ATTACHMENT 3 - GeoTech.pdf

Geotechnical Investigation Project No. 151846SA V.A. Hospital Addition January 11, 2016 – Page 1

1.0 INTRODUCTION

This report presents the results of a subsoil investigation carried out at the site of the proposed addition to the V.A. Hospital. The site is located at 650 East Indian School Road in Phoenix, Arizona.

Preliminary information calls for the construction of an addition with a full basement level. Initially only one at grade level will be constructed but additional levels may be added in the future. The basement will have a concrete cast in place wall with steel frame construction above. For the purposes of this report, it is anticipated that the finished floor elevation of the basement level will match the adjacent basement level of the existing facilities. Maximum column loads are expected to be between 400 to 1,100 kips, and no special considerations regarding settlement tolerances are known at this time. Adjacent areas will be landscaped or paved to support moderate passenger and light commercial truck traffic. Landscaped areas may be utilized for storm water retention and disposal.

2.0 GENERAL SITE AND SOIL CONDITIONS

2.1 Site Conditions

The area of the addition is bounded on the north and east by the existing hospital, on the west by the newly constructed Rehabilitation wing, and on the south by an access drive and parking followed by Indian School Road. The area is an existing landscaped area with a concrete sidewalk, concrete patio, lighting, and landscape gravel. Historically the area was previously occupied by a structure prior to 1998 with the new Rehabilitation Wing added in 2012. Refer to the following aerial photos:

Figure 2.1.1 Dated 1996 Figure 2.1.2 Dated 2010 Figure 2.1.3 Dated 2013

V.A. Hospital Addition January 11, 2016 – Page 2

2.2 Geologic Conditions

The site is located well outside known areas that have undergone considerable subsidence due to groundwater removal. Areas of subsidence are known to produce earth fissuring, which has affected areas within several miles of the site. Subsidence is a basin wide phenomenon that would result in differential elevation changes over long distances, which would not affect the type of buildings proposed for this site. No evidence of earth fissures was observed on the site. Fissure gullies form over subsurface irregularities such as bedrock highs, which cause tensional stresses and differential subsidence. Where such anomalies are not present, subsidence tends to be uniform over a wide area, this having minimal effect on surficial structures. The closest known earth fissures are located near 40th Street and Lupine, near Cactus Road and the CAP canal and in East Mesa, many miles from this site. Based on local experience, subsidence and earth fissures historically have not been a problem in this area.

2.3 Seismic Design Parameters

The project area is located in a seismic zone that is considered to have low historical seismicity. The seismicity of the Phoenix area has had only two magnitude 3.0 events in over 100 years.

Liquefaction is not considered a concern as groundwater exceeds 15 meters below ground surface.

Although borings were not advanced to 100 feet, based on the nature of the subsoils encountered in the borings and geology in the area, Site Class Definition, Class C may be used for design of the structures supported at basement level drilled shaft caissons. In addition, the following seismic parameters may be used for design, assuming a risk category IV (based on 2008 USGS maps adopted by

2012 IBC):

Table 2.3.1 Seismic Parameters

MCE1 spectral response acceleration for 0.2 second period, SS: 0.174g MCE1 spectral response acceleration for 1.0 second period, S1: 0.058g

Site coefficient, Fa: 1.2 Site coefficient, Fv: 1.7

MCE1 spectral response acceleration adjusted for site class, SMS: 0.209g MCE1 spectral response acceleration adjusted for site class, SM1: 0.098g

5% Damped spectral response acceleration, SDS: 0.139g 5% Damped spectral response acceleration, SD1: 0.065g

NOTE 1: MCE = maximum considered earthquake

V.A. Hospital Addition January 11, 2016 – Page 3

2.4 General Subsurface Conditions

The subgrade soils consist of clayey sand, sandy lean clay, and silty clay with subordinate amounts of gravel and varying degrees of calcareous cementation to the termination depths of 31.3 to 41.5 feet below existing grade. A layer of silty fine sand was indicated at a depth of 24 to 29 feet below existing grade. Standard Penetration Resistance Test (SPT) values range from 8 to 20 blows per foot in the upper ~6 feet increasing to 25 to 50+ bpf below. The upper fine grained soils are described as being in a ‘moist’ to ‘dry’ state drying out with depth at the time of investigation, based on visual and tactile evaluation.

Laboratory testing indicates the in-situ dry densities of the upper soils are on the order of

101.5 to 108.1 pcf with water contents of approximately 14.4 to 19.2 percent, at the time of the investigation.

Liquid limits range from 37 to 45 percent with plasticity indices ranging from 18 to 22. The upper clay soils exhibit volume increase due to wetting of 2.3 percent when re-compacted to moistures and densities normally expected during construction. Undisturbed samples displayed additional compression due to inundation under a maximum confining load of up to 6,400 psf.

3.0 ANALYSIS AND RECOMMENDATIONS

3.1 Analysis

It is understood that the existing structures on the north and west are supported on shallow spread footings while the tower to the east is supported on drilled shaft caissons. Based on our analysis of the field and laboratory data and the anticipated column loads of 400 to 1,100 kips it is recommended to support the proposed addition on drilled shaft caissons. For the purposes of this report, we assume that the new structure will be supported on a full basement level, located at least 10 feet below existing grades matching the existing basement level to the north and east. Basement walls may be supported on shallow spread footings bearing on undisturbed native soils or grade beams tied into the drilled shafts. If shallow spread footings are used allowance should be made for potential differential settlement between the drilled shafts and spread footings.

Groundwater is not expected to be a factor in the design or construction of foundations and underground utilities. If it appears that potential conduits of water infiltration from the surface exist, we recommend that either permeable wall backfill zones and/or strip drains be installed next to basement walls to mitigate build-up of hydrostatic pressure behind the walls. The drains should be connected to a sump drain. A sump pump should be installed to dispose of potential water that may collect from time to time.

V.A. Hospital Addition January 11, 2016 – Page 4

Given the assumed maximum anticipated construction depths at this time, we do not expect the need for de-watering of the site. Ingress of nuisance water should be controllable during construction by conventional temporary sump and pumping techniques.

For below-grade slabs (at basement level), it is anticipated that the underlying soil moisture content will remain fairly constant. Accordingly, no remedial action (such as removal and replacement) is recommended to reduce the swell potential. However if there are potential conduits for moisture from the surface or deep water lines, consideration may need to be given to provide a drainage collection system to minimize the potential for water intrusion below the slab at the basement level. This may consist of a drain tile and sump system. This will also alleviate additional hydrostatic pressure against the basement walls. It is recommended to design the slab to "float" (i.e. not attached to the foundations) to allow for some minor movement in response to minor moisture changes.

For exterior slabs-on-grade, frequent jointing is recommended to control cracking and reduce tripping hazards should differential movement occur. It is also recommended to pin the landing slab to the building floor/stem wall. This will reduce the potential for the exterior slab lifting and blocking the operation of out-swinging doors. Pinning typically consists of 24-inch long No. 4 reinforcing steel dowels placed at 12-inch centers.

3.2 Site Preparation

It is expected that excavation for the below-grade structures will result in the removal of much of the vegetation and any remnants of the current improvements from the construction area. Any other area outside the underground excavation to be occupied by the proposed construction should be stripped of all vegetation, debris, rubble, fills and obviously loose surface soils. There may also be some issues with removal of the previous shoring wall system. The original contractor is likely aware of which system was used. If a cantilever system was used, there may be some conflicts with the below grade soldier piles and the new drilled shafts and grade beams. Contact this office if there are conflicts.

3.3 Excavation And Temporary Cut Slopes

Care should be taken during excavation not to endanger nearby existing structures, roadways, utilities, etc. Due to the proximity of existing structures (including utilities), shoring will likely be required to provide structural stability and protect personnel working in the excavation.

All excavations must comply with current governmental regulations including the current

OSHA Excavation and Trench Safety Standards. Preliminary indications are that the upper fine-grained soils

V.A. Hospital Addition January 11, 2016 – Page 5 would be classified as Type C. Side slopes for open-cut excavation should be cut back at 1:1 (horizontal to vertical). The slopes should be protected from erosion due to run-off or long term surcharge at the slope crest. Construction equipment, building materials, excavated soil and vehicular traffic should not be allowed within 10 feet or one-third the slope height, whichever is greater, from the top of slope.

All cut slopes should be observed by the Soils Engineer or contractor’s qualified person during excavation. Adjustments to the recommended slopes may be necessary due to wet zones, loose strata and other conditions not observed in the borings. Localized shoring may also be required. Shotcrete or soil stabilizer on the slope face may be useful in preventing erosion due to run-off and/or drying of the slope.

Shotcrete protection is recommended for slopes that will remain open for extended periods of time (more than a week). Provision should be made for drainage (such as weep holes) to mitigate potential build-up of hydrostatic pressure below the shotcrete. If seepage from the slopes is encountered during construction, Speedie should be notified so that these recommendations can be reviewed.

3.4 Shoring

Portions of cuts may encroach on adjacent roadways and/or buildings. In areas where open-cut excavation is not feasible, consideration must be given to a shoring system. A standard system made up of steel soldier piles, lagging and tiebacks (or interior bracing), depending on depth and loading is one option. This system typically requires pre-drilling and installing heavy steel shoulder beams spaced on 8 to 10 foot centers and backfilled with lean grout. As the excavation progresses, wood lagging can be installed and tieback anchors installed and tensioned. Cantilever systems may not be possible in the deeper cut areas.

For the relatively short periods of time required to install lagging and tiebacks, excavations should stand at vertical. Sloughing soils may be encountered and require special procedures. For preliminary design of braced temporary shoring systems, we recommend the following conservative pressure diagram.

H=Depth of Excavation γ=Unit Wet Soil Weight=110 pcf (assumed)

V.A. Hospital Addition January 11, 2016 – Page 6

If shoring is required, it may be incorporated into the below-grade wall system whether the wall is cast-in-place or constructed of gunite in top down construction.

Locally, excavations have been braced using the Soil Nail technology. Several firms have experience in the immediate area. This system generally consists of excavating the cut face in increments on the order of 5 feet, installing passive tie back soil nails (anchors) and constructing a reinforced concrete (Shotcrete) face. Consideration may be given to using this system due to the local success, speed of installation and apparent economical cost. Due to the granular nature of the soil in some locations, this technology may not be efficient. Specialized contractors should make their own evaluations. Tiebacks installations are expected to encroach on other private/public property. The owner and/or contractor will have to obtain permission as required prior to tieback installation.

Prior to any excavation work commencing, consideration should be given to pre-construction surveys of surrounding buildings, roadways, utilities, etc. It is recommended that each line of shoring be monitored for movement during the construction period, or at least until the at-grade level floor is in place.

Frequent monitoring of surrounding elements should also be provided during the construction period.

3.5 Foundation Design

Drilled shaft foundations are recommended for the basement level structure. Design curves can be found in the appendix utilizing the combination of skin friction and end bearing. At this time no at-grade structures are planned. However, drilled shafts should also be used for ‘at-grade’ main structures to provide uniform bearing and mitigate potential differential settlement between ‘at-grade’ and basement level structures. Tip depths must be below the line of influence of adjacent basement level footings. (The line of influence extends outward and upward from the base of the footings at a 1:1 incline). If drilled shafts are to be located in wall backfill zones and backfill will be placed after shaft construction, then the shafts should be designed with additional length to account for potential downdrag conditions. Regardless, the influence of laterally loaded drilled shafts on basement wall loads should be considered.

As an option to supporting basement walls on grade beams and drilled shafts, shallow spread footings can be use. Shallow spread footing bearing on undisturbed native soils at the basement level can be designed with a 3,000 psf bearing capacity. This bearing capacity refers to the total of all loads, dead and live, and is a net pressure. It may be increased one-third for wind, seismic or other loads of short duration.

All footing excavations should be level and cleaned of all loose or disturbed materials.

Caissons should consist of drilled shaft foundations bearing in the medium-dense to very-dense clayey sand zone. Tie beams between caissons are not considered necessary for lateral loads up to 10 percent of the vertical load. A minimum caisson tip depth of 15 feet below the finished floor elevations are

V.A. Hospital Addition January 11, 2016 – Page 7 recommended. Actual shaft lengths may be reduced to accommodate pier caps and/or grade beams. Design and construction should assume straight shaft caissons. Sloughing could occur in the sand layer resulting in concrete quantities higher than neat dimension calculations. A minimum shaft diameter of 30 inches is recommended to allow for cleaning and inspection. All caissons should be examined by a representative of the Geotechnical Engineer to verify cleaning, depth, dimensions and proper bearing strata. Straight shaft caissons may be "machine cleaned" provided the contractor can show the ability to adequately remove loose material. Adjacent caisson base (tip) elevations should not vary by more than 45 degrees.

A minimum allowable distance of 3 caisson diameters, center-to-center, is recommended between caissons for reasons of construction safety and to reduce group action. This limitation ensures that newly placed caissons are not damaged during the subsequent placement of adjacent caissons. This distance may be reduced to 2 diameters if one of the caissons has been in place for enough time to allow concrete to set and cure. A load bearing reduction factor of 0.7 should be applied to individual caissons within a proximity of two diameters, center-to-center, of each other. If adjacent caissons are of different diameters, an average of the diameters should be used for determining spacing. All caissons should be examined by a representative of the Geotechnical Engineer to verify cleaning, depth, dimensions and proper bearing strata.

Continuous wall footings and isolated rectangular footings should be designed with minimum widths of 16 and 24 inches respectively, regardless of the resultant bearing pressure. Lightly loaded interior partitions (less than 800 plf) may be supported on reinforced thickened slab sections (minimum 12 inches of bearing width).

Estimated settlements of drilled shaft under design loads are on the order of ½ to ¾ -inch, depending on load, diameter, and length, virtually all of which will occur during construction. Post-construction differential settlements will be on the order of one-half the total settlement, under existing and compacted moisture contents. Additional localized settlements of the same magnitude could occur if native supporting soils were to experience a significant increase in moisture content. Positive drainage away from structures and controlled routing of roof runoff must be provided and maintained to prevent ponding adjacent to perimeter walls. Planters requiring heavy watering should not be placed adjacent to or within 5 feet of the building basement walls. Care should be taken in design and construction to insure that domestic and interior storm drain water is contained to prevent seepage. Roof drainage should be directed to paved areas or storm drains. They should not discharge into planters adjacent to the structures.

Continuous footings and stem walls should be reinforced to distribute stresses arising from small differential movements, and long walls should be provided with control joints to accommodate these movements. Reinforcement and control joints are suggested to allow slight movement and prevent minor floor slab cracking.

V.A. Hospital Addition January 11, 2016 – Page 8

3.6 Lateral Pressures

The following ultimate equivalent fluid lateral pressure values may be utilized for the proposed construction assuming granular wall backfill:

Active Pressures Unrestrained Walls 35 pcf At-Rest Pressures Restrained Walls 60 pcf Passive Pressures

Continuous Footings 300 pcf Spread Footings or Drilled Piers 350 pcf Coefficient of Friction (w/ passive pressure) 0.35 Coefficient of Friction (w/out passive pressure) 0.45

All backfill must be compacted to not less than 95 percent (ASTM D-698) to mobilize these passive values at low strain. Expansive soils should not be used as retaining wall backfill, except as a surface seal to limit infiltration of storm/irrigation water. The expansive pressures could greatly increase active pressures.

3.7 Fill And Backfill

Native soils are considered suitable for use in general grading and engineered structural fill below foundations but should not be used in the top 12 inches of conventional slab pad fill or as wall backfill. The top 12 inches of pad fill should be completed with an approved low or non-expansive soil, either approved imported common borrow or select granular soil. If select granular soils are used, the 4 inches of under-slab aggregate base may be included as part of the top 12 inches. Otherwise, 12 inches of approved common borrow should be used in addition to the normal 4 inches of aggregate base.

It is preferred to use well graded granular soil for wall backfill. Successful backfill of basement level walls can be difficult to achieve given generally tight access. Placement and compaction must be carefully controlled in order to minimize the potential for post construction settlement should the backfill zone be subjected to water infiltration. Even the most well controlled fine grained fills such as the native soils could experience additional settlement on the order of one to two percent of the wall height, or more, if subjected to significant moisture increases. Using well-graded granular fill will reduce that settlement potential to ½ percent. Accordingly, it is recommended to design and construct a structural slab to span over the backfill zone in the most critical areas or reinforce and pin the landing/entry

V.A. Hospital Addition January 11, 2016 – Page 9 slabs to the building stem wall to span over the backfill zone. This will reduce the potential for the exterior slab dropping and creating a tripping hazard. Critical areas can be considered to include not only concrete walkways and slabs, but also concrete and asphaltic concrete paving. Paving over wall backfill zones should be detailed to minimize the effects of backfill settlement. Utility lines, especially gravity sewer/storm drain lines, should be avoided in this backfill zone except for perpendicular building service connections. Where critical piping sensitive to settlement is required, grade beams to transfer across the fill zone should be considered. Tree wells are not recommended in basement wall backfill.

A pre-construction meeting should be held prior to starting the basement wall backfill to discuss the staging process and the procedures used for backfilling, to help minimize the potential for basement wall backfill settlement.

If imported common fill for use in site grading is required, it should be examined by a Soils Engineer to ensure that it is of low swell potential and free of organic or otherwise deleterious material. In general, the fill should have 100 percent passing the 3-inch sieve and no more than 60 percent passing the 200 sieve. For the fine fraction (passing the 40 sieve), the liquid limit and plasticity index should not exceed 30 percent and 10 percent, respectively. It should exhibit less than 1.5 percent swell potential when compacted to 95 percent of maximum dry density (ASTM D-698) at a moisture content of 2 percent below optimum, confined under a 100 psf surcharge, and inundated.

Fill should be placed on subgrade which has been properly prepared and approved by a Soils Engineer. Fill must be wetted and thoroughly mixed to achieve optimum moisture content, ±2 percent. Fill should be placed in horizontal lifts of 8-inch thickness (or as dictated by compaction equipment) and compacted to the percent of maximum dry density per ASTM D-698 set forth as follows:

A. Building Area

1. Below footing level N/A

2. Below slabs-on-grade (non-expansive soils) 95 B. Pavement Subgrade or Fill 95 C. Utility Trench Backfill 95 D. Aggregate Base Course

1. Below floor slabs 95

2. Below asphalt paving 100

E. Landscape Areas 90

V.A. Hospital Addition January 11, 2016 – Page 10

3.8 Utilities Installation

Trench excavations for shallow utilities can be accomplished by conventional trenching equipment. Trench walls may not stand near-vertical for the periods of time required to install utilities.

Trenches penetrating looser sandy deposits may experience sloughing of side walls and necessitating cutting back of side slopes and/or shoring. Adequate precautions must be taken to protect workmen in accordance with all current governmental regulations.

Backfill of trenches may be carried out with native excavated material. This material should be moisture-conditioned, placed in 8-inch lifts and mechanically compacted. Water settling is not recommended. Compaction requirements are summarized in the "Fill and Backfill" section of this report.

3.9 Slabs-On-Grade

A minimum 4-inch floor slab thickness is recommended. To facilitate fine grading operations and aid in concrete curing, a 4-inch thick layer of granular material conforming to the gradation for aggregate base (A.B.) as per M.A.G. Specification Section 702 should be utilized beneath the slab. Dried subgrade soils must be re-moistened prior to placing the aggregate base if allowed to dry out, especially if fine-grained soils are used in the top 12-inches of at grade pads.

The native soils are capable of storing a significant amount of moisture, which could increase the natural vapor drive through the slab. Accordingly, if moisture sensitive flooring and/or adhesive are planned, the use of a vapor barrier directly under the slab (at grade) is recommended. Vapor barriers should be a minimum 15-mil thick polyolefin (or equivalent), which meets ASTM E 1745 Class A specifications.

Vapor barriers do increase the potential for slab curling and water entrapment under the slab. Accordingly, if a vapor barrier is used, additional precautions such as low slump concrete, frequent jointing and proper curing will be required to reduce curling potential and detailed to prevent the entrapment of outside water sources.

3.10 Asphalt/Concrete Pavement Design

No new pavement is planned at this time, if required please contact this office for recommendations.

FIELD AND LABORATORY INVESTIGATION

On November 19, 2015, soil test borings were drilled at the approximate locations shown on the attached Soil Boring Location Plan. All exploration work was carried out under the full-time supervision of our staff engineer, who recorded subsurface conditions and obtained samples for laboratory testing. The soil borings were advanced with a truck-mounted CME-75 drill rig utilizing 7-inch diameter hollow stem flight augers. Detailed information regarding the borings and samples obtained can be found on an individual Log of Test Boring prepared for each drilling location.

Laboratory testing consisted of moisture content, dry density, grain-size distribution and plasticity

(Atterberg Limits) tests for classification and pavement design parameters. Remolded swell tests were performed on samples compacted to densities and moisture contents expected during construction.

Compression tests were performed on a selected ring sample in order to estimate settlements and determine effects of inundation. All field and laboratory data is presented in this appendix.

SW

PEAT, HUMUS, SWAMP SOILS WITH

HIGH ORGANIC CONTENTS

GRAVELS WITH

FINES

(LITTLE OR NO FINES)

CLEAN

GRAVELS

HIGHLY ORGANIC SOILS

SILTS

AND

CLAYS

SILTS

AND

CLAYS

MORE THAN 50% OF

COARSE FRACTION

PASSING ON NO. 4

SIEVE

SAND

AND

SANDY

SOILS

MORE THAN 50% OF

COARSE FRACTION

RETAINED ON NO. 4

SIEVE

GRAVEL

AND

GRAVELLY

SOILS

MORE THAN 50% OF

MATERIAL IS

SMALLER THAN NO.

200 SIEVE SIZE

FINE

GRAINED

SOILS

MAJOR DIVISIONS

LIQUID LIMIT

GREATER THAN 50

LIQUID LIMIT

LESS THAN 50

(APPRECIABLE AMOUNT

OF FINES)

SANDS WITH

FINES

MH

OL

CL

ML

SC

SM

SP

WELL-GRADED GRAVELS, GRAVEL -

SAND MIXTURES, LITTLE OR NO FINES

TYPICAL

LETTERGRAPH

SYMBOLS

ORGANIC CLAYS OF MEDIUM TO HIGH

PLASTICITY, ORGANIC SILTS

INORGANIC CLAYS OF HIGH

PLASTICITY

(LITTLE OR NO FINES)

CLEAN SANDS

(APPRECIABLE AMOUNT

OF FINES)

MORE THAN 50% OF

MATERIAL IS

LARGER THAN NO.

200 SIEVE SIZE

COARSE

GRAINED

SOILS

INORGANIC SILTS, MICACEOUS OR

DIATOMACEOUS FINE SAND OR SILTY

SOILS

ORGANIC SILTS AND ORGANIC SILTY

CLAYS OF LOW PLASTICITY

INORGANIC CLAYS OF LOW TO

MEDIUM PLASTICITY, GRAVELLY

CLAYS, SANDY CLAYS, SILTY CLAYS,

LEAN CLAYS

INORGANIC SILTS AND VERY FINE

SANDS, ROCK FLOUR, SILTY OR

CLAYEY FINE SANDS OR CLAYEY

SILTS WITH SLIGHT PLASTICITY

CLAYEY SANDS, SAND - CLAY

MIXTURES

SILTY SANDS, SAND - SILT MIXTURES

POORLY-GRADED SANDS, GRAVELLY

SAND, LITTLE OR NO FINES

WELL-GRADED SANDS, GRAVELLY

SANDS, LITTLE OR NO FINES

CLAYEY GRAVELS, GRAVEL - SAND -

CLAY MIXTURES

SILTY GRAVELS, GRAVEL - SAND -

SILT MIXTURES

POORLY-GRADED GRAVELS, GRAVEL

- SAND MIXTURES, LITTLE OR NO

FINES

PT

OH

CH

GC

GM

GP

GW

DESCRIPTIONS

NOTE: DUAL OR MODIFIED SYMBOLS MAY BE USED TO INDICATE BORDERLINE SOIL

CLASSIFICATIONS OR TO PROVIDE A BETTER GRAPHICAL PRESENTATION OF THE SOIL

Very Soft Soft Firm Stiff

Very Stiff Hard

0 - 2 2 - 4 5 - 8

9 - 15 16 - 30

> 30

0 - 0.25

0.25 - 0.5

0.5 - 1.0

1 - 2 2 - 4 > 4

Very Loose Loose

Medium Dense Dense

Very Dense

0 - 4 5 - 10

11 - 30 31 - 50

> 50

Clays & Silts Blows/Foot Strength (tons/sq ft) Sands & Gravels Blows/Foot

CONSISTENCY RELATIVE DENSITY

0.075 0.420 2.000

4.75

0.42 2.00 4.75

#200 #40 #10

#4 0.75"

#40 #10 #4

0.75" 3"

3"

12"

12"

36" mmmm Lower Limit Upper Limit

PARTICLE SIZE

MATERIAL

SIZE

SANDS

Fine

Medium Coarse

GRAVELS

Fine

Coarse

COBBLES

BOULDERS

Sieve Size Sieve Size

U.S. Standard Clear Square Openings

80 100 Liquid Limit

CL-ML

CL

20 40 60

CH

B -Line

A-Line

ML & OL

MH & OH

P lasticity Index

A grab sample taken directly from auger flights.

A grab sample taken from auger spoils or from bucket of backhoe.

Standard Penetration Test (ASTM D-1586) Driving a 2.0 inch outside diameter split spoon sampler into undisturbed soil for three successive 6-inch increments by means of a 140 lb. weight free falling through a distance of 30 inches. The cumulative number of blows for the final 12 inches of penetration is the Standard Penetration Resistance.

Driving a 3.0 inch outside diameter spoon equipped with a series of 2.42-inch inside diameter, 1-inch long brass rings, into undisturbed soil for one 12-inch increment by the same means of the Spoon Sample. The blows required for the 12 inches of penetration are recorded.

Standard Penetration Test driving a 2.0-inch outside diameter split spoon equipped with two 3-inch long, 3/8-inch inside diameter brass liners, separated by a 1-inch long spacer, into undisturbed soil by the same means of the Spoon Sample.

A 3.0-inch outside diameter thin-walled tube continuously pushed into the undisturbed soil by a rapid motion, without impact or twisting (ASTM D-1587).

Driving a 2.0-inch outside diameter "Bullnose Penetrometer" continuously into undisturbed soil by the same means of the spoon sample. The blows for each successive 12-inch increment are recorded.

DESCRIPTION

Auger SampleAS

BS Large Bulk Sample

S Spoon Sample

RS Ring Sample

LS Liner Sample

ST Shelby Tube

Continuous Penetration Resistance

DESIGNATION

SAMPLE

SOIL LEGEND

17.5

22.5

27.5

0 200 400 600 800 1000 1200 1400 1600 1800 2000

D ep th B el ow

B as em en t L ev el , f t

Allowable Axial Capacity, kips

Drilled Shaft Axial Capacity

Diameter 3' Diameter 4' Diameter 5' Diameter 6' Project No. 151846SA V.A. Hospital Addition

17.5

22.5

27.5

0 50 100 150 200 250 300 350 400 450 500

D ep th B el ow

B as em en t L ev el , f t

Allowable Uplift Capacity, kips

Drilled Shaft Uplift Capacity

Diameter 3' Diameter 4' Diameter 5' Diameter 6' Project No. 151846SA V.A. Hospital Addition