18111DVAMCPETCTGeotechReport.pdf

Geotechnical Exploration Report

Dayton VAMC PET/CT Addition

Dayton, Ohio

S&ME Project No. 1178-20-007

PREPARED FOR:

CBLH Design, Inc.

7850 Freeway Circle

Cleveland, Ohio 44130

PREPARED BY:

S&ME, Inc.

862 East Crescentville Road

Cincinnati, OH 45246

February 28, 2020

S&ME, Inc. | 862 East Crescentville Road | Cincinnati, OH 45246 | p 513.771.8471 | www.smeinc.com

CBLH Design, Inc.

7850 Freeway Circle

Cleveland, Ohio 44130

Attention: Mr. Jae Duk Cho, AIA NCARB jcho@cblhdesign.com

Reference: Geotechnical Exploration Report

Dayton VAMC PET/CT Addition

Dayton, Ohio

S&ME Project No. 1178-20-007

Dear Mr. Cho:

S&ME, Inc. (S&ME) is pleased to submit the results of our geotechnical exploration and laboratory services completed for the proposed PET/CT Addition at the Dayton VA Medical Center in Dayton, Ohio. The purpose of our project was to explore subsurface conditions at the site, evaluate those conditions, and provide recommendations for site preparation and foundations. We conducted this project in general accordance with our

Proposal No. 11-200006A, dated January 13, 2020, which was authorized by CBLH Design, Inc. (CBLH) on January

29, 2020. This report presents our understanding of the project, documents our findings, and presents our conclusions and geotechnical engineering recommendations.

S&ME appreciates the opportunity to be of service to you on this project. We look forward to helping you through project completion. If you have any questions, please call us at 513-771-8471.

Sincerely, S&ME, Inc.

Rebecca E. Scherzinger, E.I. Benjamin C. Dusina, P.E.

Staff Professional II Senior Engineer

Dayton, Ohio

S&ME Project No. 1178-20-007

February 28, 2020 ii

Table of Contents

1.0 Introduction

2.0 Site and Project Description

3.0 Site Geology

4.0 Exploration and Testing

4.1 Field Exploration

4.2 Laboratory Testing

5.0 Subsurface Conditions

6.0 Geotechnical Considerations

6.1 Geotechnical Evaluation

6.1.1 Existing Fill Material

6.1.2 Existing Utilities

6.1.3 Overexcavations

6.2 Stripping and Site Preparation

6.3 Structural Fill

6.4 Water Management

6.5 Excavation Considerations

6.6 Foundation Recommendations

6.6.1 Shallow Spread Foundations

6.6.2 General Foundation Considerations

6.7 Seismic Site Classification

6.8 Floor Slab Recommendations

6.9 Pavement Subgrade Recommendations

7.0 Follow Up Services

8.0 Final Considerations and Report Limitations

Dayton, Ohio

S&ME Project No. 1178-20-007

February 28, 2020 iii

List of Tables Table 4-1 – Summary of Unconfined Compressive Strength Testing

Table 5-1 – Summary of Subsurface Conditions

Appendices Appendix I – Additional Figures

Appendix II – Soil Boring Logs

Appendix III – Laboratory Testing

Appendix IV – ACI 302.1R-96 Form

Dayton, Ohio

S&ME Project No. 1178-20-007

February 28, 2020 1

1.0 Introduction

S&ME is pleased to submit the results of our geotechnical exploration completed for the proposed PET/CT

Addition at the Dayton VA Medical Center in Dayton, Ohio. The purpose of our project was to explore subsurface conditions at the site, evaluate those conditions, and provide recommendations for site preparation and foundations. This report presents our understanding of the project, documents our findings and presents our conclusions and geotechnical engineering recommendations.

2.0 Site and Project Description

The project site is located at the Dayton VA Medical Center in Dayton, Ohio, as shown on the vicinity map presented in Appendix I. The location of the proposed building addition is currently grass covered. A Site Plan was provided by CBLH on January 8, 2020, which indicated the proposed addition will extend east of the existing

Building 330. Concrete slab-on-grade is expected for the building floor. The site generally ranges in elevation from

973 at the southeast corner of Building 330 and sloping down to elevation 964 to the north. A photograph of the site is provided below.

D a te

: 2 /3

/2

P h o to g ra p h e r:

R e b e cc a E

. S ch e rz in g e r, E I

Location / Orientation East of Proposed Addition / Looking West

Remarks Location of proposed PET/CT Addition

Dayton, Ohio

S&ME Project No. 1178-20-007

February 28, 2020 2

3.0 Site Geology

Geologic mapping indicates the project site is within the Southern Ohio Loamy Till Plain physiographic region and the soils are loam till from the Wisconsinan age, up to 60 feet thick (Surficial geology of the Ohio portion of the

Dayton 30 x 60-minute quadrangle, Ohio Division of Geological Survey). The bedrock is the Sub-Lockport

Undifferentiated of the Silurian system (Reconnaissance Bedrock Geology of the Miamisburg, Ohio Quadrangle, Ohio Division of Geological Survey). Based on Ohio Department of Natural Resources (ODNR) well records, bedrock in this location is generally 15 to 30 feet below the existing ground surface. Most of the borings encountered bedrock (except Boring B-204) at depths ranging from 13.5 to 18.5 feet below existing grades.

4.0 Exploration and Testing

4.1 Field Exploration

On February 11, 2020 S&ME performed four (4) borings designated as B-201 through B-204 to investigate the existing soils for the proposed PET/CT Addition. The borings were located within the existing grass covered area west of Building 330. S&ME was provided with a topographic survey dated January 28, 2020.

Each of the borings were advanced to 15 to 20 feet below the surface, or auger refusal, whichever was encountered first. The borings were performed with a Diedrich D-50 track mounted drill rig using a 3-1/4 inch I.D.

hollow-stem augers to advance the borings between sampling attempts. Disturbed, but representative soil samples were attempted at 2.5 foot intervals. This sampling was done by lowering a 2-inch O.D. split-barrel sampler through the augers to the bottom of the boring and then driving the sampler into the soil with blows from a 140-pound hammer freely falling 30 inches (ASTM D1586 - Standard Penetration Test). The hammer system on the drilling rig has been calibrated in accordance with ASTM D 4633 to determine the drill rod energy ratio of 77.8%. SPT samples were examined immediately after recovery and representative portions were preserved in airtight glass jars. Upon completion of each boring, the boreholes were backfilled with soil cuttings. A

Plan of Borings showing the approximate locations of the borings is included as Figure 2 of Appendix I. Locations of the boring locations were estimated by S&ME using a hand held GPS (sub-meter horizontal accuracy) and ground surface elevations were interpolated from the provided topographic survey.

In the field, experienced personnel from S&ME supervised the drilling as well as performed the following specific duties: preserved all recovered samples; prepared a log of each boring; made seepage and groundwater observations; obtained hand-penetrometer measurements in soil samples exhibiting cohesion; and, contacted the

Project Engineer so that the program of explorations could be modified, if necessary, because of unanticipated conditions. All samples were transported to the laboratory of S&ME for further identification and testing.

4.2 Laboratory Testing

The recovered soil samples were returned to our laboratory, and visually classified by a geotechnical engineer in general accordance with the Unified Soil Classification System (ASTM D2487). Natural moisture content determinations, Atterberg limit tests, grain size analysis, and unconfined compression tests were also performed on selected sampled to aid in classification and the evaluation of the engineering properties of the soil.

Dayton, Ohio

S&ME Project No. 1178-20-007

February 28, 2020 3

Based on the results of the laboratory testing program, the soil descriptions on the boring logs were modified, if necessary, and the laboratory-corrected logs of the borings are submitted as Plates 2 through 5 in Appendix II.

The boring logs include: descriptions of the soil stratigraphy encountered; depths at which samples were procured; groundwater observations; and, values of hand-penetrometer measurements made on soil samples exhibiting cohesion.

The obtained laboratory data and descriptions of these tests are included in Appendix III. A summary of the unconfined compressive strength testing is provided in the table below.

Table 4-1 – Summary of Unconfined Compressive Strength Testing

Boring Number Sample Depth (ft) Soil Description

Unconfined

Compressive

Strength (psf)

B-201 8 to 10 Brown Lean Clay (CL) 4,270

5.0 Subsurface Conditions

Each of the borings were drilled through the grass area adjacent to the existing building. Surficial materials consisted on approximately 12 inches of topsoil/rootmat. Below the surficial material, existing fill was encountered in borings B-202, B-203, and B-204 which ranged from 6 to 13.5 feet below the existing ground surface. The fill was described as stiff to hard brown, gray, and reddish-brown Lean Clay (CL).

Natural soils encountered in the borings generally consisted of cohesive soils to depths of 13.5 to 18 feet. The cohesive soils were typically described as firm to hard brown and gray Lean Clay (CL) and Silty Clay (CL-ML). Hand penetrometer test values were typically between 0.5 and 4.5+ tons per square foot (tsf). Bedrock was encountered in each of the borings, except B-204, and consisted of shale interbedded with limestone.

For further detail of subsurface conditions encountered, refer to the individual boring logs presented on in

Appendix II. The stratum lines shown on the boring logs should be considered approximate. The following table summarizes the groundwater conditions and existing fill depths encountered in each boring.

Table 5-1 – Summary of Subsurface Conditions

Boring

Number

Depth

Groundwater

Encountered (ft)

Groundwater at Completion

(ft)

Depth of

Existing Fill (ft)

Depth to

Bedrock (ft)

B-201 11 * Dry Not Encountered 13.5

B-202 -- Dry 13.5 13.5

B-203 -- Dry 13.5 18.5

B-204 -- Dry 6 Not Encountered

* Groundwater seepage

Dayton, Ohio

S&ME Project No. 1178-20-007

February 28, 2020 4

6.0 Geotechnical Considerations

6.1 Geotechnical Evaluation

Our conclusions and recommendations are based on the design information furnished to us by CBLH and our past experience at the Medical Center. They do not reflect variations in the subsurface conditions which may exist between our borings and in unexplored areas of the site.

In general, the natural stiff to hard cohesive soils encountered at the site are considered suitable for support of the proposed structures provided that the necessary site preparation for foundation and slab support is performed as described in this report. However, it is our opinion that the construction costs for the project will be impacted by the following:

6.1.1 Existing Fill Material

Existing fill was encountered to depths ranging from 6 to 13.5 feet beneath the existing ground surface in each of the borings (except B-201) advanced during this exploration. The fill generally consisted of stiff to hard Lean Clay

(CL). No information was available regarding the history of the placement of the fill and, therefore, it is not known whether the fill was placed with compaction and control. The borings where existing fill was encountered are near existing utilities, and it is possible this existing fill was used to backfill utility trenches. The existing fill may remain below foundations if it is discontinuous (i.e., trench backfill). Based on our experience with uncontrolled fill, it is our opinion that foundations and floor slabs constructed on existing fill will be susceptible to unpredictable total and differential settlements which can lead to cracking in the concrete. Therefore, S&ME recommends one of the following options be considered for the treatment of existing fill within the building addition footprint:

Recommendations to Minimize Risk of Settlement – To minimize the potential for differential settlement of the planned foundations and floor slab, it is recommended to remove any existing fill and buried topsoil encountered within the footprint of the proposed structure and 5 feet beyond the edges of the structure footprint to expose the suitable underlying natural loose to firm silty sand soils. Based on the borings performed for this exploration, the proposed building footprint, and the estimated FFE, it is recommended that all of the existing fill will be removed to obtain the proposed grade. The overexcavation of the existing fill should be backfilled in a controlled manner up to the proposed building pad subgrade elevation. Provided new fill is placed and compacted in a controlled manner in accordance with the recommendations given in the Section 6.2 of this report, the proposed structure foundations and floor slab may then be supported on newly-placed controlled fill.

Alternative Recommendation for Foundation and Floor Slab Support – As an alternative to complete removal and replacement of the existing fill material, the Owner could consider leaving the existing fill in place for support of the foundations and floor slab if the subgrade is deemed suitable via a favorable proofroll, and the foundation bearing surface is capable of supporting a bearing capacity of 2,000 psf.

With this approach, the bottom of the interior and exterior foundations excavations must be compacted prior to reinforcing steel and concrete placement. The Owner should be made aware that there is a potential risk of differential settlement of foundations and a floor slab supported on fill that may not have been controlled. The amount of settlement cannot be quantified in existing uncontrolled fill.

Dayton, Ohio

S&ME Project No. 1178-20-007

February 28, 2020 5

Recommendations to prepare and stabilize the building subgrade to help minimize extraordinary and abrupt differential floor settlements will be provided in later sections of this report.

6.1.2 Existing Utilities

Based on the Utility Plan provided, there are several underground utilities in the vicinity of the planned construction. These utilities may need to be relocated prior to foundation excavations. It is our experience that old utilities are poorly backfilled. Expect that the backfill used around underground utility lines and structures may need to be removed and replaced with compacted soil in accordance with the recommendations presented later in this report. The excavated material may be re-used as structural fill, provided it meets the criteria for structural fill presented Section 6.3 of this report.

6.1.3 Overexcavations

As described above and in subsequent section of this report, existing fill was encountered in each of the borings performed for this exploration. Therefore, during foundation construction, overexcavations to extend shallow spread footings through existing fill or weak soil should be expected if the foundations are to be supported on natural soils. Recommendations for overexcavations are provided in Section 6.6 of this report.

6.2 Stripping and Site Preparation

To prepare the site for construction, strip and remove the topsoil/rootmat from the project area. Previously unexplored or unknown conditions could become evident during these operations to assess that adequate (but not excessive) material has been stripped. We must judge whether the recommendations in this report should be modified in view of the conditions encountered.

The existing fill should be removed and replaced from within the limits of the proposed building footprints unless the Owner is willing to accept the risk of differential settlement occurring beneath the new building foundations and floor slab (see Section 6.1 of this report).

After stripping and removal of existing fill, the exposed soil areas that are to receive structural fill or subbase stone should be evaluated by an S&ME engineer or representative by observing proof-rolling. Proof-rolling consists of applying repeated passes (4 to 5 passes) on the subgrade with a loaded dump truck, or similar rubber tired vehicle. Any materials judged to deflect excessively under the wheel loads should be undercut to more stable soils or remediated as recommended by the S&ME Engineer. If the subgrade is not accessible to a proof-roll, then the subgrade should be visually observed and probed by an experienced Geotechnical Technician to assist in identifying any soft or weak zones. It is recommended that any observed unsuitable materials, or subgrade soils which exhibit significant pumping and/or rutting during proof-rolling, either be scarified, aerated and compacted or completely removed and replaced with newly placed and compacted structural fill in accordance with recommendations presented in this report. Visual observation of the removal of these unsuitable materials by a representative of S&ME may result in at least a partial reduction of the necessary undercutting in these areas.

Once the area has been observed by S&ME, and remediated if necessary, fill material can be placed to the desired grades.

Dayton, Ohio

S&ME Project No. 1178-20-007

February 28, 2020 6

6.3 Structural Fill

S&ME recommends that suitable structural soil fill be defined as inorganic natural soil with a maximum particle size of 3 inches, a maximum dry density of at least 100 pounds per cubic foot (pcf) when tested by the standard

Proctor method (ASTM D698), and a plasticity index (PI) less than 30 percent. The existing fill soils encountered in our borings are generally suitable for re-use as structural fill provided the recommendations in this section are followed, however standard Proctor testing and Atterberg limits testing of reused fill soils is recommended to ensure unsuitable soils are not encountered during overexcavation.

Structural fill placed within three feet of the design subgrade elevation in the building area, should not consist of high plasticity clay. High plasticity clay is general characterized as having a plasticity index greater than 30. Higher plasticity clay may be used when more than three feet below the design subgrade elevation. For example, in the case of a five foot fill within the building footprint, the lower two feet of fill may consist of higher plasticity clay;

however, the upper three feet of new fill below the subgrade should consist of compacted lower plasticity clay or a dense graded aggregate (DGA).

During construction, standard Proctor testing and Atterberg limits testing of proposed fill soils should be performed by S&ME for compliance with the project specifications before they are used as fill material. If soils are imported to the site, we recommend that the soils be tested for conformance with the project specifications before being transported to the site. Please realize that the laboratory conformance testing usually takes three to four business days to complete. Therefore, the Contractor should plan accordingly.

Structural fill placement should occur in relatively thin (6 to 8-inch maximum) layers and be compacted to at least

98 percent of the standard Proctor maximum dry density beneath new floor slabs and foundations, and to at least

95 percent of the standard Proctor maximum dry density beneath the proposed pavement areas. The moisture content of the fill should be maintained within 3 percent of the soil’s optimum moisture content even though compaction may be achieved at moisture contents outside the specified range.

In-place density testing must be performed on structural fill to confirm that the recommended compaction criteria have been achieved. This allows our project engineer to monitor the quality of the fill construction and assess that the design criterion is being achieved in the field. We further recommend that these tests be performed on a full-time basis by S&ME. The testing frequency for density tests performed on a full-time basis may then be determined by our personnel based on the area to be tested, the grading equipment used, project specifications, and construction schedule. Tests should be performed at vertical intervals of 8-inches or less (the recommended lift thickness) as the fill is being placed.

6.4 Water Management

The on-site soils (both natural and existing fill) are sensitive to changes in moisture content. If grading operations are performed during periods of wet weather, these materials will not perform satisfactorily with regard to site access and stability. If the site soils become wet during construction, the owner should retain S&ME to send an

Engineer to the site to assess the area and make recommendations for remediation.

Dayton, Ohio

S&ME Project No. 1178-20-007

February 28, 2020 7

The contractor should make provisions to direct water away from the excavations during construction via site grading, drainage ditches, sump pits, etc. Water should never be allowed to pond in or around the foundation and floor slab excavations.

At the discretion of the S&ME Engineer, probing or excavation of shallow test pits may be requested, based on the observed conditions at the time of construction. To reduce, but not eliminate, access problems associated with the on-site soils, we recommend that the earthwork portion of this project be performed during the warm, dry summer months of the year.

For any below grade excavations, subsurface water may seasonally impact the excavations. We recommend the design include provisions such as foundation drains tied to nearby storm sewer systems or sump pits and sump pumps to discharge any water that may infiltrate the below grade portion of the structures. We further recommend the below grade portions of the building be waterproofed.

6.5 Excavation Considerations

All excavations and corresponding construction for the project site must be performed without endangering the construction workers. Therefore, in accordance with OHSA Trench/Excavation Regulations (OSHA 29 CFR Part

1926), any excavations exceeding a depth of four feet for which workers will be entering the excavation/trench, the excavation sides must be sloped to the required maximum inclination or flatter (based on the soil type and strength) or braced.

The existing fill and stiff to very-stiff clay soil encountered in the borings at the project site to a maximum depth of 20 feet should be considered as an OSHA Type C soil. Therefore, the maximum slope inclination for Type C soils should be 1.5 Horizontal to 1 Vertical (1.5H: 1V) unless properly supported. S&ME recommends that the actual excavation slope layback be based upon the soil conditions encountered during the excavation, as evaluated by a

"Competent Person" in accordance with OSHA regulations.

6.6 Foundation Recommendations

Existing fill was encountered to depths ranging from 6 to 13.5 feet in the borings performed for this exploration within the new building footprint. The existing fill was placed in an unknown manner; however, the existing fill was relatively consistent and comprised of stiff to hard lean clay . The planned building foundations will likely encounter existing fill at the planned bearing elevations (designed for typical frost depths).

6.6.1 Shallow Spread Foundations

To minimize settlement of shallow spread foundations to support to proposed buildings, S&ME recommends that all existing fill material be removed from within the building footprints and 5 feet beyond the footprint until suitable natural material is encountered. Based on the boring data, this will require excavation depths of approximately 6 to 13.5 feet. The overexcavation should then be backfilled with controlled, structural fill placed in accordance with Section 6.3 of this report. If the Owner is willing to accept potential risk of differential settlement of spread foundations bearing on existing fill, the existing fill may remain in place.

Dayton, Ohio

S&ME Project No. 1178-20-007

February 28, 2020 8

S&ME recommends that shallow spread foundations bearing in stiff to very-stiff cohesive soil or newly placed and compacted structural fill be proportioned based on a maximum allowable bearing pressure of 2,000 pounds per square foot (psf). Exterior foundations should be placed at least 36 inches below finished exterior grades in accordance with local codes for frost penetration while the interior column pads may bear at minimum practical depths. A minimum foundation width of 24 inches for wall foundations and 36 inches for column foundations are recommended, regardless of calculated size. Foundations designed and constructed in accordance with the foregoing recommendations and procedures will have a factor of safety of at least 3 with respect to shearing strength.

If weaker soils are present at or just below the proposed bottom of foundation elevation, the material should be overexcavated and the foundation lowered to more suitable soils, or the overexcavation below the plan foundation bearing elevation should be filled with low strength concrete or controlled density fill (CDF) having a minimum 28-day compressive strength of at least 100 psi. The determination of removal of weak foundation bearing soils should be made by an S&ME representative present during foundation excavations.

We recommend that foundation excavations be cut neat and the foundation concrete placed directly against the trench sidewalls, whenever possible. The foundation excavations should be free of loose soil and debris, as well as free of water or frozen soil at the time of concrete placement. We recommend that the ground surface adjacent to the foundation excavations be graded to prevent surface water runoff from entering the footing excavations. It should be noted that the on-site cohesive soils, when exposed to standing water, will absorb moisture and result in a decrease in strength and an increase in compressibility. Therefore, these conditions should be prevented from occurring and it is recommended that all foundation excavations be poured the same day as excavated.

6.6.2 General Foundation Considerations

Structural loading information was not available at the time of this report; however, for the proposed structures it is anticipated that foundation settlements for the proposed structures will be within tolerable ranges (less than 1-inch of total settlement and differential settlements not exceeding 1/2-inch) provided the site preparation and foundation construction are performed in accordance with the recommendations provided in this report.

All foundation excavations should be observed by an S&ME representative to assess whether suitable bearing soils are present and capable of supporting the foundation loads as designed, and to reduce the amount of overexcavation required during excavation if existing fill or weak soils are encountered.

6.7 Seismic Site Classification

Based on the subsurface stratigraphy encountered within the borings at the project site, the encountered depth to bedrock, and the estimated stratigraphy between the bottoms of the borings and 100 feet below existing grades, it is the opinion of S&ME that the project site is best characterized by the Ohio Building Code site class D.

6.8 Floor Slab Recommendations

Dependent upon final grading, it is anticipated that the proposed floor slab will generally be supported on either newly placed and compacted fill comprised of on-site soils, or existing fill left in place. On this basis, concrete

Dayton, Ohio

S&ME Project No. 1178-20-007

February 28, 2020 9 floors may be designed as slabs-on-grade utilizing a Modulus of Subgrade Reaction of 110 pounds per cubic inch

(pci). If the existing fill is left in-place, there is a potential for differential settlement and slab cracking.

We recommend that control joints be placed in the slab around columns and along footing supported walls to reduce cracking due to shrinkage during curing. We suggest a layer of compacted dense graded aggregate (DGA) directly beneath the slab to enhance support and provide a working base for construction of the floor slab. The actual DGA thickness should be based on the floor slab design, but our experience suggests a minimum depth of

4 inches. The DGA should be moist, but not wet, as the concrete is placed to reduce curling of the slab as the concrete cures. We recommend that ACI 302.1R-96 “GUIDE FOR CONCRETE FLOOR AND SLAB CONSTRUCTION” be followed for design and placement of concrete floor slabs. A copy of ACI 302.1R-96 is included in Appendix IV of this report for your use.

Between completion of grading and slab construction, floor slab subgrades are often disturbed by weather, footing and utility line installation, and other construction activities. For this reason, the subgrade should be evaluated by an S&ME engineer immediately prior to constructing the slab. It is recommended that final subgrade preparations be performed immediately prior to the placement of the granular base material to minimize damage to the subgrade from repeated construction traffic and/or exposure to weather.

Proofrolling operations should be performed on the final subgrades to expose any soft or unsuitable bearing materials which may have developed during construction as a result of heavy construction traffic. We recommend that the proofrolling operations be performed using a fully-loaded, tandem-axle dump truck. Any soft or unsuitable material exhibiting rutting, yielding, and/or pumping during the proofroll should be either undercut to a firm bearing material and be replaced with engineered fill to re-establish final subgrade. If the subgrade is not evaluated by an S&ME engineer prior to concrete placement, S&ME must be held harmless for any claims due to poor performance of the floor slab.

6.9 Pavement Subgrade Recommendations

Prior to pavement construction, any topsoil, organic material, existing pavement, existing fill, or other unsuitable material should be removed from proposed parking areas and driveways and the pavement subgrades should be prepared as described in the Section 6.2 of this report. It is anticipated that the subgrade for the paved parking and drive areas within the project area will consist of native soils or newly placed controlled fill deemed suitable for pavement support following favorable proofrolling. Based on laboratory classification tests performed on the near surface cohesive soils and published correlations, a CBR (California Bearing Ratio) value of 5 percent may be used for the design of pavements to be placed on these materials.

In addition to proper subgrade preparation, we recommend that the pavement design and construction include surface and subsurface drainage measures. Water which infiltrates the pavement and remains trapped within the pavement components during traffic loading is one of the leading causes of premature pavement failure.

Effective design measures include the use of finger drains below pavements and/or the use of perimeter swales, perimeter edge drains, curbs, or a combination of these features to collect surface water runoff from areas adjacent to the pavement. Cohesive subgrade soils should be crowned or sloped to promote drainage of infiltrating water towards subsurface drainage collection systems. Pavement design recommendations are beyond the scope of services for this report.

Dayton, Ohio

S&ME Project No. 1178-20-007

February 28, 2020 10

7.0 Follow Up Services

Our services should not end with the submission of this geotechnical report. S&ME should be kept involved throughout the design and construction process to maintain continuity and to assess whether our recommendations are properly interpreted and implemented. To achieve this, we should be retained to review project plans and specifications with the designers to see that our recommendations are fully incorporated. We also should be retained to observe and test the site preparation, foundation construction, and building construction. If we are not allowed the opportunity to continue our involvement on this project, we cannot be held responsible for the recommendations in this report.

Our familiarity with the site and with the foundation recommendations will make us a valuable part of your construction quality assurance team. In addition, a qualified engineering technician should observe and test all structural concrete and steel. Only experienced, qualified persons trained in geotechnical engineering and familiar with foundation construction should be allowed to evaluate and test foundation excavations. Normally, full-time observation of the site work and foundation installation is appropriate.

8.0 Final Considerations and Report Limitations

The analyses, conclusions and recommendations presented in this report are based on project information provided by CBLH. After the final design plans have been generated, S&ME should be retained to review the final design plans and specifications to verify that the intent of our engineering recommendations have been properly incorporated into the design documents. S&ME cannot assume responsibility or liability for the adequacy of recommendations if S&ME is not retained to review the final plans.

The contents of this report are also based on the subsurface conditions as they existed at the time of our field exploration, and further on the assumption that the exploratory borings are representative of actual subsurface conditions throughout the area investigated. It should be noted that actual subsurface conditions between and beyond the borings might differ from those encountered at the boring locations. If subsurface conditions encountered during construction vary from those discussed in this report, S&ME should be notified immediately so that we may evaluate the effects, if any, on design and construction.

We recommend that the Owner retain S&ME to continue our involvement in the project through the subsequent phases of design and construction. Our firm is not responsible for interpretation of the data contained in this report by others.

For more information on the use and limitations of this report, please read the Geoprofessional Business

Association (GBA) document that follows this page.

Geotechnical-Engineering Report

Geotechnical Services Are Performed for Specific Purposes, Persons, and Projects Geotechnical engineers structure their services to meet the specific needs of their clients. A geotechnical-engineering study conducted for a civil engineer may not fulfill the needs of a constructor — a construction contractor — or even another civil engineer. Because each geotechnical- engineering study is unique, each geotechnical-engineering report is unique, prepared solely for the client. No one except you should rely on this geotechnical-engineering report without first conferring with the geotechnical engineer who prepared it. And no one

— not even you — should apply this report for any purpose or project except the one originally contemplated.

Read the Full Report Serious problems have occurred because those relying on a geotechnical-engineering report did not read it all. Do not rely on an executive summary. Do not read selected elements only.

Geotechnical Engineers Base Each Report on a Unique Set of Project-Specific Factors Geotechnical engineers consider many unique, project-specific factors when establishing the scope of a study. Typical factors include: the client’s goals, objectives, and risk-management preferences; the general nature of the structure involved, its size, and configuration; the location of the structure on the site; and other planned or existing site improvements, such as access roads, parking lots, and underground utilities. Unless the geotechnical engineer who conducted the study specifically indicates otherwise, do not rely on a geotechnical-engineering report that was:

• not prepared for you;

• not prepared for your project;

• not prepared for the specific site explored; or

• completed before important project changes were made.

Typical changes that can erode the reliability of an existing geotechnical-engineering report include those that affect:

• the function of the proposed structure, as when it’s changed from a parking garage to an office building, or from a light-industrial plant to a refrigerated warehouse;

• the elevation, configuration, location, orientation, or weight of the proposed structure;

• the composition of the design team; or

• project ownership.

As a general rule, always inform your geotechnical engineer of project changes—even minor ones—and request an assessment of their impact. Geotechnical engineers cannot accept responsibility or liability for problems that occur because their reports do not consider developments of which they were not informed.

Subsurface Conditions Can Change A geotechnical-engineering report is based on conditions that existed at the time the geotechnical engineer performed the study. Do not rely on a geotechnical-engineering report whose adequacy may have been affected by: the passage of time;

man-made events, such as construction on or adjacent to the site; or natural events, such as floods, droughts, earthquakes, or groundwater fluctuations. Contact the geotechnical engineer before applying this report to determine if it is still reliable. A minor amount of additional testing or analysis could prevent major problems.

Most Geotechnical Findings Are Professional Opinions Site exploration identifies subsurface conditions only at those points where subsurface tests are conducted or samples are taken. Geotechnical engineers review field and laboratory data and then apply their professional judgment to render an opinion about subsurface conditions throughout the site. Actual subsurface conditions may differ — sometimes significantly — from those indicated in your report. Retaining the geotechnical engineer who developed your report to provide geotechnical-construction observation is the most effective method of managing the risks associated with unanticipated conditions.

A Report’s Recommendations Are Not Final Do not overrely on the confirmation-dependent recommendations included in your report. Confirmation-dependent recommendations are not final, because geotechnical engineers develop them principally from judgment and opinion. Geotechnical engineers can finalize their recommendations only by observing actual subsurface conditions revealed during construction. The geotechnical engineer who developed your report cannot assume responsibility or liability for the report’s confirmation-dependent recommendations if that engineer does not perform the geotechnical-construction observation required to confirm the recommendations’ applicability.

A Geotechnical-Engineering Report Is Subject to Misinterpretation Other design-team members’ misinterpretation of geotechnical-engineering reports has resulted in costly

Important Information about This

Subsurface problems are a principal cause of construction delays, cost overruns, claims, and disputes.

While you cannot eliminate all such risks, you can manage them. The following information is provided to help.

problems. Confront that risk by having your geo technical engineer confer with appropriate members of the design team after submitting the report. Also retain your geotechnical engineer to review pertinent elements of the design team’s plans and specifications. Constructors can also misinterpret a geotechnical-engineering report. Confront that risk by having your geotechnical engineer participate in prebid and preconstruction conferences, and by providing geotechnical construction observation.

Do Not Redraw the Engineer’s Logs Geotechnical engineers prepare final boring and testing logs based upon their interpretation of field logs and laboratory data. To prevent errors or omissions, the logs included in a geotechnical-engineering report should never be redrawn for inclusion in architectural or other design drawings. Only photographic or electronic reproduction is acceptable, but recognize that separating logs from the report can elevate risk.

Give Constructors a Complete Report and Guidance Some owners and design professionals mistakenly believe they can make constructors liable for unanticipated subsurface conditions by limiting what they provide for bid preparation.

To help prevent costly problems, give constructors the complete geotechnical-engineering report, but preface it with a clearly written letter of transmittal. In that letter, advise constructors that the report was not prepared for purposes of bid development and that the report’s accuracy is limited;

encourage them to confer with the geotechnical engineer who prepared the report (a modest fee may be required) and/ or to conduct additional study to obtain the specific types of information they need or prefer. A prebid conference can also be valuable. Be sure constructors have sufficient time to perform additional study. Only then might you be in a position to give constructors the best information available to you, while requiring them to at least share some of the financial responsibilities stemming from unanticipated conditions.

Read Responsibility Provisions Closely Some clients, design professionals, and constructors fail to recognize that geotechnical engineering is far less exact than other engineering disciplines. This lack of understanding has created unrealistic expectations that have led to disappointments, claims, and disputes. To help reduce the risk of such outcomes, geotechnical engineers commonly include a variety of explanatory provisions in their reports. Sometimes labeled “limitations,” many of these provisions indicate where geotechnical engineers’ responsibilities begin and end, to help others recognize their own responsibilities and risks. Read these provisions closely. Ask questions. Your geotechnical engineer should respond fully and frankly.

Environmental Concerns Are Not Covered The equipment, techniques, and personnel used to perform an environmental study differ significantly from those used to perform a geotechnical study. For that reason, a geotechnical-engineering report does not usually relate any environmental findings, conclusions, or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Unanticipated environmental problems have led to numerous project failures. If you have not yet obtained your own environmental information, ask your geotechnical consultant for risk-management guidance. Do not rely on an environmental report prepared for someone else.

Obtain Professional Assistance To Deal with Mold Diverse strategies can be applied during building design, construction, operation, and maintenance to prevent significant amounts of mold from growing on indoor surfaces.

To be effective, all such strategies should be devised for the express purpose of mold prevention, integrated into a comprehensive plan, and executed with diligent oversight by a professional mold-prevention consultant. Because just a small amount of water or moisture can lead to the development of severe mold infestations, many mold- prevention strategies focus on keeping building surfaces dry. While groundwater, water infiltration, and similar issues may have been addressed as part of the geotechnical- engineering study whose findings are conveyed in this report, the geotechnical engineer in charge of this project is not a mold prevention consultant;

none of the services performed in connection with the geotechnical engineer’s study were designed or conducted for the purpose of mold prevention. Proper implementation of the recommendations conveyed in this report will not of itself be sufficient to prevent mold from growing in or on the structure involved.

Rely, on Your GBC-Member Geotechnical Engineer for Additional Assistance Membership in the Geotechnical Business Council of the Geoprofessional Business Association exposes geotechnical engineers to a wide array of risk-confrontation techniques that can be of genuine benefit for everyone involved with a construction project. Confer with you GBC-Member geotechnical engineer for more information.

8811 Colesville Road/Suite G106, Silver Spring, MD 20910 Telephone: 301/565-2733 Facsimile: 301/589-2017 e-mail: info@geoprofessional.org www.geoprofessional.org

Copyright 2015 by Geoprofessional Business Association (GBA). Duplication, reproduction, or copying of this document, or its contents, in whole or in part, by any means whatsoever, is strictly prohibited, except with GBA’s specific written permission. Excerpting, quoting, or otherwise extracting wording from this document is permitted only with the express written permission of GBA, and only for purposes of scholarly research or book review. Only members of GBA may use this document as a complement to or as an element of a geotechnical-engineering report. Any other firm, individual, or other entity that so uses this document without being a GBA member could be commiting negligent or intentional (fraudulent) misrepresentation.

Dayton, Ohio

S&ME Project No. 1178-20-007

Appendices

Dayton, Ohio

S&ME Project No. 1178-20-007

Appendix I – Additional Figures

N

Vicinity Map

0 3,000 6,000

AutoCAD SHX Text PET/CT Addition

AutoCAD SHX Text Dayton VA Medical Center

AutoCAD SHX Text Dayton, Ohio

AutoCAD SHX Text 1178-20-007

AutoCAD SHX Text 02/06/2020

AutoCAD SHX Text 1" = 3000'

AutoCAD SHX Text

SCALE:

AutoCAD SHX Text

DATE:

AutoCAD SHX Text

PROJECT NUMBER

AutoCAD SHX Text

FIGURE NO.

AutoCAD SHX Text Drawing Path: T:\Projects\2020\GEO\1178-20-007_CBLH_Dayton VA PET-CT Add\Graphics\Vmap, BLP.dwgT:\Projects\2020\GEO\1178-20-007_CBLH_Dayton VA PET-CT Add\Graphics\Vmap, BLP.dwg

AutoCAD SHX Text

SITE

AutoCAD SHX Text

GRAPHIC SCALE

AutoCAD SHX Text

(IN FEET)

AutoCAD SHX Text

GRAPHIC SCALE

N

Plan of Borings

0 50 100

AutoCAD SHX Text PET/CT Addition

AutoCAD SHX Text Dayton VA Medical Center

AutoCAD SHX Text Dayton, Ohio

AutoCAD SHX Text 1178-20-007

AutoCAD SHX Text 02/27/2020

AutoCAD SHX Text 1" = 50'

AutoCAD SHX Text

SCALE:

AutoCAD SHX Text

DATE:

AutoCAD SHX Text

PROJECT NUMBER

AutoCAD SHX Text

FIGURE NO.

AutoCAD SHX Text Drawing Path: T:\Projects\2020\GEO\1178-20-007_CBLH_Dayton VA PET-CT Add\Graphics\Vmap, BLP.dwgT:\Projects\2020\GEO\1178-20-007_CBLH_Dayton VA PET-CT Add\Graphics\Vmap, BLP.dwg

AutoCAD SHX Text

GRAPHIC SCALE

AutoCAD SHX Text

(IN FEET)

AutoCAD SHX Text

GRAPHIC SCALE

AutoCAD SHX Text B-201

AutoCAD SHX Text Approximate Building Location

AutoCAD SHX Text Boring Location

AutoCAD SHX Text B-202

AutoCAD SHX Text B-204

AutoCAD SHX Text B-203

Dayton, Ohio

S&ME Project No. 1178-20-007

Appendix II – Soil Boring Logs

Core Diameter Inches

BQ 1-7/16

NQ 1-7/8

HQ 2-1/2

TEST BORING RECORD LEGEND

FINE AND COARSE GRAINED SOIL INFORMATION

COARSE GRAINED SOILS

(SANDS & GRAVELS)

FINE GRAINED SOILS

(SILTS & CLAYS)

PARTICLE SIZE

N Relative Density N Consistency Qu, TSF

Estimated Boulders Greater than 300 mm (12 in)

0-0.25

0.25-0.5

0.51

1-2

4+

0-4

5-10

11-30

31-50

Over 50

Very Loose Loose

Medium Dense

Dense

Very Dense

0-1 Very Soft Cobbles 75 mm to 300 mm (3 to 12 in)

2-4 Soft Gravel 4.74 mm to 75 mm (3/16 to 3 in)

5-8 Firm Coarse Sand 2 mm to 4.75 mm

9-15 Stiff Medium Sand 0.425 mm to 2 mm

16-30 Very Stiff Fine Sand 0.075 mm to 0.425 mm

Over 31 Hard Silts & Clays Less than 0.075 mm

The STANDARD PENETRATION TEST as defined by ASTM D 1586 is a method to obtain a disturbed soil sample for examination and testing and to obtain relative density and consistency information. A standard 1.4-inch I.D./2-inch O.D. split-barrel sampler is driven three 6-inch increments with a 140 lb. hammer falling 30 inches. The hammer can either be of a trip, free-fall design, or actuated by a rope and cathead. The blow counts required to drive the sampler the final two increments are added together and designate the N-value defined in the above tables.

ROCK PROPERTIES

ROCK QUALITY DESIGNATION (RQD) ROCK HARDNESS

Percent RQD Quality Very Hard: Rock can be broken by heavy hammer blows.

0-25

25-50

50-75

75-90

90-100

Very Poor

Poor

Fair

Good

Excellent

Hard: Rock cannot be broken by thumb pressure, but can be broken by moderate hammer blows.

Moderately Hard:

Small pieces can be broken off along sharp edges by considerable hard thumb pressure; can be broken with light hammer blows.

Soft: Rock is coherent but breaks very easily with thumb pressure at sharp edges and crumbles with firm hand pressure.

Very Soft: Rock disintegrates or easily compresses when touched; can be hard to very hard soil.

Recovery =

Length of Rock Core Recovered Length of Core Run

X100

63 REC

NQ

43 RQD

RQD = Sum of 4 in. and longer Rock Pieces Recovered Length of Core Run

X100

SYMBOLS

KEY TO MATERIAL TYPES SOIL PROPERTY SYMBOLS

N: Standard Penetration, BPF

M: Moisture Content, %

LL: Liquid Limit, %

PI: Plasticity Index, %

Qp: Pocket Penetrometer Value, TSF

Qu: Unconfined Compressive Strength Estimated Qu, TSF γ D:

Dry Unit Weight, PCF

F: Fines Content

SAMPLING SYMBOLS

Topsoil

Asphalt

Crushed Limestone

Fill Material

Shot-rock Fill

Low Plasticity Inorganic Silt

High Plasticity Inorganic Silt

Low Plasticity Inorganic Clay

High Plasticity Inorganic Clay

Low Plasticity Inorganic Silt or Clay

High Plasticity Inorganic Silt or Clay

Organic Silts/Clays

Well-Graded Gravel

Poorly-Graded Gravel

Silty Gravel

Clayey Gravel

Well-Graded Sand

Poorly-Graded Sand

Silty Sand

Clayey Sand

Peat

Limestone

Sandstone

Siltstone

Claystone

Weathered Rock

Dolomite

Granite

Gneiss

Schist

Amphibolite

Metagraywacke

Phylite

Undisturbed Sample

Split-Spoon

Rock Core

Auger or Bag Sample

No Sample Recovery

Water Level After Drilling

Extended Time Reading

Core Diameter Inches

BQ 1-7/16

NQ 1-7/8

HQ 2-1/2

963.0

961.0

958.0

956.0

950.5

949.9

Topsoil/rootmat - 12 inches

Very-stiff brown LEAN CLAY (CL) and limestone fragments, damp.

Stiff brown LEAN CLAY (CL) and limestone fragments, with sand, with silt, contains wood fragments, damp.

Firm to very-stiff brown becoming gray SILTY CLAY (CL-ML), with gravel, with sand, (TILL), damp to moist.

Hard brown LEAN CLAY (CL), little gravel, little sand, (TILL), damp.

Very soft to soft brown SHALE INTERBEDDED WITH LIMESTONE, highly weathered.

- Auger Refusal at 14.1 feet.

4 - 8 - 11

5 - 6 - 4

2 - 4 - 3

8 - 11 -

50/3"

HP = 0.5 -

3.5

HP = 4.5+

HP = 2.0

2/11/2020

BORING DIAMETER (IN):

REPORT NO:

RIG TYPE:

3.25" HSA

BORING NO:

DEPTH

(FT.)

BORING COMPLETED:

SHEET

DRILLING METHOD:

BORING STARTED:

1178-20-007

OF

TEST BORING RECORD

Remarks:

PROJECT LOCATION:

ELEVATION:

HAMMER:

Dayton VAMC PET/CT Addition

Auto

JOB NO:PROJECT:

G ro un dw at er

- Seepage at 11.0 feet

- Boring "dry" at completion.

964.0

2/11/2020

MATERIAL DESCRIPTION

Dayton…