0002 Attachment 1 - West Haven Parking Geo Technical Report.pdf

REPORT C OVER PAGE

Geotechnical Engineering Report

VACHS West Haven Parking Garage Design

West Haven, Connecticut

February 25, 2021

Terracon Project No. J2205037

Prepared for:

Guidon Design

Indianapolis, IN

Prepared by:

Terracon Consultants, Inc.

Rocky Hill, Connecticut

Terracon Consultants, Inc. 201 Hammer Mil l Road Rocky Hil l , CT 06067

P (860) 721 1900 F (860) 721 1939 terracon.com

REPORT C OVER LETTER TO SIGN

Guidon Design

1221 N. Pennsylvania Street

Indianapolis, IN 46202

Attn: Ms. Stacey Paul, P.E. – Sr. Project Manager / Civil Team Leader

P: (317) 800 6388 ext. 104

E: spaul@guidondesign.com

Re: Geotechnical Engineering Report

VACHS West Haven Parking Garage Design

950 Campbell Avenue

West Haven, Connecticut

Terracon Project No. J2205037

Dear Ms. Paul:

We have completed the Geotechnical Engineering services for the above referenced project. This study was performed in general accordance with Terracon Proposal No. PJ2205037 dated

November 3, 2020. This report presents the findings of the subsurface exploration and provides geotechnical recommendations concerning earthwork and the design and construction of foundations and floor slabs for the proposed project.

We appreciate the opportunity to be of service to you on this project. If you have any questions concerning this report or if we may be of further service, please contact us.

Sincerely, Terracon Consultants, Inc.

Shengkai Tu, P.E. Carl W. Thunberg, P.E.

Geotechnical Department Manager Senior Geotechnical Engineer

Erich L. Christiansen, P.E.

Principal

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REPORT TOPICS

INTRODUCTION

SITE CONDITIONS

PROJECT DESCRIPTION

GEOTECHNICAL CHARACTERIZATION

GEOTECHNICAL OVERVIEW

EARTHWORK

SHALLOW FOUNDATIONS

SEISMIC CONSIDERATIONS

FLOOR SLABS

FROST CONSIDERATIONS

GENERAL COMMENTS

FIGURES

Note: This report was originally delivered in a web-based format. Orange Bold text in the report indicates a referenced section heading. The PDF version also includes hyperlinks which direct the reader to that section and clicking on the GeoReport logo will bring you back to this page. For more interactive features, please view your project online at client.terracon.com.

ATTACHMENTS

EXPLORATION AND TESTING PROCEDURES

PHOTOGRAPHY LOG

SITE LOCATION AND EXPLORATION PLANS

EXPLORATION RESULTS

SUPPORTING INFORMATION

Note: Refer to each individual Attachment for a listing of contents.

http://client.terracon.com/

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INTRODUCTION

Geotechnical Engineering Report

VACHS West Haven Parking Garage Design

950 Campbell Avenue

West Haven, Connecticut

INTRODUCTION

This report presents the results of our subsurface exploration and geotechnical engineering services performed for the proposed parking garage to be located on the campus of Veterans

Affairs Medical Center (VAMC) West Haven at 950 Campbell Avenue in West Haven, Connecticut. The VAMC is a part of Veterans Affairs Connecticut Healthcare System (VACHS).

The purpose of these services is to provide information and geotechnical engineering recommendations relative to:

■ Subsurface soil and rock conditions ■ Foundation design and construction

■ Groundwater conditions ■ Floor slab design and construction

■ Site preparation and earthwork ■ Seismic site classification

■ Excavation considerations ■ Frost considerations

■ Dewatering considerations

The geotechnical field Scope of Services for this project included the advancement of eight (8) test borings to depths ranging from approximately 21.0 to 40.4 feet below existing site grades.

Maps showing the site and boring locations are shown in the Site Location and Exploration

Plan sections, respectively. The results of laboratory testing performed on soil and rock samples obtained from the site during the field exploration are included on the boring logs and/or as separate graphs in the Exploration Results section.

SITE CONDITIONS

The following description of site conditions is derived from our site visit in association with the field exploration and our review of publicly available geologic and topographic maps.

Item Description

Parcel Information

The project is located at 950 Campbell Avenue in West Haven, Connecticut.

The lot for the proposed parking garage is approximately 1.0 acre and the approximate latitude and longitude of the lot are 41.2823° N 72.9626° W. See

Site Location

VACHS West Haven Parking Garage Design ■ West Haven, Connecticut

February 25, 2021 ■ Terracon Project No. J2205037

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Item Description

Existing

Improvements The project site is an existing at-grade parking lot designated as P4.

Current Ground

Cover Asphalt paved surface and vegetated islands

Existing Topography The site is relatively level at approximate elevation (El) 90 feet.

Geology

The proposed site is an existing parking lot. It is believed that the existing fill was placed to achieve the final grade of the parking lot. The existing fill is underlain by glacial till deposits, which is overlying bedrock.

We also collected photographs at the time of our field exploration program. Representative photos are provided in our Photography Log.

PROJECT DESCRIPTION

Our initial understanding of the project was provided in our proposal and was discussed during project planning. A period of collaboration has transpired since the project was initiated, and our final understanding of the project conditions is as follows:

Item Description

Information Provided Statement of Work, VA Project Number 689-409

Project Description The project consists of a new 300 space parking garage structure that is approximately 96,000 square feet (S.F.) on the VA West Haven campus.

Proposed Structure The proposed structure is a five-story parking garage with a minimum of two stair towers and one bank of two elevators.

Building Construction Steel frame or concrete

Finished Floor Elevation To be determined (TBD), however anticipated to be at or near current grades.

Maximum Loads (provided by Guidon)

Maximum column loads are provided below:

Column 1: 885 kips

Column 2: 860 kips

Column 3: 845 kips

Columns 4 to 12: 745 kips

Column 13: 730 kips

Column 14: 645 kips

Column 15: 565 kips

Column 16: 485 kips

Column 17: 255 kips

Grading/Slopes Final grade and slope angles are expected to remain the same or incorporate minor cuts and fills.

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Item Description

Below-Grade Structures No basement or below grade level to the parking structure is planned.

Estimated Start of Construction

Unknown

GEOTECHNICAL CHARACTERIZATION

Subsurface Profile

We have developed a general characterization of the subsurface conditions based upon our review of the subsurface exploration, laboratory data, geologic setting and our understanding of the project. This characterization, termed GeoModel, forms the basis of our geotechnical calculations and evaluation of site preparation and foundation options. Conditions encountered at each exploration point are indicated on the individual logs. The individual logs can be found in the

Exploration Results section and the GeoModel can be found in the Figures section of this report.

As part of our analyses, we identified the following model layers within the subsurface profile. For a more detailed view of the model layer depths at each boring location, refer to the GeoModel.

Model Layer Layer Name General Description

1 Surface Material Bituminous concrete

2 Fill

Poorly Graded Sand to Silty Sand, trace to with gravel, occasional cobbles and boulders, contains pieces of brick and bituminous concrete, brown to gray

3 Glacial Till

Poorly Graded Sand with Silt (SP-SM) to Silty Sand (SM), trace to with gravel, occasional to frequent cobbles and boulders, brown to red-brown, dense to very dense

4 Bedrock

Schist, gray, fine to medium-grained, moderately to slightly fractured, very close to moderate fracture spacing, slightly to moderately weathered, strong rock, fair to excellent RQD

Bedrock

Bedrock was encountered and cored in five of the eight completed borings with depths ranging from 27 to 32 feet below grade, with the exception of 19 feet below grade in test boring B-7. The bedrock is classified as a gray schist with moderate to slight fracturing and fair to excellent Rock

Quality Designation (RQD), as presented in the following table:

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Soil Boring ID Bedrock Depth Below Grade (feet) RQD / Depth Below Grade (feet)

B-1 29.0 96% / 29.0 to 34.0

B-2 Not Encountered (N.E.) --

B-3 30.7 51% / 35.4 to 40.4

B-4 N.E. --

B-5 27.0 50% / 37.0 to 32.0

B-6 N.E. --

B-7 19.0 90% / 19.0 to 24.0

B-8 32.0 84% / 32.0 to 37.0

1. Borings were terminated before encountering bedrock.

Groundwater Conditions

The boreholes were observed while drilling and at completion of drilling for the presence and level of groundwater. The water levels observed in the boreholes can be found on the boring logs in

Exploration Results and are summarized below.

Boring

Number

Approximate Depth to Groundwater (feet)

While Drilling Completion of Drilling

B-1 10.0 10.0

B-2 20.0 9.5

B-3 15.0 9.5

B-4 10.0 10.0

B-5 15.0 15.0

B-6 15.0 15.0

B-7 15.0 15.0

B-8 15.0 15.0

1. Below ground surface

Groundwater was observed in all test borings within the depth of exploration. It is believed that the groundwater is between 10 and 15 feet below grade at the time of field operation. Groundwater level fluctuations occur due to seasonal variations in the amount of rainfall, runoff and other factors not evident at the time the borings were performed. Therefore, groundwater levels during construction or at other times in the life of the structure may be higher or lower. If groundwater was encountered during any construction activities, the engineer should be contacted immediately

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GEOTECHNICAL OVERVIEW

Below the asphalt surface materials, subsurface conditions generally consist of fill overlying glacial till, which is in turn underlain by bedrock. We believe these subsurface conditions are generally suitable for the proposed structure of a five-story parking garage.

As presented in Exploration Results, fill consisting of poorly graded sand with silt and silty sand with gravel, were encountered in all test borings generally ranging from 3.0 to 7.0 feet in thickness, and up to 10.0 feet at the soil boring B-5 location. In general, the fill also contains varying amounts of cobbles, boulders, bituminous concrete, wood fragments and bricks. The glacial till deposits were encountered below the fill to the maximum depth of 32.0 feet below existing grade in boring

B-8. The glacial till deposits consist of dense to very dense poorly graded sand and silty sand with varying amounts of gravel, cobbles and boulders. The glacial till overlays the weathered to competent schist bedrock.

We believe the proposed 5-story parking garage may be supported on a shallow spread foundation system bearing on undisturbed native glacial till deposits or lean concrete as presented in the Site Preparation section of this report. The effective site drainage should be completed early in the construction sequence and maintained after construction to avoid potential issues. If possible, the grading should be performed during the warmer and drier times of the year. If grading is performed during the winter months, an increased risk for possible undercutting and replacement of unstable subgrade will persist. Additional site preparation recommendations, including fill placement, are provided in the Earthwork section.

The soils which form the bearing stratum for shallow foundations are glacial till deposits which have varying amounts of fine-grained materials such as silt and clay. The drainage during construction may have an impact on workability of subgrade. The Shallow Foundations section addresses support of the parking garage foundations bearing on native undisturbed glacial till deposits or on lean concrete bearing on undisturbed glacial till. The Floor Slabs section addresses slab-on-grade support of the lowest level of the parking garage.

The General Comments section provides an understanding of the report limitations.

EARTHWORK

Earthwork is anticipated to include removal of existing pavement and landscape, excavations, and fill placement. The following sections provide recommendations for use in the preparation of specifications for the work. Recommendations include critical quality criteria, as necessary, to

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Site Preparation

Prior to earthwork operations, vegetation, pavement, concrete slabs, and abandoned subsurface structures, if present, should be removed in their entirety from the construction area. Underground utilities that are to remain in-service should be re-located as necessary. Topsoil and existing pavement encountered within the construction area should be stripped within, as well as 5 feet beyond the limits of the proposed construction after the removal and relocation of utilities. The topsoil and asphaltic pavement are not suitable for reuse as structural fill/backfill and should be disposed in a suitable manner. Alternately, the topsoil could be reused onsite in future landscaped areas.

The existing fill materials are not suitable to support the foundation or slab, and should be removed in its entirety from within and 5 feet beyond the limits of the construction. Since the underlying glacial till is the intended bearing stratum for the foundation, as discussed later in this report, it should be left to the discretion of the contractor to decide when the fill is to be removed in the construction sequence. The contractor could either selectively remove the existing fill and construct the foundations, then remove the remaining fill within the slab area, or mass excavate the fill entirely within the footprint area, then construct the foundations before backfilling the slab areas. Regardless, the construction sequencing must allow the foundations to be established within the glacial till to take advantage of the higher bearing capacity provided by the glacial till.

After existing pavement and fill is stripped, the exposed glacial till subgrade within the slab area should be proofrolled with an adequately loaded vehicle such as a fully-loaded tandem-axle dump truck, vibratory drum compactor with a minimum static weight of 10 tons, or other similar heavy construction equipment. The Geotechnical Engineer or his qualified representative should monitor the proofrolling operations. Soft areas that pump or rut excessively should be reworked or undercut and replaced with structural fill. Areas excessively deflecting under the proofroll should be delineated and subsequently addressed by the Geotechnical Engineer. Structural fill placement may commence after the subgrade stability has been verified by the Geotechnical

Engineer as well. Excessively wet or dry material should either be removed or moisture conditioned and recompacted.

Re-Use of Existing Fill

Based on our laboratory results, it is our opinion the existing fill may be selectively reused as

General and/or Structural Fill, provided it is free of deleterious material and is close to meeting our gradation requirements presented below. Reused material must be placed at moisture contents suitable for compaction purposes and be compacted to the densities recommended below. Unsuitable materials such as wood, cobbles, boulders, and deleterious material should be culled from the material prior to reuse.

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Subgrade Preparation

Prior to placement of new fill materials, the exposed first level parking garage slab subgrade should be thoroughly compacted with a heavy self-propelled compaction equipment to locate areas that are soft or unstable. Compaction should be performed after a sufficient period of dry weather to avoid degrading an otherwise acceptable subgrade and to reduce the amount of undercutting/remedial work required. If soft/unstable areas are encountered, they should be mitigated. If the areas are isolated, mitigation by limited overexcavation and replacement with competent soils (e.g. structural fill) approved by the Geotechnical Engineer at the time of construction, may suffice. When compaction has been completed to the satisfaction of the

Geotechnical Engineer, structural fill material may be placed. Parking garage foundations should bear directly on undisturbed glacial till or on lean concrete bearing on undisturbed glacial till.

The existing fill material should be removed in its entirety from the entire garage footprint and at least 5 feet beyond the outside edges of the proposed parking garage foundations. Following excavation, the exposed native subgrade soils should be evaluated by the Geotechnical Engineer for the presence of loose native soils and if encountered these conditions should be mitigated prior to placement of structural fill below the first level of the parking garage slab. Parking garage foundations should be placed directly on undisturbed glacial till or on lean concrete.

Fill Material Types

Fill required to achieve design grade should be classified as Structural Fill and General Fill. For this project, Structural Fill is material used below the at-grade floor slab and sidewalks. General fill is material used to achieve grade outside of these areas. Earthen materials used for structural and general fill should meet the following material property requirements:

Fill Type

Connecticut State Department of Transportation (CTDOT)

Item

Application

Structural Fill

(Granular Fill)

M.02.01 (Grade A) – Granular

Fill backfill for foundation walls, fill below first level garage slabs, replacement of unstable material in slope, foundation for sidewalks

General Fill

M.02.01 (Grade B) – Reclaimed

Miscellaneous Aggregate

M.02.04 – Gravel Shoulders

(Grade A)

(Upper 3 inches – Grade C) shoulders, landscape

Aggregate Base Course M.02.03 – Granular Base base for pavements, paved ditches and channels, slope protection

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Fill Type

Connecticut State Department of Transportation (CTDOT)

Item

Application

Pervious Structural

Backfill

M.02.05

– Pervious Structural

Fill area adjacent to structures

Free-Draining Materials M.02.07

– Free-Draining

Materials drainage

1. Fill should consist of approved materials that are free of organic matter and debris. Frozen material should not be used, and fill should not be placed on a frozen subgrade. A sample of each material type should be submitted to the Geotechnical Engineer for evaluation prior to use on this site.

2. Structural Fill - CTDOT gradation:

Gradation

Sieve Size A B C

5 100

3 ½ 100 90-100

1 ½ 55-100 55-95 100

¾ 45-80

¼ 25-60 25-60 25-60

No. 10 15-45 15-45 15-45

No. 40 5-25 5-25 5-25

No. 100 0-10 0-10 0-10

No. 200 0-5 0-5 0-5

3. Pervious structure backfill shall consist of broken or crushed stone, broken or crushed gravel, or reclaimed miscellaneous aggregate containing no more than 2% by weight of asphalt cement or mixtures thereof.

4. Free-draining material shall consist of sand, gravel, rock fragments, quarry run stone, broken stone, reclaimed miscellaneous aggregate containing no more than 2% by weight of asphalt cement or mixtures thereof. This material shall not have more than 70% by weight passing the No. 40 sieve and not more than

10% by weight passing the No. 200 sieve.

Fill Compaction Requirements

Structural and general fill should meet the following compaction requirements.

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Item Structural Fill General Fill

Maximum Fill Layer Thickness

■ 12 inches or less in loose thickness when heavy, self-propelled compaction equipment is used.

■ 6 inches in loose thickness when hand-guided equipment (i.e. jumping jack or plate compactor) is used.

Minimum Compaction

Requirements

At least 95% of the maximum dry density as determined by ASTM D1557, Method C

95% of maximum dry density as determined by ASTM D698

Water Content

Range

Granular: ±2% of optimum As required to achieve minimum compaction requirements

1. Maximum density and optimum water content as determined by the standard Proctor test (ASTM D698 or

D1557). We recommend testing fill for moisture content and compaction during placement. If the results of in-place density tests indicate the specified moisture or compaction limits have not been met, the area represented by the test should be reworked and retested, as required, until the specified moisture and compaction requirements are achieved.

Grading and Drainage

All grades must provide effective drainage away from the parking garage first floor level during and after construction and should be maintained throughout the life of the structure. Water retained next to the building can result in soil movements greater than those discussed in this report. Greater movements can result in unacceptable differential lowest level garage slab, and/or foundation movements, cracked slabs and walls, and roof leaks. The roof should have gutters/drains with downspouts that discharge onto splash blocks at a distance of at least 10 feet from the building or tied into the storm drainage system.

Exposed ground should be sloped and maintained at a minimum 5% away from the building for at least 10 feet beyond the perimeter of the building. Locally, flatter grades may be necessary to transition ADA access requirements for flatwork. After building construction and landscaping have been completed, final grades should be verified to document effective drainage has been achieved. Grades around the structure should also be periodically inspected and adjusted, as necessary, as part of the structure’s maintenance program. Where paving or flatwork abuts the structure, a maintenance program should be established to effectively seal and maintain joints and prevent surface water infiltration.

Earthwork Construction Considerations

Excavations for the proposed structure are anticipated to be accomplished with conventional construction equipment. Upon completion of filling and grading, care should be taken to maintain the subgrade water content prior to construction of floor slabs. Construction traffic over the completed subgrades should be avoided. The site should also be graded to prevent ponding of surface water on the prepared subgrades or in excavations. Water collecting over or adjacent to

Responsive ■ Resourceful ■ Reliable 10 construction areas should be removed. If the subgrade freezes, desiccates, saturates, or is disturbed, the affected material should be removed, or the materials should be scarified, moisture conditioned, and recompacted prior to floor slab construction.

The groundwater table could affect overexcavation efforts, especially for over-excavation and replacement of lower strength soils. A temporary dewatering system consisting of sumps with pumps could be necessary to achieve the recommended depth of over-excavation.

As a minimum, excavations should be performed in accordance with OSHA 29 CFR, Part 1926, Subpart P, “Excavations” and its appendices, and in accordance with any applicable local, and/or state regulations.

Construction site safety is the sole responsibility of the contractor who controls the means, methods, and sequencing of construction operations. Under no circumstances shall the information provided herein be interpreted to mean Terracon is assuming responsibility for construction site safety, or the contractor's activities; such responsibility shall neither be implied nor inferred.

Construction Observation and Testing

The earthwork efforts should be monitored under the direction of the Geotechnical Engineer.

Monitoring should include documentation of adequate removal of vegetation and topsoil, proofrolling, and mitigation of areas delineated by the proofroll to require mitigation.

Each layer of compacted fill should be tested, evaluated, and reworked, as necessary, until approved by the Geotechnical Engineer prior to placement of additional lifts. Each layer of fill should be tested for density and water content at a frequency of at least one test for every 2,500 square feet of compacted fill in the building areas.

In areas of foundation excavations, the bearing subgrade should be evaluated under the direction of the Geotechnical Engineer. If unanticipated conditions are encountered, the Geotechnical

Engineer should prescribe mitigation options.

In addition to the documentation of the essential parameters necessary for construction, the continuation of the Geotechnical Engineer into the construction phase of the project provides the continuity to maintain the Geotechnical Engineer’s evaluation of subsurface conditions, including assessing variations and associated design changes.

SHALLOW FOUNDATIONS

If the site has been prepared in accordance with the requirements noted in Earthwork, the following design parameters are applicable for shallow foundations.

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Design Parameters – Compressive Loads

Item Description

Maximum Net Allowable Bearing pressure 1, 2

6,000 pounds per square foot (psf)

Required Bearing Stratum

Native undisturbed soils (dense to very dense glacial till deposits or lean concrete over glacial till)

Minimum Foundation Dimensions Columns: 30 inches

Continuous: 18 inches

Ultimate Passive Resistance

(equivalent fluid pressures)

390 pounds per cubic foot (pcf) – Structural Backfill

460 pcf – Native undisturbed soils

Ultimate Coefficient of Sliding Friction

0.55 (Native undisturbed soils)

Minimum Embedment below

Finished Grade

42 inches

Estimated Total Settlement from

Structural Loads

Less than 1 inch

Estimated Differential Settlement 2, 7

About ½ of total settlement

1. The maximum net allowable bearing pressure is the pressure in excess of the minimum surrounding overburden pressure at the footing base elevation. An appropriate factor of safety has been applied. Values assume that exterior grades are no steeper than 20% within 10 feet of structure.

2. Values provided are for maximum loads noted in Project Description.

3. Unsuitable or soft soils should be over-excavated and replaced per the recommendations presented in the Earthwork.

4. Use of passive earth pressures require the sides of the excavation for the spread footing foundation to be nearly vertical and the concrete placed neat against these vertical faces or that the footing forms be removed and compacted structural fill be placed against the vertical footing face.

5. Can be used to compute sliding resistance where foundations are placed on suitable soil/materials. Should be neglected for foundations subject to net uplift conditions.

6. Embedment necessary to minimize the effects of frost and/or seasonal water content variations. For sloping ground, maintain depth below the lowest adjacent exterior grade within 5 horizontal feet of the structure.

7. Differential settlements are as measured over a span of 50 feet.

Design Parameters - Uplift Loads

Uplift resistance of spread footings can be developed from the effective weight of the footing and the overlying soils. As illustrated on the subsequent figure, the effective weight of the soil prism defined by diagonal planes extending up from the top of the perimeter of the foundation to the ground surface at an angle, , of 20 degrees from the vertical can be included in uplift resistance.

The maximum allowable uplift capacity should be taken as a sum of the effective weight of soil plus the dead weight of the foundation, divided by an appropriate factor of safety. A maximum total unit weight of 100 pcf should be used for the backfill. This unit weight should be reduced to

40 pcf for portions of the backfill or natural soils below the groundwater elevation.

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Foundation Construction Considerations

As noted in Earthwork, the footing excavations should be evaluated under the direction of the

Geotechnical Engineer. The base of all foundation excavations should be free of water and loose soil, prior to placing concrete. Concrete should be placed soon after excavating to reduce bearing soil disturbance. Care should be taken to prevent wetting or drying of the bearing materials during construction. Excessively wet or dry material or any loose/disturbed material in the bottom of the footing excavations should be removed/reconditioned before foundation concrete is placed.

If unsuitable bearing soils are encountered at the base of the planned footing excavation, the excavation should be extended deeper to suitable soils, and the footings could bear directly on these soils at the lower level or on lean concrete backfill placed in the excavations. This is illustrated on the sketch below.

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SEISMIC CONSIDERATIONS

The seismic design requirements for buildings and other structures are based on Seismic Design

Category. Site Classification is required to determine the Seismic Design Category for a structure.

The Site Classification is based on the upper 100 feet of the site profile defined by a weighted average value of either shear wave velocity, standard penetration resistance, or undrained shear strength in accordance with Section 20.4 of ASCE 7 and the 2018 Connecticut State Building Code.

Based on the soil/bedrock properties encountered at the site and as described on the exploration logs and results, it is our professional opinion that the Seismic Site Classification is C.

Subsurface explorations at this site were extended to a maximum depth of 40.4 feet. The site properties below the boring depth to 100 feet were estimated based on our experience and knowledge of geologic conditions of the general area. Additional deeper borings or geophysical testing may be performed to confirm the conditions below the current boring depth.

FLOOR SLABS

The floor slab is expected to be supported on compacted structural fill. Design parameters for floor slabs assume the requirements in the Earthwork section have been followed. Specific attention should be given to positive drainage away from the structure and positive drainage of the aggregate base beneath the floor slab.

Floor Slab Design Parameters

Item Description

Floor Slab Support

Minimum 6 inches of Floor Slab Base Course Fill (compacted to at least 95% of ASTM D1557 2, 3

Estimated Modulus of

Subgrade Reaction

150 pounds per square inch per inch (psi/in) for point loads

1. Floor slabs should be structurally independent of building footings or walls to reduce the possibility of floor slab cracking caused by differential movements between the slab and foundation.

2. Modulus of subgrade reaction is an estimated value based upon our experience with the subgrade condition, the requirements noted in Earthwork, and the floor slab support as noted in this table. It is provided for point loads. For large area loads the modulus of subgrade reaction would be lower.

3. Free-draining granular material should have less than 5% fines (material passing the No. 200 sieve). Other design considerations such as cold temperatures and condensation development could warrant more extensive design provisions.

Saw-cut control joints should be placed in the slab to help control the location and extent of cracking. For additional recommendations refer to the ACI Design Manual. Joints or cracks should be sealed with a water-proof, non-extruding compressible compound specifically recommended for heavy duty concrete pavement and wet environments.

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Where floor slabs are tied to perimeter walls or turn-down slabs to meet structural or other construction objectives, our experience indicates differential movement between the walls and slabs will likely be observed in adjacent slab expansion joints or floor slab cracks beyond the length of the structural dowels. The Structural Engineer should account for potential differential settlement through use of sufficient control joints, appropriate reinforcing or other means.

Floor Slab Construction Considerations

Finished subgrade, within and for at least 10 feet beyond the floor slab, should be protected from traffic, rutting, or other disturbance and maintained in a relatively moist condition until floor slabs are constructed. If the subgrade should become damaged or desiccated prior to construction of floor slabs, the affected material should be removed and structural fill should be added to replace the resulting excavation. Final conditioning of the finished subgrade should be performed immediately prior to placement of the floor slab support course.

The Geotechnical Engineer should approve the condition of the floor slab subgrades immediately prior to placement of the floor slab support course, reinforcing steel, and concrete. Attention should be paid to high traffic areas that were rutted and disturbed earlier, and to areas where backfilled trenches are located.

FROST CONSIDERATIONS

The soils on this site are frost susceptible, and small amounts of water can affect the performance of the slabs on-grade. Exterior slabs should be anticipated to heave during winter months. If frost action needs to be eliminated in critical areas, we recommend the use of non-frost susceptible

(NFS) fill or structural slabs (for instance, structural stoops in front of building doors). Placement of NFS material in large areas may not be feasible; however, the following recommendations are provided to help reduce potential frost heave:

■ Provide surface drainage away from the building and slabs, and toward the site storm drainage system.

■ Install drains around the perimeter of the building, stoops, below exterior slabs and connect them to the storm drainage system.

■ Grade clayey subgrades, so groundwater potentially perched in overlying more permeable subgrades, such as sand or aggregate base, slope toward a site drainage system.

■ Place NFS fill as backfill beneath slabs critical to the project.

■ Place a 3 horizontal to 1 vertical (3H:1V) transition zone between NFS fill and other soils.

■ Place NFS materials in critical sidewalk areas.

As an alternative to extending NFS fill to the full frost depth, consideration can be made to placing extruded polystyrene or cellular concrete under a buffer of at least 2 feet of NFS material.

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GENERAL COMMENTS

Our analysis and opinions are based upon our understanding of the project, the geotechnical conditions in the area, and the data obtained from our site exploration. Natural variations will occur between exploration point locations or due to the modifying effects of construction or weather.

The nature and extent of such variations may not become evident until during or after construction.

Terracon should be retained as the Geotechnical Engineer, where noted in this report, to provide observation and testing services during pertinent construction phases. If variations appear, we can provide further evaluation and supplemental recommendations. If variations are noted in the absence of our observation and testing services on-site, we should be immediately notified so that we can provide evaluation and supplemental recommendations.

Our Scope of Services does not include either specifically or by implication any environmental or biological (e.g., mold, fungi, bacteria) assessment of the site or identification or prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the potential for such contamination or pollution, other studies should be undertaken.

Our services and any correspondence or collaboration through this system are intended for the sole benefit and exclusive use of our client for specific application to the project discussed and are accomplished in accordance with generally accepted geotechnical engineering practices with no third-party beneficiaries intended. Any third-party access to services or correspondence is solely for information purposes to support the services provided by Terracon to our client.

Reliance upon the services and any work product is limited to our client, and is not intended for third parties. Any use or reliance of the provided information by third parties is done solely at their own risk. No warranties, either express or implied, are intended or made.

Site characteristics as provided are for design purposes and not to estimate excavation cost. Any use of our report in that regard is done at the sole risk of the excavating cost estimator as there may be variations on the site that are not apparent in the data that could significantly impact excavation cost. Any parties charged with estimating excavation costs should seek their own site characterization for specific purposes to obtain the specific level of detail necessary for costing.

Site safety, and cost estimating including, excavation support, and dewatering requirements/design are the responsibility of others. If changes in the nature, design, or location of the project are planned, our conclusions and recommendations shall not be considered valid unless we review the changes and either verify or modify our conclusions in writing.

Responsive ■ Resourceful ■ Reliable

FIGURES

Contents:

GeoModel

D E

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H B

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G R

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F ee

t) VAMC 689-409 West Haven Parking Garage Design West Haven, Connecticut Terracon Project No. J2205037

Layering shown on this figure has been developed by the geotechnical engineer for purposes of modeling the subsurface conditions as required for the subsequent geotechnical engineering for this project.

Numbers adjacent to soil column indicate depth below ground surface.

NOTES:

B-1 B-2 B-3 B-4 B-5 B-6 B-7 B-8

GEOMODEL

This is not a cross section. This is intended to display the Geotechnical Model only. See individual logs for more detailed conditions.

Groundwater levels are temporal. The levels shown are representative of the date and time of our exploration. Significant changes are possible over time.

Water levels shown are as measured during and/or after drilling. In some cases, boring advancement methods mask the presence/absence of groundwater. See individual logs for details.

First Water Observation

Second Water Observation

Poorly Graded Sand with Silt (SP-SM) to Silty Sand (SM), trace to with gravel, occasional to frequent cobbles and boulders, brown to red-brown, dense to very dense

Schist, gray, fine to medium-grained, moderately to slightly fractured, very close to moderate fracture spacing, slightly to moderately weathered, strong rock, fair to excellent RQD

LEGEND

Asphalt

Fill

Silty Sand with Gravel

Schist

Lean Clay

Weathered Rock

Silty Sand

Poorly-graded Sand with Silt and Gravel

Model Layer General DescriptionLayer Name

Bituminous Concrete1

Poorly Graded Sand to Silty Sand, trace to with gravel, occasional cobbles and boulders, contains pieces of brick and bituminous concrete, brown to gray

Glacial Till

Bedrock

Surface Material

Fill

0.4

0.4

25.7

9.6

0.5

30.7

40.4

9.5

0.4

0.6

0.4

25.3

0.3

0.6

ATTACHMENTS

Responsive ■ Resourceful ■ Reliable EXPLORATION AND TESTING PROCEDURES 1 of 2

EXPLORATION AND TESTING PROCEDURES

Field Exploration

Number of Borings Boring Depth (feet) Planned Location

8 21 to 40.4 Parking Garage

Boring Layout and Elevations: Unless otherwise noted, Terracon personnel provided the boring layout. Coordinates were obtained with a handheld GPS unit (estimated horizontal accuracy of about ±10 feet) and approximate elevations were obtained by interpolation from Google Earth. If elevations and a more precise boring layout are desired, we recommend borings be surveyed following completion of fieldwork.

Subsurface Exploration Procedures: We advanced the borings with a truck-mounted rotary drill rig using continuous flight hollow stem augers. A NQ-2 core barrel was used to obtain the rock cores. Four samples were obtained in the upper 10 feet of each boring and at intervals of 5 feet thereafter. In the split-barrel sampling procedure, a standard 2-inch outer diameter split-barrel sampling spoon was driven into the ground by a 140-pound automatic hammer falling a distance of

30 inches. The number of blows required to advance the sampling spoon the last 12 inches of a normal 18-inch penetration is recorded as the Standard Penetration Test (SPT) resistance value.

The SPT resistance values, also referred to as N-values, are indicated on the boring logs at the test depths. We observed and recorded groundwater levels during and after drilling and sampling. For safety purposes, all borings were backfilled with auger cuttings after their completion. Pavements were patched with cold-mix asphalt and/or pre-mixed concrete, as appropriate.

The sampling depths, penetration distances, and other sampling information was recorded on the field boring logs. The samples were placed in appropriate containers and taken to our soil laboratory for testing and classification by a Geotechnical Engineer. Our exploration team prepared field boring logs as part of the drilling operations. These field logs included visual classifications of the materials encountered during drilling and our interpretation of the subsurface conditions between samples. Final boring logs were prepared from the field logs. The final boring logs represent the

Geotechnical Engineer's interpretation of the field logs and include modifications based on observations and tests of the samples in our laboratory.

Laboratory Testing

The project engineer reviewed the field data and assigned laboratory tests to understand the engineering properties of the various soil and rock strata, as necessary, for this project.

Procedural standards noted below are for reference to methodology in general. In some cases, variations to methods were applied because of local practice or professional judgment. Standards

Responsive ■ Resourceful ■ Reliable EXPLORATION AND TESTING PROCEDURES 2 of 2 noted below include reference to other, related standards. Such references are not necessarily applicable to describe the specific test performed.

■ ASTM D2216 Standard Test Methods for Laboratory Determination of Water (Moisture)

Content of Soil by Mass

■ ASTM D422 Standard Test Methods for Particle-Size Analysis of Soils and Hydrometer

■ ASTM C136 Standard Test Method for Particle-Size Analysis of Soils

■ ASTM D698 Standard Proctor

■ ASTM D7012 Method C for Rock Unconfined Compression

The laboratory testing program included examination of soil samples by an engineer. Based on the material’s texture and plasticity, we described and classified the soil samples in accordance with the Unified Soil Classification System.

Rock classification was conducted using locally accepted practices for engineering purposes;

petrographic analysis may reveal other rock types. Rock core samples typically provide an improved specimen for this classification. Boring log rock classification was determined using the

Description of Rock Properties.

Responsive ■ Resourceful ■ Reliable PHOTOGRAPHY LOG 1 of 2

PHOTOGRAPHY LOG

Figure 1: Truck rig setup at B-3 Figure 2: Offset at B-7 due to parked vehicle

Figure 3: Example of patched boring Figure 4: Rig setup at B-6

Responsive ■ Resourceful ■ Reliable PHOTOGRAPHY LOG 2 of 2

Figure 5: Offset for B-5 due to underground utilities

Figure 6: Underground utilities near B-5

SITE LOCATION AND EXPLORATION PLANS

Site Location

Exploration Plan

Note: All attachments are one page unless noted above.

SITE LOCATION

Note to Preparer: This is a large table with outside borders. Just click inside the table above this text box, then paste your GIS Toolbox image.

When paragraph markers are turned on you may notice a line of hidden text above and outside the table – please leave that alone. Limit editing to inside the table.

The line at the bottom about the general location is a separate table line. You can edit it as desired, but try to keep to a single line of text to avoid reformatting the page.

SITE LOC ATION

DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES MAP PROVIDED BY MICROSOFT BING MAPS

EXPLORATION PLAN

Note to Preparer: This is a large table with outside borders. Just click inside the table above this text box, then paste your GIS Toolbox image.

When paragraph markers are turned on you may notice a line of hidden text above and outside the table – please leave that alone. Limit editing to inside the table.

The line at the bottom about the general location is a separate table line. You can edit it as desired, but try to keep to a single line of text to avoid reformatting the page.

EXPLOR ATION PLAN

DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES MAP PROVIDED BY MICROSOFT BING MAPS

EXPLORATION RESULTS

Boring Logs (B-1 through B-8)

Grain Size Distribution

Moisture Density Relationship

Compressive Strength

35-41-27-19 N=68

6-7-8-7 N=15

5-3-3-7 N=6

17-22-26-28 N=48

16-34-50/4"

49-50/4"

50/4"

34-50/2"

18.2

8.7

BITUMINOUS CONCRETE

FILL - POORLY GRADED SAND (SP), with gravel, dark brown to dark gray

FILL - SILTY SAND (SM), with gravel, contains pieces of bituminous concrete, occasional cobbles and boulders, orange-brown

SILTY SAND (SM), trace gravel, occasional to frequent cobbles and boulders, red-brown, dense to very dense, (GLACIAL TILL)

0.4

7.0

86.5+/-

80+/-

Hammer Type: SafetyStratification lines are approximate. In-situ, the transition may be gradual.

Samples obtained using a 2-in. O.D. split spoon sampler

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F t.)

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R Y

In

C or e T im e

(m in

/ft

C or e R es ul ts

W A

T E

R C

O N

T E

N T

)LOCATION See Exploration Plan

Latitude: 41.2825° Longitude: -72.9629°

G R

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DEPTH ELEVATION (Ft.)

Approximate Surface Elev.: 87 (Ft.) +/-

Advancement Method:

0-29 ft: 3 1/4-inch continuous flight hollow stem augers 29-34 ft: NQ2 core barrel

Abandonment Method:

Borings backfilled with soil cuttings upon completion.

Sealed with bituminous cold patch at surface.

Notes:

Project No.: J2205037

Drill Rig: Mobile B-53

BORING LOG NO. B-1

Guidon Design, Inc.CLIENT:

Indianapolis, Indiana

Driller: T. McGovern

Boring Completed: 01-19-2021

PROJECT: VAMC 689-409 West Haven Parking Garage Design

Elevations taken from Google Earth

See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any).

See Supporting Information for explanation of symbols and abbreviations.

950 Campbell Avenue West Haven, Connecticut

SITE:

Boring Started: 01-18-2021

201 Hammer Mill Rd Rocky Hill, CT

While drilling

At completion of drilling

WATER LEVEL OBSERVATIONS

S A

M P

LE

T

Y P

E

4-4-5-6-5

REC:

in. /

100%

RQD:

57.5

in. / 96%

SILTY SAND (SM), trace gravel, occasional to frequent cobbles and boulders, red-brown, dense to very dense, (GLACIAL TILL) (continued)

SCHIST, excellent RQD, gray, fine to medium-grained, moderately fractured, very close to moderate fracture spacing, slightly weathered, strong rock

Boring Terminated at 34 Feet

29.0

34.0

58+/-

53+/-

Hammer Type: SafetyStratification lines are approximate. In-situ, the transition may be gradual.

Samples obtained using a 2-in. O.D. split spoon sampler

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-4

W

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T _R

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/2

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F t.)

F

IE

LD

T

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T R

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U

LT

S

R E

C O

V E

R Y

In

C or e T im e

(m in

/ft

C or e R es ul ts

W A

T E

R C

O N

T E

N T

)LOCATION See Exploration Plan

Latitude: 41.2825° Longitude: -72.9629°

G R

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IC

L O

G

M O

D E

L

LA

Y E

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DEPTH ELEVATION (Ft.)

Approximate Surface Elev.: 87 (Ft.) +/-

Advancement Method:

0-29 ft: 3 1/4-inch continuous flight hollow stem augers 29-34 ft: NQ2 core barrel

Abandonment Method:

Borings backfilled with soil cuttings upon completion.

Sealed with bituminous cold patch at surface.

Notes:

Project No.: J2205037

Drill Rig: Mobile B-53

BORING LOG NO. B-1

Guidon Design, Inc.CLIENT:

Indianapolis, Indiana

Driller: T. McGovern

Boring Completed: 01-19-2021

PROJECT: VAMC 689-409 West Haven Parking Garage Design

Elevations taken from Google Earth

See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any).

See Supporting Information for explanation of symbols and abbreviations.

950 Campbell Avenue West Haven, Connecticut

SITE:

Boring Started: 01-18-2021

201 Hammer Mill Rd Rocky Hill, CT

While drilling

At completion of drilling

WATER LEVEL OBSERVATIONS

S A

M P

LE

T

Y

25-18-13-27 N=31

41-38-39-43 N=77

30-41-38-43 N=79

31-37-42-48 N=79

19-31-44-50/1" N=75

27-51-50/4"

49-50/5"

47-50/2"

7.6

BITUMINOUS CONCRETE

FILL - POORLY GRADED SAND (SP), with gravel, dark brown to dark gray FILL - POORLY GRADED SAND WITH SILT (SP-SM), with gravel, contains pieces of bituminous concrete, occasional cobbles and boulders, brown to dark gray

SILTY SAND WITH GRAVEL (SM), occasional to frequent cobbles and boulders, brown, very dense, (GLACIAL TILL)

SILTY SAND (SM), trace gravel, occasional to frequent cobbles and boulders, brown, very dense, (GLACIAL TILL)

Spoon Sampler Refusal at 25.7 Feet

0.4

5.0

10.0

25.7

89.5+/-

85+/-

80+/-

64.5+/-

Hammer Type: SafetyStratification lines are approximate. In-situ, the transition may be gradual.

Samples obtained using a 2-in. O.D. split spoon sampler

T H

IS

B

O R

IN

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L O

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N O

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D F

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IN

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M A

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-4

W

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T _R

E V

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P J

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D T

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O B

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A T

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D E

P T

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F t.)

Advancement Method:

0-25 ft: 3 1/4-inch continuous flight hollow stem augers

Abandonment Method:

Borings backfilled with soil cuttings upon completion.

Sealed with bituminous cold patch at surface.

Notes:

Project No.: J2205037

Drill Rig: Mobile B-53

BORING LOG NO. B-2

Guidon Design, Inc.CLIENT:

Indianapolis, Indiana

Driller: T. McGovern

Boring Completed: 01-18-2021

PROJECT: VAMC 689-409 West Haven Parking Garage Design

Elevations taken from Google Earth

See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any).

See Supporting Information for explanation of symbols and abbreviations.

950 Campbell Avenue West Haven, Connecticut

SITE:

Boring Started: 01-18-2021

201 Hammer Mill Rd Rocky Hill, CT

While drilling

At…