the south end, moderate seepage was observed at ±3 feet in

TP-3 and C-11. Ground water was not observed in the other explorations. However,

the subgrade was typically moist at shallow depths across the site. Similar

conditions were observed during our previous explorations at the airport.

Given the close proximity of the airport to the surrounding Timber-Linn and Swan

Lakes, and the Willamette River further west, we anticipate the local ground water

remains relatively shallow throughout the year and closely corresponds to the water

level in the lakes. During periods of prolonged rainfall, perched ground water

conditions are also likely to develop at shallower depths where the low permeability

fine-grained soils (i.e., silts and clays) are present.

FIELD AND LABORATORY TESTING

DCP Testing

Dynamic Cone Penetrometer (DCP) testing was completed on the base rock and

subgrade within each of the core holes (except C-10). The DCP test consists of

driving the cone of the DCP apparatus into the soil and recording the penetration

versus blow count (mm/blow) as the DCP value. The Oregon Department of

Transportation (ODOT) Pavement Design Guide (2011) provides a correlation for

estimating the in-situ resilient modulus from results of the DCP testing. A summary

of the DCP test results and the correlated in-situ subgrade and base rock modulus

values are summarized in Table 1C (Appendix C).




In-situ modulus values ranging from ±7,739 to 22,565 psi were calculated for the

base rock, with an average value of ±16,674 psi. The relatively low modulus values

are likely due, in part, to thin base rock sections being influenced by the underlying

subgrade.

In-situ modulus values ranging from ±3,219 to 12,435 psi were calculated for the

subgrade, with an average value of ±5,131 psi. The FAA Airport Pavement Design

and Evaluation Circular (2016) recommends estimating the subgrade modulus based

on the following correlation with laboratory California Bearing Ratio (CBR) tests:

E = 1,500 x CBR

Based on the above equation, we back-calculated in-situ CBR values ranging from

±2.1 to 8.3 for the subgrade, with an average value of 3.4.

Significantly higher subgrade modulus values were observed where gravel was

encountered (C-8 and C-12). At those locations, the calculated modulus value

ranged from ±6,309 to 12,435 psi, with back-calculated CBR values ranging from

4.6 to 8.3. The remaining explorations with predominantly silt or clay subgrade had

calculated modulus values ranging from ±3,219 to 6,309 psi, and back-calculated

CBR values ranging from 2.1 to 4.2 (with an average value of 2.7).

Laboratory Testing

Index Tests

The laboratory work included natural water content determinations, Atterberg limits

tests, and mechanical sieve and hydrometer analyses to classify the soils and

estimate their overall engineering properties. The test results are summarized on

Table 2C and Figures 1C through 6C (Appendix C).

The Atterberg limits tests were completed on two bulk samples from TP-1 and TP-2

(S-1-1 and S-2-1) and four samples from the pavement cores (C-3-2, C-5-2, C-6-2,

and C-11-2). The samples were selected to represent the range in plasticity observed

in the subgrade soils. Most of the test results fall on or near the dividing line between

USCS classifications CL and ML (i.e., low plasticity clay or silt). Therefore, we used

a dual classification to characterize most of the subgrade. Sample C-6-2 (from core

hole C-6) was an outlier, with USCS classification CH (i.e., high plasticity clay).

The Atterberg limits results are generally consistent with the range of values from

previous projects at the airport. Figure 1C provides a summary of the Atterberg

limits test results from the current project and previous projects. As noted in

Figure 1C, most of the test samples fall close to the dividing line between CL and

ML soils. Two samples, C-6-2 from the current study and S-2-2 from the Access

Road & Taxiways project (2000), have significantly higher plasticity and are classified

as CH soils.

Sieve and hydrometer gradation curves were completed on the bulk samples from

TP-1 and TP-2 (Figures 2C and 3C). The results are consistent with the Atterberg

limits, indicating primarily silt and clay-sized particle with some sand and gravel. A




sieve analysis on the bulk sample from TP-3 (S-3-1) indicated the subgrade at that

location consists of primarily gravel with some sand and silt, and a USCS

classification of GM.

Sieve analyses were also completed on two samples of the base rock from the apron

at C-4 and C-5 (samples C-4-1 and C-5-1). Both samples contain primarily

gravel-sized particles with fines contents ranging from ±5.8 to 7 percent, and

resulting USCS classification of GW-GM.

Moisture-Density and CBR Testing

Moisture-density curves (ASTM D698) were developed for bulk samples obtained

from TP-1 (S-1-1) and TP-2 (S-2-1). The individual test results are summarized in

Figures 7C and 9C (Appendix C). The results are also summarized in Table 3C

(Appendix C). The test results indicate a maximum dry density of 107.7 pcf at an

optimum moisture content of 16.2% for S-1-1, and a maximum dry density of

106.0 pcf at an optimum moisture content of 14.2% for S-2-1. Both

moisture-density test curves were modified using an oversize correction factor since

the samples included greater than 5% gravel content.

California Bearing Ratio (CBR, ASTM D1883) tests were completed on samples S-1-1

and S-2-1 using the results from the compaction tests. The individual CBR results

are summarized in Figures 8C and 10C (Appendix C). The results are also

summarized in Table 3C. At 95% relative compaction (with oversize correction), the

test results indicate a CBR value of 8.9 for sample S-1-1 and a CBR value of 4.3 for

S-2-1.

The test results indicate a wide range in CBR values for similar soils. The CBR value

of 8.9 for S-1-1 is high for predominantly silt and clay soils. Therefore, we believe

the gravel in sample S-1-1 (±23.7% gravel; see Figure 2C) likely skewed the results.

A CBR value of 4.3 for sample S-2-1 is more typical for these soils.

Moisture-density and CBR test results for the current project and previous projects

at the airport are summarized in Table 3C. Additional scattered in the CBR values is

apparent from Table 3C. Some of this additional scatter can be attributed to the

varying soil conditions. For example, the lowest CBR value of 1.4 was from a test

complete on a sample of high plasticity clay (USCS classification CH). We note

consistent CBR values of 4.3 for two samples of silty clay or clayey silt (USCS

classification CL). Additional discussion and recommendations for design CBR values

are provided in the following section.

DISCUSSION OF GEOTECHNICAL CONSIDERATIONS AND DESIGN REQUIREMENTS

The following sections discuss geotechnical considerations and recommendations for

the proposed runway extension and apron rehabilitation. We anticipate PAE will

evaluate options that include full depth reconstruction or overlay of the existing apron

and the overrun pavements where the runway will be extended. New pavement

sections will be required to provide connector taxiways between the lengthened

runway ends and Taxiway A.




Discussion of Subgrade Conditions

The pavement subgrade varies across the site, but typically consists of silty clay

and/or silt with some clay, sand and gravel. Corresponding USCS classifications

range from CL to ML. Appendix A of the 2016 FAA Airport Pavement Design and

Evaluation Advisory Circular (AC 150/5320-6F) indicates that soils designated as CL

or ML are “fair to good” as a foundation material when not subject to frost action.

Frost-susceptibility is discussed in a subsequent section of this report.

A portion of the apron is underlain by high plasticity clay with corresponding USCS

classification CH. The FAA Pavement Advisory (2016) characterizes this soil as

“poor to very poor”. The estimated limits of the high plasticity clay are shown in

Figure 3A.

Silty gravel (with corresponding USCS classification GM) was encountered at shallow

depths in some of the explorations. The FAA Pavement Advisory (2016)

characterizes these soils as “good” as a foundation material. The gravel may be

shallowest towards the south end of the airport. However, the depth to gravel

appears to vary across the site. Therefore, we do not recommend predicating any

portion of the pavement design on the gravel subgrade.

Parameters for Pavement Overlay

If rehabilitation of the apron includes pavement overlay (or mill and inlay), we

recommend the following design parameters:

Subgrade

If pavement overlay is planned, the subgrade will remain in its present condition.

Therefore, the results of the DCP testing are most suitable for evaluating the

subgrade. Excluding the DCP test on gravel subgrade, which was only encountered

at two locations, the tests indicated a mean resilient modulus of 4,116 psi (CBR

value of 2.7) with a standard deviation of 900 psi. The mean minus one standard

deviation is 3,216 psi, which correlates to a CBR value of ±2.1. Therefore, we

recommend assuming a CBR value of 2.1 for design. This value is recommended

across the site, regardless if the subgrade is classified as CL/ML or CH.

Base Rock

The existing base rock consists of crushed and uncrushed gravel with varying silt

and sand content. The DCP tests indicated an average base rock modulus of

±16,674 psi. Default modulus values for unreinforced base material in FAARFIELD

are significantly greater, ranging from 40,000 psi (P-154) to 70,000 psi (P-209). We

anticipate the relatively low modulus values correlated from the DCP testing are due

to the quality of the existing base rock and the relatively thin base rock section over

weak subgrade. We recommend assuming a base rock modulus of 15,000 psi to

evaluate a pavement overlay.




Existing AC

We recommend assuming a modulus value of 200,000 psi to represent the existing

AC to evaluate the pavement overlay. A modulus value of 200,000 psi is consistent

with the FAARFIELD default for existing surface AC that will be overlain.

If all or portions of the existing pavements remain in place, methods should be

evaluated to mitigate the risk of existing cracks propagating through the new AC.

Mitigation techniques typically include milling the existing AC, placing fabric and

sealants over the existing AC prior to paving, and/or providing a relatively thick

overlay. When milling to repair existing pavement damage, FAA requires leaving at

least 2 inches of AC in place unless the entire section is removed.

Subgrade Preparation and Parameters for New Pavement Design

For new pavements and/or full-depth reconstruction, the appropriate subgrade

parameters and preparation will depend, in part, on location since the subgrade varies

across the airport. As discussed above, three general soil types were identified at

the subgrade elevation, which include: low plasticity silty clay or silt with some clay

(CL or ML soils), medium to high plasticity clay (CH soil), and silty gravel (GM soil).

The extent of the silty gravel at the subgrade elevation is variable and appears to be

limited. Therefore, we recommend the pavement design be predicated on either the

CL/ML soil or the CH soil. Recommendations for these two soil types is provided

below.

Low Plasticity Silty Clay to Silt, some Clay (CL/ML Soil)

Low plasticity silty clay to silt, some clay (CL/ML soil) was encountered in most of

the explorations within the improvement area, except the mid-section of the apron

(see Figure 3A). Therefore, the recommended soil parameters and preparation

described below should be suitable for most of the planned pavement improvements.

The laboratory testing indicated a range of CBR values for the CL/ML soil that varied

for reasons discussed above. A CBR value of 4.3 (indicated by two test results) is

within the typical range for these soils. Therefore, we recommend assuming a design

CBR value of 4 for the CL/ML subgrade soils where new pavements and/or full-depth

reconstruction is planned. This is consistent with the recommended CBR value for

the Runway 16-34 Rehabilitation project completed in 2010.

The recommended CBR value assumes the subgrade will be moisture-conditioned, as

required, and compacted to a minimum of 95% relative compaction (based on the

maximum dry density of ASTM D698) prior to placing subbase and base rock.

Multiple moisture-density curves and careful inspection of the soils will be required

to evaluate the relative compaction of the subgrade because of the varying

moisture-density test results that have been observed. This includes allowing for an

over-size correction where the subgrade has greater than 5% gravel content.




The subgrade is moisture-sensitive. Therefore, we recommend compacting it at or

slightly dry of optimum moisture to reduce the risks of pumping. The prepared

subgrade should be backfilled with base rock or subbase as soon as practical to limit

moisture fluctuations (i.e., wetting or drying).

Medium to High Plasticity Clay (CH Soil)

Medium to high plasticity clay (CH soil) was encountered near the mid-section of the

apron (see Figure 3A). Laboratory test results from a previous project indicated a

CBR value of 1.4 for this soil (see Table 3C). In-situ DCP tests during the current

investigation indicated subgrade modulus values ranging from ±3,564 to 4,441 psi

(i.e., CBR values ranging from ±2.4 to 3.0). Based on these results, we recommend

assuming a design CBR value no greater than 2 for this material for designing new

pavements.

The FAA Pavement Advisory (AC 150/5320-6E) indicates a CBR of 3 (i.e., subgrade

modulus of 4,500 psi) is the lowest value recommended for design of new

pavements. For subgrade with a CBR below 3, subgrade stabilization or other means

to improve the CBR value is recommended. FAA also requires stabilization for

subgrade with swell greater than 3% and high potential for moisture fluctuation. The

previous CBR test on CH soil from the airport indicated a swell of at least 3.4%.

Options available for subgrade improvement include mechanical and chemical

stabilization. Given the relatively limited treatment area, which includes only a

portion of the apron, we anticipate the most cost-effective solution will be partial

overexcavation and replacement where the clay is present. For completeness,

additional options are also discussed briefly below.

Mechanical Stabilization. Mechanical stabilization typically includes overexcavating

and replacing soft soils, and bridging the soft areas with a thick lift of large,

open-graded aggregate. The clay subgrade encountered in the explorations was

typically medium stiff to stiff. Therefore, we do not anticipate needing an

overly-thick layer of stabilization material to facilitate construction. Rather, the

stabilization layer would be used to mitigate the long-term pavement performance

due to low CBR value and swell potential and the clay.

If overexcavation and replacement is selected, we believe it would be reasonable to

assume a nominal overexcavation and replacement depth 1 foot below the planned

subgrade elevation. This will provide a suitable treatment depth to mitigate swelling

soils per FAA requirements and provide a working platform for placing new base rock

and subbase. The excavation should extend to medium stiff to stiff, relatively

undisturbed subgrade and the overexcavated material should be replaced with

granular material (e.g., additional base rock or subbase) underlain by a separation

geotextile. If these two requirements are met, it is our opinion a CBR of 3 may be

used for flexible pavement design to represent the combination of imported fill within

the overexcavated zone and the underlying native soils.




Geogrid reinforcement could also be used to improve the strength of the pavement

section to compensate for the low subgrade strength. The relative improvement is

highly dependent on the selected geogrid and may be proprietary to particular geogrid

manufacturers. Therefore, the design of a geogrid-reinforced pavement section

would require consultation and analysis from selected geogrid manufacturer(s).

Chemical Stabilization. Chemical stabilization includes mixing cement, lime, or other

additives into the subgrade to improve its strength. Cement stabilization would

provide an additional, stabilized layer within the pavement section. It also would

provide a working surface to facilitate placement of the granular base course. If this

option is desirable, additional testing would be required to evaluate the required

application rate to meet durability requirements, as well as a design CBR value for

the treated layer. For preliminary evaluation of costs, we recommend assuming a

nominal treatment depth of 12 inches and a cement application rate of ±12% by

weight based on the subgrade soils at the site. The underlying subgrade (below the

treatment depth) should remain relatively undisturbed.

FAA’s recommends selecting the design CBR value for chemically-treated subgrade

as one standard deviation below the mean CBR value from the laboratory testing.

For the underlying, untreated and uncompacted subgrade, we recommend assuming

a CBR of 2.

Frost Considerations

Most of the subgrade consists of silty clay or silt with some clay (CL to ML soil) with

plasticity index (PI) values typically less than 12. This material corresponds to a FAA

frost group classification of FG-4, suggesting most of the subgrade is highly

frost-susceptible. The high plasticity clay (CH soil) that was encountered in the

mid-section of the apron has a corresponding frost group classification of FG-3.

Complete mitigation of the risk of detrimental frost heave requires overexcavation and

replacement of the soils below the depth of frost penetration. The local building code

for Linn County indicates a frost penetration depth of ±12 inches in the vicinity of the

airport. Given the limited frost depth, we expect frost mitigation will not be an issue

in the design of new pavements.

Site Drainage

The 2016 FAA Pavement Advisory (AC 150/5320 6E), Appendix A, indicates soil

classified as CL or ML can have drainage characteristics ranging from fair to

practically impervious. Soil classified as CH generally has very low permeability.

The 2013 FAA Surface Drainage Design Advisory Circular (AC 150/5320-5D),

Figure G-3, suggests a coefficient of permeability, k, for these soils in the range of

10-7 cm/sec to 10-10 cm/sec, which corresponds to practically impermeable soil.

Given the high clay content of the subgrade, we recommend assuming a k value no

higher than 10-8 cm/sec for evaluating drainage alternatives.




Construction Considerations

Site Stripping

Where new pavements are planned (i.e., connector taxiways), we recommend

assuming a nominal stripping depth of 4 inches to remove sod, roots, and/or other

organics.

Construction Timing

The airport site is relatively flat and underlain by low permeability soils. As such,

rainfall perches on the site in the wet winter and spring months. The perched water

typically disappears in the summer months, where the soil is exposed to dry weather

(i.e., outside existing paved areas). However, it has been our experience that

subgrade covered by existing pavements can remain wet of optimum year-round.

Therefore, where complete reconstruction is planned, wet subgrade should be

anticipated beneath the existing pavements regardless of the construction season.

As such, the construction schedule should include ample time to aerate and

moisture-condition the soils prior to compaction. We anticipate

moisture-conditioning will require ripping and aerating the soils to a depth of

±12 inches.

We recommend completing the earthwork during the dry summer months (typically

July through September), when it should be practical to adjust the moisture content

of the soil to near optimum and compact the subgrade. The contractor may still

experience pumping problems and have difficulty achieving adequate compaction in

the summer if the soils have not adequately dried.

If the construction schedule does not allow enough time for soil aeration,

overexcavation and replacement of wet soils should be anticipated. Where wet soils

are overexcavated, a thickened subbase and/or base rock section over a separation

geotextile is typically required to protect the moisture-sensitive soils and limit the risk

of subgrade pumping from repeated construction traffic. A fill thickness of ±18 to

24 inches is typical required. The actual fill thickness will depend on the stiffness

and moisture content of the exposed subgrade.

Reclamation of Existing Materials

The existing base materials are variable and likely will not meet the requirements for

re-use as P-209 (base course). However, it may be possible to re-use the base

material as P-154 (subbase course) for reconstructed pavement sections if it is mixed

with reclaimed AC (ground to 3-inch minus particle size) or combined with cleaner

imported granular fill. AC millings and reclaimed base rock could also be used in

areas where overexcavation of poor subgrade is required (e.g., CH soil in the apron).

Fill Materials and Compaction

The base rock for new pavements should consist of 1 or ¾-inch minus, clean

(i.e., less than 5% passing the No. 200 sieve), well-graded, crushed gravel or rock

conforming to FAA P-209 requirements. Subbase material should consist of




free-draining sand, gravel, rock, asphalt grindings, or mixtures of the above that

conform to FAA P-154 requirements and are free of plastic clay and organic matter.

All fill should be placed in level lifts not exceeding 12 inches and compacted to a

minimum of 95% relative compaction. The maximum dry density of ASTM D698

should be used as the standard for estimating relative compaction of the fill. The

moisture content of the fill and subgrade should be adjusted to within ±2% of its

optimum value prior to compaction.

Imported granular fill will compact most efficiently with a smooth-drum, vibratory

roller. Efficient compaction of fine-grained subgrade (where practical) will typically

require the use of a tamping foot or kneading roller. Field density tests should be

run frequently to confirm adequate compaction of the base rock, subbase, and

subgrade. Adequate compaction of fill materials, which are too coarse or variable

for density testing, should be evaluated by observation of the compaction method

and proof-rolling with a loaded dump truck or other approved heavy construction

vehicle.

DESIGN REVIEW/CONSTRUCTION OBSERVATION/TESTING

We should be provided the opportunity to review all drawings and specifications that

pertain to site preparation and fill placement. Site preparation for new pavements

will require field confirmation of the subgrade conditions. Mitigation of pumping

subgrade and fill will also require engineering review and judgment. That judgment

should be provided by one of our representatives. We recommend we be retained

to provide the necessary construction observations.

VARIATION OF SUBSURFACE CONDITIONS, USE OF THIS REPORT AND WARRANTY

The analysis, conclusions, and recommendations contained herein assume the soil

profiles encountered in the pavement cores and test pits are representative of the

site conditions. The above recommendations assume we will have the opportunity

to review final drawings and be present during construction to confirm the assumed

subgrade conditions. No changes in the enclosed recommendations should be made

without our approval. We will assume no responsibility or liability for any engineering

judgment, inspection, or testing performed by others.

This report was prepared for the exclusive use of Precision Approach

Engineering, Inc. and their design consultants for the Albany Municipal Airport –

Runway Extension and Apron Rehabilitation project in Albany, Oregon. Information

contained herein should not be used for other sites or for unanticipated construction

without our written consent. This report is intended for planning and design

purposes. Contractors using this information to estimate construction quantities or

costs do so at their own risk. Our services do not include any survey or assessment

of potential surface contamination or contamination of the soil or ground water by

hazardous or toxic materials. We assume those services, if needed, have been

completed by others.

Our work was done in accordance with generally accepted soil and foundation

engineering practices. No other warranty, expressed or implied, is made.




REFERENCES

ASTM, 2014, Standard Test Methods for CBR (California Bearing Ratio) of Laboratory-Compacted Soil: American Society for Testing and Materials (ASTM), Standard D1883, vol. 04.08.

ASTM, 2012, Standard Tests Methods for Laboratory Compaction Characteristics of Soil Using Standard Effort (12,400ft-lbf/ft3 (600kN-m/m3)): American Society for Testing and Materials (ASTM), Standard D698, vol. 04.08.

FAA, 2016, Airport Pavement Design and Evaluation Advisory Circular: AC No. 150/5320-6F, Federal Aviation Administration.

FAA, 2013, Subsurface Drainage Design Advisory Circular: AC No. 150/5320-5D, Federal Aviation Administration.

FAA, 2014, Standards for Specifying Construction of Airports Advisory Circular:

AC No. 150/5370-10G, Federal Aviation Administration.

ODOT, 2011, ODOT Pavement Design Guide, Oregon Department of Transportation

(ODOT), Pavement Services Unit.

Wiley, T.J., 2006, Preliminary Geologic Map of the Albany Quadrangle, Linn, Marion

and Benton Counties, Oregon: Oregon Department of Geology and Mineral

Industries, Open-File Report O-06-26.

Appendix A

Figures



2161117

Source: ODOT City Maps Database

SITE

Albany

North Albany

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FIGURE NO.

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DWN.

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APPR.

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DATE

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FILE NAME:

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820 NW CORNELL AVENUE

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BUS. (541) 757-7645 FAX (541) 757-7650

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CORVALLIS, OR 97330-4517

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FOUNDATION ENGINEERING INC.

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PROFESSIONAL GEOTECHNICAL SERVICES

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VICINITY MAP

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ALBANY MUNICIPAL AIRPORT

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Albany, Oregon

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1A

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Dec. 2016

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SITE LAYOUT AND EXPLORATIONS - NORTH RUNWAY

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NOTES: 1. TEST PIT AND PAVEMENT CORE LOCATIONS WERE ESTABLISHED USING VISUAL REFERENCES AND ARE APPROXIMATE. 2. SEE REPORT FOR A DISCUSSION OF SUBSURFACE CONDITIONS. 3. AERIAL PHOTO FOR BASE MAP WAS OBTAINED FROM GOOGLE EARTH.

2161117

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limits of CH Clay

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SITE LAYOUT AND EXPLORATIONS - SOUTH RUNWAY

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Appendix B Test Pit and Core Hole Logs and Core Photos

ProfessionalGeotechnicalServices


S-1-1

S-1-2

SILT, some clay, sand, and gravel (ML); dark brown, lowplasticity, moist to wet, medium stiff, fine to coarse sand, fine tocoarse subrounded gravel, (alluvium).

Silty GRAVEL, some sand (GM); grey to brown, low plasticity silt,wet, medium dense, fine to coarse sand, fine to coarsesubrounded gravel, (alluvium).

BOTTOM OF EXPLORATION

Surface: Short grass.

Fine roots extend to ±9 inches.

Moderate seepage at ±2.5 feet.

Rapid seepage at ±3 feet.

Albany, Oregon

N/A (Approx.)

Project No.:

Surface Elevation:

Date of Test Pit:

2161117 Test Pit Log: TP-1



December 21, 2016

1

2

3

4

5

Soil and Rock Description

Dep

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Comments

S-2-1

S-2-2

Silty CLAY, some sand and gravel (CL); dark brown, lowplasticity, moist, medium stiff, fine to coarse sand, fine to coarsesubrounded gravel, (alluvium).

Sandy GRAVEL, trace to some silt (GP-GM); brown to grey,damp, medium dense, fine to coarse sand, fine to coarsesubrounded gravel, (alluvium).


Surface: Short grass.


No seepage or ground waterencountered to the limit of excavation.

Albany, Oregon

N/A (Approx.)

Project No.:

Surface Elevation:

Date of Test Pit:




December 21, 2016

1

2

3

4

5


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S-3-1

S-3-2

Silty, sandy GRAVEL (GM); grey to brown, low plasticity silt,moist, medium dense, fine to coarse sand, fine to coarsesubrounded gravel, (alluvium).

Sandy GRAVEL, scattered cobbles (GP); grey, wet, mediumdense, fine to coarse sand, fine to coarse subrounded gravel,subrounded cobbles up to ±6 inch diameter, (alluvium).


Surface: Short grass and weeds.


Moderate seepage at ±3 feet.

Albany, Oregon

N/A (Approx.)

Project No.:

Surface Elevation:

Date of Test Pit:




December 21, 2016

1

2

3

4

5


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Comments

C-1-1

C-1-2

ASPHALTIC CONCRETE (±4 inches).

CRUSHED GRAVEL (GW) (±16 inches); grey, damp, dense,±1½-inch minus, angular to subrounded gravel, (base rock).

Sandy SILT, some clay (ML); dark brown, low plasticity, moist towet, soft to medium stiff, fine to coarse sand, (alluvium).


Core includes ±2-inch overlay overoriginal wearing course.


N/A (Approx.)

Project No.:

Surface Elevation:

Date:

2161117 Core Hole Log: C- 1


Runway Extension & Apron Rehabilitation Albany, OregonDecember 21, 2016

1

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Comments

C-2-1

C-2-2

C-2-3


GRAVEL (GP) (±4 inches); grey, damp, medium dense, coarsesubrounded gravel, (base rock).Silty CLAY to SILT, some clay, sand, and gravel (CL to ML); darkbrown, low plasticity, moist, medium stiff, fine sand, (alluvium).

Silty GRAVEL, some sand (GM); grey to brown, low plasticity silt,moist, medium dense, fine to coarse sand, fine to coarsesubrounded gravel, (alluvium).

Sandy GRAVEL, trace silt (GP); grey, damp to moist, dense, fineto coarse sand, fine to coarse subrounded gravel, (alluvium).


Core includes 3 lifts: 2.25-inch withgeotextile fabric/1.75-inch/2-inch


N/A (Approx.)

Project No.:

Surface Elevation:

Date:




1

2

3

4

5


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#

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Comments

C-3-1

C-3-2

C-3-3


CRUSHED GRAVEL, some sand and silt (GW-GM) (±11 inches);grey to brown, damp, ±1½-inch minus, (base rock).

Silty CLAY to SILT, some clay, sand, and gravel (CL to ML); darkbrown, low plasticity, moist, medium stiff, fine to coarse sand,fine subrounded gravel, (alluvium).

Silty GRAVEL, some sand (GM); grey to brown, low plasticity silt,moist, medium dense to dense, fine to coarse sand, fine tocoarse subrounded gravel, (alluvium).


Cored on surface crack that extendedthrough the core. ±1.75-inch overlaywith geotextile fabric over originalwearing course.

Base rock is minimally processed withfew fractured faces.


N/A (Approx.)

Project No.:

Surface Elevation:

Date:




1

2

3

4

5


Dep

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#

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Comments

C-4-1

C-4-2


CRUSHED GRAVEL, some sand and silt (GW-GM) (±9 inches);grey, damp, dense, ±1½-inch minus, angular to subroundedgravel, (base rock).CLAY (CH); grey, high plasticity, moist, medium stiff, (alluvium).


Irregular surface on the bottom of thecore. Reported AC thickness of5 inches is the thickest portion of thecore.


N/A (Approx.)

Project No.:

Surface Elevation:

Date:




1

2

3

4

5


Dep

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#

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Comments

C-5-1

C-5-2


Sandy GRAVEL, some silt (GW-GM) (±6 inches); grey to brown,moist, medium dense, fine to coarse sand, fine to coarsesubangular to subrounded gravel, (base rock).Silty CLAY (CL to ML); grey, medium plasticity, moist, mediumstiff to stiff, (alluvium).


Core includes ±1.75-inch overlay withgeotextile fabric over original wearingcourse.


N/A (Approx.)

Project No.:

Surface Elevation:

Date:




1

2

3

4

5


Dep

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Comments

C-6-1

C-6-2


CRUSHED GRAVEL (GW) (±8 inches); grey, damp to moist,dense, ±1½-inch minus, angular to subrounded gravel, (baserock).CLAY (CH); grey, high plasticity, moist, stiff, (alluvium).


Core includes ±2.5-inch overlay withgeotextile fabric over original wearingcourse. Lower AC lift is fractured.


N/A (Approx.)

Project No.:

Surface Elevation:

Date:




1

2

3

4

5


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Comments

C-7-1

C-7-2

ASPHALTIC CONCRETE (±3.75 inches).CRUSHED GRAVEL, some sand (GW) (±13.25 inches); grey,damp, dense, ±1-inch minus, angular to subrounded gravel,(base rock).

Gravelly SILT, some clay (ML); brown, low plasticity, moist,medium stiff, fine subrounded gravel, (alluvium).

Silty GRAVEL, some sand (GM); grey to brown, low plasticity silt,moist, medium dense, fine to coarse sand, fine to coarsesubrounded gravel, (alluvium).

BOTTOM OF EXPLORATIONNo seepage or ground waterencountered to the limit of excavation.

N/A (Approx.)

Project No.:

Surface Elevation:

Date:




1

2

3

4

5


Dep

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#

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C-8-1

C-8-2C-8-3

ASPHALTIC CONCRETE (±4.5 inches).

CRUSHED GRAVEL, some sand (GW) (±4.5 inches); grey, damp,medium dense, ±2-inch minus, angular to subrounded gravel,(base rock).CLAY, trace gravel (CH); grey, high plasticity, moist, stiff,(alluvium).Silty GRAVEL, some sand (GM); grey to brown, low plasticity silt,moist, dense, fine to coarse sand, fine to coarse subroundedgravel, (alluvium).


Core includes ±½-inch overlay withgeotextile fabric. Irregular surface onthe bottom of the core. Reported ACthickness of ±4.5 inches is the thickestportion of the core.

Practical drilling refusal at ±2.5 feet oncoarse gravel or cobble.


N/A (Approx.)

Project No.:

Surface Elevation:

Date:




1

2

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5


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C-9-1

C-9-2


Sandy GRAVEL (GP) (±7.5 inches); grey, damp, dense, fine tocoarse sand, fine to coarse subrounded gravel, (base rock).

SILT, some clay, trace gravel (ML); dark brown, low plasticity,moist, medium stiff, fine subrounded gravel, (alluvium).

Silty GRAVEL, some sand (GM); grey to brown, low plasticity silt,moist, medium dense, fine to coarse sand, fine to coarsesubrounded gravel, (alluvium).BOTTOM OF EXPLORATION


Practical drilling refusal at ±3 feet oncoarse gravel or cobble.No seepage or ground waterencountered to the limit of excavation.

N/A (Approx.)

Project No.:

Surface Elevation:

Date:




1

2

3

4

5


Dep

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Fee

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ASPHALTIC CONCRETE (±3 inches).BOTTOM OF EXPLORATION

Limited to AC core only.

N/A (Approx.)

Project No.:

Surface Elevation:

Date:

2161117 Core Hole Log: C-10



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C-11-1

C-11-2

C-11-3


CRUSHED GRAVEL and ASPHALTIC CONCRETEGRINDINGS, trace sand and silt (GW) (±4 inches); grey to black,damp, dense, ±2-inch minus, angular to subangular gravel, (baserock).CRUSHED GRAVEL, trace silt and sand (GP) (±4 inches); grey,damp, dense, ±1½-inch minus, angular to subrounded gravel,(subbase).Silty CLAY to SILT, some clay and gravel (CL to ML); darkbrown, low to medium plasticity, moist to wet, medium stiff tostiff, fine subrounded gravel, (alluvium).

Clayey GRAVEL, some silt and sand (GC); brown, mediumplasticity clay, wet, medium dense, fine to coarse sand, fine tocoarse subrounded gravel, (alluvium).



N/A (Approx.)

Project No.:

Surface Elevation:

Date:




1

2

3

4

5


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Comments

C-12-1

C-12-2


Sandy GRAVEL, trace silt (GP) (±5 inches); grey to brown, dampto moist, dense, fine to coarse sand, fine to coarse angular tosubrounded gravel, (base rock).Sandy GRAVEL, some silt (GW-GM); grey to brown, lowplasticity silt, moist, dense, fine to coarse sand, fine to coarsesubangular to subrounded gravel, (possible fill).



Practical drilling refusal at ±2 feet oncoarse gravel or cobble.No seepage or ground waterencountered to the limit of excavation.

N/A (Approx.)

Project No.:

Surface Elevation:

Date:




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2

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4

5


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Foundation Engineering, Inc. Albany Municipal Airport Runway Extension & Apron Rehabilitation Project 2161117

Photo 1. Pavement Core C-1





Project 2161117

Table 1B. Summary of Pavement Thicknesses

1Exploration 1Location 2Asphaltic Concrete

Thickness

(in.)

3,4,5Base Rock

Thickness

(in.)

Total

Pavement Section

(in.)

C-1 Taxiway A (north) 4 16 20

C-2 Apron at north

Taxiway A access 6 4 10

C-3 Apron 4 11 15

C-4 Apron 5 9 14

C-5 Apron 5 6 11

C-6 Apron 4 8 12

C-7 Apron 3.75 13.25 17

C-8 Apron at A3 4.5 4.5 9

C-9 Apron 6 7.5 13.5

4C-10 Taxilane south of

apron 3 - -

5C-11 South blast pad/

overrun pavement 4 4/4 12

C-12 Taxiway A (south) 5 5 10

Notes: 1. See Figure 2A for approximate pavement core locations.

2. Pavement core photos are included in Appendix B.

3. Base rock varied in the explorations, typically consisting of either 1.5 to 2-inch minus

CRUSHED GRAVEL or sandy GRAVEL. USCS Classifications include GW, GP and

GP-GM.

4. Exploration C-10 was limited to the asphaltic concrete (AC) core only and did not

measure the entire pavement section.

5. Exploration C-11 encountered ±8 inches of base material that appeared to include

±4 inches of AC millings and gravel over ±4 inches of sandy gravel. See pavement

core log for additional details.

Appendix C

Field and Laboratory Test Results




Table 1C. Summary of DCP Test Results

Exploration Initial Test

Depth (inches)

Soil Description 1Average DCP

(mm/blow)

2Average Mr

(psi)

3Corrected Mr

(psi)

4Correlated CBR Value

C-1 4 CRUSHED GRAVEL (GW) 4.6 27,046 16,769 -

21 Sandy SILT, some clay (ML) 73.0 9,198 3,219 2.1

C-2

6 GRAVEL (GP) 33.4 12,482 7,739 -

12 Silty CLAY to SILT, some

clay, sand and gravel (CL to ML)

54.5 10,311 3,609 2.4

C-3

4 CRUSHED GRAVEL, some sand and silt (GW-GM)

4.8 26,650 16,523 -



42.3 11,377 3,982 2.7

C-4 5 CRUSHED GRAVEL,

some sand and silt (GW-GM) 3.9 28,846 17,885 -

14 CLAY (CH) 56.2 10,183 3,564 2.4

C-5 5 Sandy GRAVEL, some silt

(GW-GM) 7.5 22,344 13,853 -

11.5 Silty CLAY (CL to ML) 32.0 12,688 4,441 3.0

C-6 4 CRUSHED GRAVEL (GW) 2.5 34,103 21,144 -

12 CLAY (CH) 36.3 12,081 4,228 2.8

C-7

4 CRUSHED GRAVEL, some sand (GW)

5.3 25,615 15,881 -

12.5 Gravelly SILT, some clay (ML) 43.6 11,249 3,937 2.6

C-8

4.5 CRUSHED GRAVEL, some sand (GW) 8.7 21,110 13,088 -

12.5 Silty GRAVEL, some sand (GM) 10.1 19,911 6,969 4.6

Notes: 1. DCP (mm/blow) based on the average readings from the initial test depth. 2. Mr value based on average DCP value at the test depth and the ODOT recommended correlation:

Mr = 49,023 (DCP)-0.39. Values may vary slightly due to rounding. 3. Corrected Mr value is based on the ODOT recommended correction factors of 0.62 for base rock

and 0.35 for subgrade. 4. Correlated CBR value for subgrade is based on the FAA recommended correlation of

MR = 1,500*CBR.


Table 1C. Summary of DCP Test Results (continued)

Exploration Initial Test

Depth (inches)

Soil Description 1Average DCP

(mm/blow)

2Average Mr

(psi)

3Corrected Mr

(psi)

4Correlated CBR Value

C-9

6 Sandy GRAVEL (GP) 2.1 36,395 22,565 -

15.5 SILT, some clay, trace gravel (ML)

49.3 10,718 3,751 2.5

C-10 Exploration limited to AC core only. No DCP testing.

C-11

5 CRUSHED GRAVEL and AC Grindings (GW)

4.5 27,335 16,948 -



13.0 18,026 6,309 4.2

C-12

5 Sandy GRAVEL, trace silt (GP) 2.6 33,897 21,016 -

14 Sandy GRAVEL, some silt (GM) 2.3 35,527 12,435 8.3

Notes: 1. DCP (mm/blow) based on the average readings from the initial test depth. 2. Mr value based on average DCP value at the test depth and the ODOT recommended correlation:

Mr = 49,023 (DCP)-0.39. Values may vary slightly due to rounding. 3. Corrected Mr value is based on the ODOT recommended correction factors of 0.62 for base rock

and 0.35 for subgrade. 4. Correlated CBR value for subgrade is based on the FAA recommended correlation of

MR = 1,500*CBR.


Table 2C. Natural Water Content, Atterberg Limits and Percent Fines

Sample Number

Sample Depth (feet)

Natural Water

Content (%)

LL

PL

PI

Fines (%)

FAA/USCS Classification

S-1-1 1.0 – 2.0 25.7 36 25 11 55.8 ML

S-2-1 0.5 – 1.5 20.7 33 23 10 58.9 CL

S-3-1 0.5 – 1.5 12.9 GM

C-2-2 1.0 – 2.0 24.3

C-3-2 1.5 – 3.0 17.9 25 20 5 CL-ML

C-4-1 0.4 – 0.7 5.8 GW-GM

C-4-2 1.5 – 3.5 31.5

C-5-1 0.4 – 0.9 7.0 GW-GM

C-5-2 1.5 – 3.5 36.5 45 27 18 CL to ML

C-6-2 1.5 – 3.5 32.8 62 27 35 CH

C-7-2 2.0 – 3.0 20.4

C-9-2 1.5 – 2.5 20.4

C-11-2 2.0 – 3.0 24.2 38 25 13 CL to ML

Note: 1. Percent fines reported herein are based on the results from the sieve and hydrometer gradation tests. See Figures 1C through 5C.

2. Dual USCS classification CL to ML is indicated for samples C-5-2 and C-11-2 because the test results fell on the “A-line” dividing CL and ML soils. Dual USCS classification CL-ML is indicated for sample C-3-2 because the test result indicated a PI between 4 and 7 and LL less than 30. See Figure 1C (Appendix C).


Table 3C. Summary of Moisture-Density and CBR Test Results Current and Previous Projects

Project Sample Number

1,2Maximum Dry Density

(pcf)

1,2Optimum Moisture Content

(%)

LL

PI

Fines (%)

USCS 3CBR Value

Runway Extension &

Apron Rehabilitation

(2017)

S-1-1 107.7 16.2 36 11 55.8 ML 8.9

S-2-1 106.0 14.2 33 10 58.9 CL 4.3

Runway 16-34 Rehabilitation

(2010) S-4-1 97.9 21.4 38 7 49.3 ML 6.5

Access Road & Taxiways

(2000)

S-2-2 94.0 23.5 69 49 - CH 1.4

S-6-1 97.0 20.0 41 21 - CL 4.3

Notes: 1. Maximum dry density and optimum moisture content are based on ASTM D698 moisture-density curves.

2. Maximum dry density and optimum moisture for samples S-1-1 and S-2-1 include an oversize correction because the samples included greater than 5% gravel content. See gradation curves (Figures 2C and 3C) and moisture-density curves (Figures 7C and 9C) for additional details.

3. CBR values are for samples compacted to 95% relative compaction based on the maximum dry density of ASTM D698.

Sample No. S-1-1 S-2-1 C-3-2 C-5-2 C-6-2 C-11-2Liquid Limit, LL 36 33 25 45 62 38Plastic Limit, PL 25 23 20 27 27 25Plasticity Index, PI 11 10 5 18 35 13USCS Classification ML CL CL-ML CL to ML CH CL to MLNat. Water% 25.7 22.2 17.9 36.5 32.8 24.2

Sample No. S-4-1 SHC-1-4 SHC-6-4 S-2-2 S-6-1Liquid Limit, LL 38 37 35 69 41Plastic Limit, PL 31 22 25 20 20Plasticity Index, PI 7 15 10 49 21

USCS Classification ML CL ML CH CLNat. Water% 23.5 25.2 23.0 26.2 25.3

Albany, OregonProject No. 2161117

Current and Previous Albany Municipal Airport ProjectsAlbany Municipal Airport - Runway Extension & Apron Rehabilitation

Runway Extension & Apron Rehabilitation (2017)

Runway 16-34 Rehabilitation (2010) Access Road & Taxiways (2000)

FIGURE 1CATTERBERG LIMITS TEST RESULTS

0

10

20

30

40

50

60

0 10 20 30 40 50 60 70 80 90 100

Pla

stic

ity

Ind

ex

Liquid Limit

Runway Ext. & Apron Rehab.

Runway 16-34 Rehab.

Access Road and Taxiways

A-Line

U-Line

OH or MH

CL

ML

CL-ML

CH

OL or ML

(X=NO)PERCENTFINERSIZE

PASS?SPEC.*PERCENTSIEVE

Project No:

Project:Client:

Elev./Depth:Location:Date:Source of Sample:Sample No.:

Remarks

Classification

Coefficients

Atterberg Limits

Material Description

*

AASHTO=USCS=

Cc=Cu=D10=D15=D30=D50=D60=D85=

PI=LL=PL=

Sieve Analysis ASTM D 422

10

20

30

40

50

60

70

80

90

0

100

PE

RC

EN

T F

INE

R

100 10 1 0.1 0.01 0.001500GRAIN SIZE - mm

% COBBLES% GRAVEL

CRS. FINE% SAND

CRS. MEDIUM FINE% FINES

SILT CLAY

6 in

.

3 in

.

2 in

.

1-1/

2 in

.

1 in

.

3/4

in.

1/2

in.

3/8

in.

#4 #10

#20

#30

#40

#60

#100

#140

#200

0.0 7.3 16.4 5.3 8.5 6.7 28.8 27.0

Figure2166001-634


Foundation Engineering, Inc.; Project No. 2161117

1.0-2.0'12-23-167108S-1-1

A-4(0)ML

0.00280.01910.26911.2

gravely SILT with sand

(no specification provided)

FEI Testing & Inspection, Inc.

Corvallis, OR

100.095.692.786.779.276.371.062.557.555.8

1.5 in.1 in.

3/4 in.1/2 in.1/4 in.

#4#10#40

#100#200



Project No:

Project:Client:


Remarks

Classification

Coefficients

Atterberg Limits


*

AASHTO=USCS=

Cc=Cu=D10=D15=D30=D50=D60=D85=

PI=LL=PL=

Sieve Analysis ASTM D 422

10

20

30

40

50

60

70

80

90

0

100

PE

RC

EN

T F

INE

R

100 10 1 0.1 0.01 0.001500GRAIN SIZE - mm

% COBBLES% GRAVEL

CRS. FINE% SAND


SILT CLAY

6 in

.

3 in

.

2 in

.

1-1/

2 in

.

1 in

.

3/4

in.

1/2

in.

3/8

in.

#4 #10

#20

#30

#40

#60

#100

#140

#200

0.0 1.1 14.1 4.5 17.4 4.0 34.3 24.6

Figure2166001-634



0.5-1.512-23-167108S-2-1

A-4(0)ML

0.00400.02440.09154.90

sandy SILT with sand



Corvallis, OR

100.098.994.787.184.880.362.961.858.9

1 in.3/4 in.1/2 in.1/4 in.

#4#10#40

#100#200



Project No:

Project:Client:


Remarks

Classification

Coefficients

Atterberg Limits


*

AASHTO=USCS=

Cc=Cu=D10=D15=D30=D50=D60=D85=

PI=LL=PL=

Sieve Analysis ASTM C 136/C 117

10

20

30

40

50

60

70

80

90

0

100

PE

RC

EN

T F

INE

R

100 10 1 0.1 0.01 0.001500GRAIN SIZE - mm

% COBBLES% GRAVEL

CRS. FINE% SAND


SILT CLAY

6 in

.

3 in

.

2 in

.

1-1/

2 in

.

1 in

.

3/4

in.

1/2

in.

3/8

in.

#4 #10

#20

#30

#40

#60

#100

#140

#200

0.0 13.1 43.0 15.3 14.0 1.7 12.9

Figure2166001-634



0.5-1.5'12-23-167108S-3-1

A-1-aGM

0.4692.216.118.8017.8

silty gravel with sand



Corvallis, OR

100.094.291.686.972.351.043.928.614.613.312.9

1.5 in.1.25 in.

1 in.3/4 in.1/2 in.1/4 in.

#4#10#40

#100#200



Project No:

Project:Client:


Remarks

Classification

Coefficients

Atterberg Limits


*

AASHTO=USCS=

Cc=Cu=D10=D15=D30=D50=D60=D85=

PI=LL=PL=


10

20

30

40

50

60

70

80

90

0

100

PE

RC

EN

T F

INE

R

100 10 1 0.1 0.01 0.001500GRAIN SIZE - mm

% COBBLES% GRAVEL

CRS. FINE% SAND


SILT CLAY

6 in

.

3 in

.

2 in

.

1-1/

2 in

.

1 in

.

3/4

in.

1/2

in.

3/8

in.

#4 #10

#20

#30

#40

#60

#100

#140

#200

0.0 6.1 58.9 13.5 10.9 4.8 5.8

Figure2166001-634



5-8"12-23-167108C-4-1

A-1-aGW-GM

2.8934.520.3640.9773.6410.512.616.8

well-graded gravel with silt and sand



Corvallis, OR

100.093.960.740.635.021.510.6

7.35.8

1 in.3/4 in.1/2 in.1/4 in.

#4#10#40

#100#200



Project No:

Project:Client:


Remarks

Classification

Coefficients

Atterberg Limits


*

AASHTO=USCS=

Cc=Cu=D10=D15=D30=D50=D60=D85=

PI=LL=PL=


10

20

30

40

50

60

70

80

90

0

100

PE

RC

EN

T F

INE

R

100 10 1 0.1 0.01 0.001500GRAIN SIZE - mm

% COBBLES% GRAVEL

CRS. FINE% SAND


SILT CLAY

6 in

.

3 in

.

2 in

.

1-1/

2 in

.

1 in

.

3/4

in.

1/2

in.

3/8

in.

#4 #10

#20

#30

#40

#60

#100

#140

#200

0.0 24.7 37.2 12.5 12.9 5.7 7.0

Figure2166001-634



5-11"12-23-167108C-5-1

A-1-aGW-GM

2.8547.490.2410.6222.818.1511.523.7

well-graded gravel with silt and sand



Corvallis, OR

100.096.488.275.362.943.638.125.612.7

8.47.0

1.5 in.1.25 in.

1 in.3/4 in.1/2 in.1/4 in.

#4#10#40

#100#200

Test specification:

Date:

Project:Remarks:Client:Project No.

MATERIAL DESCRIPTION

No.200Moist.AASHTOUSCSDepth

% <% >PILLSp.G.

Nat.ClassificationElev/

MOISTURE - DENSITY RELATIONSHIP TEST

Oversize correction applied to each point

Dry

den

sity

, pcf

Water content, %

87

92

97

102

107

112

5 10 15 20 25 30 35

12-23-16

Foundation Engineering, Inc.; Project No.2166001-634


55.816.8A-4(0)ML1.0-2.0'

ASTM D 698-00a Method B Standard


Figure


FEI Testing & Inspection, Inc.Corvallis, OR

Source: 7108 Sample No.: S-1-1 Elev./Depth: 1.0-2.0'

ROCK CORRECTED TEST RESULTS UNCORRECTED

18.9 % Optimum moisture = 16.2 %

100.5 pcf Maximum dry density = 107.7 pcf

With oversize correction

Without oversize correction

BEARING RATIO TEST REPORTASTM D 1883-05

BEARING RATIO TEST REPORTFEI Testing & Inspection, Inc.

Corvallis, OR

Project No: 2166001-634

Project: Albany Municipal Airport

Source of Sample: 7108 Depth: 1.0-2.0'

Sample Number: S-1-1

Date: 12-23-16


Test Description/Remarks:

Figure

107.7 16.2ML

Material DescriptionUSCS

Max.Dens.(pcf)

OptimumMoisture

(%)LL PI

MoldedDensity

(pcf)Percent ofMax. Dens.

Moisture(%)

SoakedDensity


Moisture(%)

CBR (%)

0.10 in. 0.20 in.

LinearityCorrection

(in.)

Surcharge(lbs.)

Max.Swell(%)

1 97.0 90.1 16.5 96.1 89.3 26.4 6.0 5.1 0.000 32 0.9

2 102.8 95.5 15.3 102.4 95.1 21.7 9.4 8.3 0.000 32 0.3

3 108.3 100.6 17.3 108.2 100.5 26.2 19.0 18.2 0.000 32 0.1

Pen

etra

tio

n R

esis

tan

ce (

psi

)

0

100

200

300

400

500

Penetration Depth (in.)0 0.1 0.2 0.3 0.4 0.5

Sw

ell (

%)

0

0.2

0.4

0.6

0.8

1

Elapsed Time (hrs)0 24 48 72 96

CB

R (

%)

0

10

20

30

40

Molded Density (pcf)96 99 102 105 108 111

18 blows

34 blows

56 blows

CBR at 95% Max. Density = 8.9%for 0.10 in. Penetration

Test specification:

Date:

Project:Remarks:Client:Project No.

MATERIAL DESCRIPTION

No.200Moist.AASHTOUSCSDepth

% <% >PILLSp.G.

Nat.ClassificationElev/


Oversize correction applied to each point

Dry

den

sity

, pcf

Water content, %

88

93

98

103

108

113

9 11 13 15 17 19 21

12-23-16

Foundation Engineering, Inc.; Project No.2166001-634


58.915.2A-4(0)ML0.5-1.5

ASTM D 698-00a Method A Standard


Figure


FEI Testing & Inspection, Inc.Corvallis, OR

Source: 7108 Sample No.: S-2-1 Elev./Depth: 0.5-1.5

ROCK CORRECTED TEST RESULTS UNCORRECTED

No.4

16.3 % Optimum moisture = 14.2 %

100.0 pcf Maximum dry density = 106.0 pcf

With oversize correction

Without oversize correction

BEARING RATIO TEST REPORTASTM D 1883-05

BEARING RATIO TEST REPORTFEI Testing & Inspection, Inc.

Corvallis, OR

Project No: 2166001-634

Project: Albany Municipal Airport

Source of Sample: 7108 Depth: 0.5-1.5

Sample Number: S-2-1

Date: 12-23-16


Test Description/Remarks:

Figure

106.0 14.2ML

Material DescriptionUSCS

Max.Dens.(pcf)

OptimumMoisture

(%)LL PI

MoldedDensity


Moisture(%)

SoakedDensity


Moisture(%)

CBR (%)

0.10 in. 0.20 in.

LinearityCorrection

(in.)

Surcharge(lbs.)

Max.Swell(%)

1 97.3 91.8 12.3 96.9 91.4 26.6 3.1 2.7 0.000 32 0.4

2 103.2 97.4 11.3 102.0 96.2 23.1 5.3 4.2 0.000 32 1.2

3 107.9 101.8 11.5 106.8 100.8 21.9 7.8 6.3 0.000 32 1

Pen

etra

tio

n R

esis

tan

ce (

psi

)

0

40

80

120

160

200

Penetration Depth (in.)0 0.1 0.2 0.3 0.4 0.5

Sw

ell (

%)

0

0.4

0.8

1.2

1.6

2

Elapsed Time (hrs)0 24 48 72 96

CB

R (

%)

1

3

5

7

9

Molded Density (pcf)92 96 100 104 108 112

18 blows

34 blows

56 blows

CBR at 95% Max. Density = 4.3%for 0.10 in. Penetration

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