02_Geotech_Report_Subsurface_Information_for_the_KC-46A_FTC_Simulator_Phase_2_Facility.pdf

Subsurface Information for the

KC-46A FTC Simulator Phase 2 Facility Altus Air Force Base

Altus, Oklahoma

THERE IS NO EXPRESS OR IMPLIED GUARANTEE AS TO THE ACCURACY OR COMPLETENESS OF THE INFORMATION AND DATA CONTAINED HEREIN, NOR OF THE INTERPRETATION THEREOF BY BURNS & McDONNELL ENGINEERING

COMPANY, OR ANY OF THEIR REPRESENTATIVES.

THE SUBSURFACE INFORMATION AND DATA CONTAINED HEREIN DO NOT FORM A PART OF ANY CONTRACT DOCUMENT ISSUED BY BURNS & McDONNELL.

IF THIS SUBSURFACE INFORMATION IS BEING ISSUED IN ELECTRONIC (PDF) FORMAT. NOTE THAT IT CONSISTS OF A 5‐ PAGE FRONT‐END DOCUMENT WITH A 76‐PAGE APPENDIX (FLYSHEET, REPORT BY STANDARD TESTING AND BACK

COVER).

United States Army Corps of Engineers Altus Air Force Base

Altus, Oklahoma Project No. 89371

May 2016

COPYRIGHT © 2016 BURNS & McDONNELL ENGINEERING COMPANY, INC.

Project No. 89371 Subsurface Information May 2016

United States Army Corps of Engineers i Burns & McDonnell

TABLE OF CONTENTS

Page No.

1.0 GENERAL

2.0 DESIGN NOTES

3.0 WATER LEVEL INFORMATION

4.0 ADDITIONAL SUBSURFACE INFORMATION

5.0 LIMITATIONS

5.1 Document Use

5.2 Variations

APPENDIX A - SUBSURFACE EXPLORATION (FINAL), ALTUS AIR FORCE

BASE KC-46A, FTU / FTC SIMULATOR FACILITY PHASE 2,

ALTUS, OKLAHOMA, PROJECT NO. 5316-3908;

PREPARED BY STANDARD TESTING AND ENGINEERING;

DATED MAY 2, 2016.

United States Army Corps of Engineers 1 Burns & McDonnell

1.0 GENERAL

This subsurface information document consists of the data and results from a subsurface investigation described in a report titled “Subsurface Exploration (Final), Altus Air Force Base KC-46A, FTU/FTC

Simulator Facility Phase 2, Altus, Oklahoma”, dated May 2, 2016. The investigation was performed by

Standard Testing and Engineering Company (Standard Testing) of Oklahoma City, Oklahoma. The report, as prepared by Standard Testing, is included in Appendix A of this document.

Drilling and laboratory testing for this investigation was performed by Standard Testing. The drilling phase was performed February 16 through February 18, 2016. It included the completion of five (5) borings drilled to depths ranging from about 11 feet to 34 feet below existing site grade. One (1) double-ring infiltrometer test was completed near boring B-23 at two feet below the existing ground surface at the time of the subsurface investigation. Field resistivity testing was performed at the boring B-21 location. Pressuremeter testing was also conducted within select borings and depths at the time of the subsurface investigation. Laboratory tests were conducted on select available samples following the completion of drilling operations. Boring logs and laboratory test results, as prepared by Standard

Testing, are included in the report in Appendix A of this document.

Samples recovered during the subsurface investigation were transported to the laboratory by Standard

Testing. Standard Testing was not compensated to store the samples after testing and reporting beyond their customary retention period prior to disposal.

2.0 DESIGN NOTES

Geotechnical design notes as prepared by Burns & McDonnell pertinent to the current project are available for inspection at Burns & McDonnell’s Kansas City office upon prior written request.

3.0 WATER LEVEL INFORMATION

Water levels were observed by Standard Testing, refer to the applicable Appendix of this document. It should be noted by the reader that fluctuations in water levels may occur over more prolonged periods of readings and can be influenced by various outside factors. It may take groundwater several days, or longer, to reach its hydrostatic levels in holes in cohesive soils.

Seasonal variations in rainfall, changes to on-site conditions, and changes to off-site conditions can affect groundwater levels. Fluctuations in groundwater levels from those noted in logs should be anticipated

United States Army Corps of Engineers 2 Burns & McDonnell during construction. Water levels observed and recorded by others reflect only those conditions that existed at the time of investigation and may vary from true phreatic groundwater levels.

4.0 ADDITIONAL SUBSURFACE INFORMATION

Burns & McDonnell has requested from United States Army Corps of Engineers additional subsurface information in the vicinity of the Site. Burns & McDonnell was not provided with any additional information.

Burns & McDonnell has previously obtained subsurface information and prepared documents, as listed below, for the previous Phase 1 portion of this project. This information is available for review at Burns

& McDonnell’s Kansas City office upon prior written request.

1. Subsurface Information for the KC-46A Fuselage Training (FuT) and Flight Training Center

(FTC) Facilities, Altus Air Force Base, Altus, Oklahoma for the US Army Corps of Engineers;

prepared by Burns & McDonnell Engineering Company, dated October 2013.

Burns & McDonnell is aware that a significant amount of construction activity has been undertaken in the near vicinity of the Site. Additional information in the form of geotechnical reports and/or construction records associated with construction activity in the vicinity of the Site may exist. Requests for such information should be directed to United States Army Corps of Engineers.

Other than that listed or described above, Burns & McDonnell is not aware of any additional subsurface information in the vicinity of the Site. Requests for additional subsurface information should be directed to United States Army Corps of Engineers.

5.0 LIMITATIONS

5.1 Document Use

The information presented in this document has been prepared for the use of Burns & McDonnell. No other warranty, express or implied, is made as to the information included in this document. In the event that conclusions and recommendations based on data contained in this document are made by others, such conclusions and recommendations are the responsibility of others.

The information gathered and presented in this document was not obtained for an environmental audit nor to evaluate the potential for hazardous materials at the Site. The equipment, techniques, and personnel

United States Army Corps of Engineers 3 Burns & McDonnell used to perform geoenvironmental exploration differ substantially from those applied in soil and foundation engineering.

The purpose of this document is not intended as preparation for a Geotechnical Baseline Report.

5.2 Variations

The subsurface information submitted in this document is based upon data obtained from test borings completed at the approximate locations indicated in the applicable Appendix of this document. This document does not reflect variations which may occur between test borings. The nature and extent of variations between the test borings may not become evident until construction is performed. If during construction, soil, rock, and/or groundwater conditions appear to be different from those described herein, Burns & McDonnell should be advised so that recommendations made may be evaluated and modified, if necessary. Water levels, as described in this document, reflect only those conditions that existed at the time that this particular subsurface investigation was performed by Standard Testing. Fluctuations or changes in water levels and groundwater conditions can be influenced by sources outside the site investigated, by seasonal rainfall, and by changes in drainage conditions in and around the Site.

Fluctuations can occur and should be anticipated between the time of investigation and the time of construction.

APPENDIX A - SUBSURFACE EXPLORATION (FINAL), ALTUS AIR FORCE

BASE KC-46A, FTU / FTC SIMULATOR FACILITY PHASE 2,

ALTUS, OKLAHOMA, PROJECT NO. 5316-3908;

PREPARED BY STANDARD TESTING AND ENGINEERING;

DATED MAY 2, 2016.

SUBSURFACE EXPLORATION (Final)

Altus Air Force Base KC-46A FTU/ FTC Simulator Facility Phase 2

PROJECT NO. 5316-3908

May 2, 2016

Burns & McDonnell Engineering Company, Inc.

9400 Wand Parkway Kansas City, MO 64114-3319

Attn: Mr. Jason Walker, P.E.

Senior Engineer Geotechnical Department

Re: Subsurface Exploration (Final)

Altus Air Force Base KC-46A FTU/ FTC Simulator Facility Phase 2

Dear Mr. Walker:

Enclosed herewith are two (2) copies of our report covering the subsurface exploration for the subject project. This geotechnical study was authorized by Geotechnical Agreement (SP-2B GEOTECH) 160118, dated February 15, 2016.

Standard Testing and Engineering Company conducted a geotechnical investigation at the site of FTU/ FTC Simulator Facility Phase 2 at Altus Air Force Base in Altus, Oklahoma. This report contains the detailed results of the geotechnical investigation, including foundation recommendations, pavement recommendations, and construction considerations.

The subsurface soils consist of approximately 11.4 to 33.8 feet of crushed stone, fills, sandy lean clay, sandy clay, clay with sand, clay, and soil shale over weathered shale rock, and exhibit fairly low to fairly high plasticity characteristics. The estimated potential vertical rises of the soil is 1.0 inch.

Foundation recommendations include (1) Shallow Footings, or (2) Drilled Pier Foundation.

We trust that the results and recommendations contained herein will permit adequate economical design and construction of the proposed structure. Unless you specify otherwise, we will keep samples obtained from these borings in our Oklahoma City laboratory for the next thirty (30) days.

We appreciate the opportunity to assist on this project. Please call on us if we can be of further service.

Respectfully submitted, STANDARD TESTING AND ENGINEERING COMPANY

Dipendra Timalsina Sharma, E.I. Ming-Cheng Peter Shau, P.E., D.GE Staff Geotechnical Engineer Manager, Geotechnical Services

Project No. 5316-3908 Account No. 0230BUR20

CORPORATE OFFICE • OKLAHOMA CITY

3400 N Lincoln Blvd • Oklahoma City, OK 73105-5493

(405) 528-0541 • (800) 725-0541 • (405) 528-0559 FAX

902 Trails West Loop

Enid, OK 73703-6336

(580) 237-3130

(800) 725-3130

(580) 237-3211 FAX

202 SE "J" Ave Lawton, OK 73501-2481

(580) 353-0872

(800) 725-0872

(580) 353-1263 FAX

SUBSURFACE EXPLORATION (Final)

Altus Air Force Base KC-46A FTU/ FTC Simulator Facility Phase 2

PROJECT NO. 5316-3908

PREPARED FOR

Burns & McDonnell Engineering Company, Inc.

9400 Ward Parkway

Kansas City, MO 64114-3319

PREPARED BY

STANDARD TESTING AND ENGINEERING COMPANY

3400 N. Lincoln Blvd.

Oklahoma City, OK 73105 Certificate of Authorization No. 77, Expiration 6/30/2017

(405) 528-0541

Prepared By:

Reviewed By:

Dipendra Timalsina Sharma, E.I.

Ming-Cheng Peter Shau, P.E., D.GE

Staff Geotechnical Engineer Manager, Geotechnical Services

I certify my e-signature for the study entitled “Subsurface Exploration”

May 2, 2016

TABLE OF CONTENTS

Page

1. INTRODUCTION …………………………………………………………………………

1.1 Authorization…………………………………………………………………………… 1

1.2 Purpose and Scope …………………………………………………………………… 1

1.3 Project Location and Description ……………………...…………………………

2. FIELD EXPLORATION ………………………………………………………………………..3

2.1 Drilling Information…………………………………………………………………….. 3

2.2 Equipment Used........…………………………………………………………………. 3

2.3 Tests Performed..……………………………………

2.4 Subsurface Conditions………………………………………………………………… 4

2.5 Groundwater……………………………………………………………………………. 5

3. LABORATORY TESTING…………………………………………………………………….. 7

3.1 Tests Performed……………………………………………………….…………...….. 7

3.2 Laboratory Summary………………………………………………………………….. 9

4. ENGINEERING EVALUATION AND RECOMMENDATIONS…..………………………. 10

4.1 Geological Information……….……………………………………………………….10

4.2 Existing Site Condition………………………………………………………………..10

Previous Construction Activity……..….……………..………………………10 Dewatering………..………………….……………………………………….. 10 Liquefaction Potential.………………….……………………………………. 11 Expansive, Dispersive or Collapsing Conditions....………………………. 11 Evaluation of Karst Potential………………….…………………………….. 11 Corrosion Potential……………….…………….……………………………. 11

4.3 Soil Conditions……………….……………………………………………………….. 11

4.4 Seismic Site Class and Seismic Hazards………………………..………………... 12

4.5 Laboratory Testing Results…….………………………………..………………….. 12

pH and Resistivity Test Results.………………………..……..…………….12 Soluble Sulfate and Chloride Content Test Results…..……..……… Modified Proctor Test Results…....................................……..……… California Bearing Ratio (CBR) Test Results…..…..........…..……… Unconfined Compressive Strength of Soil Test Results..…… Swell-Consolidation Test Results...……………...……..………………

4.6 Earthwork Recommendations….……………………………………………..…….. 15

Building Pad Construction.………………………………………… Inert Fill Requirements.………………………………………… Satisfactory Materials.............................…………………... 16 Unsatisfactory Materials.........................…………………... 17 Subgrade Preparation........................................................................ …..17 Compaction Requirements………………………………..…………... …….17 Drainage…………….………………………………………... ……………….18

4.7 Foundation Recommendations……………….………………………………

Footing Foundation System................................................……………... 19 Pier Foundation System..…….....................................…………………... 19

4.8 Floor Slabs…......……….……………………………………………………

4.9 Lateral Earth Pressure Parameters.................................………………………... 23

4.10 Excavation Requirements (OSHA Requirements)………………………………... 26

4.11 Construction Procedures……………………………………………………………. 28

Rippability of Materials Encountered………………………………………. 28

4.12 Pavement Recommendations………………………………………………………. 29

Subgrade Preparation……………………………………………………….. 29 Pavement Sections………………………………………………………….. 29 Material and Construction…………………………………………………… 30

5. BASIS FOR RECOMMENDATIONS……….…………………..………………

5.1 General Comments………………….……………………………………………….. 32

5.2 Limitations………………….…………………………………………………………. 32

APPENDIX

Appendix A - Vicinity Map Site and Boring Location Plan Appendix B - Boring Logs

Soil Profile Key to Symbols

Definition of Descriptive Terms Appendix C - AASHTO Soil Classification System

Unified Soil Classification System Appendix D - Summary of Test Results

LIST OF TABLES

Page Preliminary Column Loads-KC-46A FTC Phase 2 Facility.....……………………………………..2 Elevation of Rock Material…………………...……………………………………………………….. 5 Elevation of Groundwater...................……...……………………………………………………….. 6 pH and Resistivity Test Results………..…………………………………………………………… 13 Soluble Sulfate and Chloride Content Test Results……………..…..…………………………… 13 Modified Proctor Test Results….................................…………..…..…………………………… 13 CBR Test Results…....................................................…………..…..…………………………… 14 Unconfined Compressive Strength Test Results (qu)…………………..................................… 14 Recommended Swell Consolidation Test Parameters.................………………………………. 15 Cut and Fill Building Pad Requirements………..…………………………………………………. 15 Over Ground Inert Fill Building Pad Requirements……..…..……………………………………. 16 Drilled Pier Capacities (Borings B-20/ B-21/ B-22)............………..……………………………. 20 Drilled Pier Capacities (Boring B-24)........................……..……………………………………….21 L-Pile Input Data...........………………………………………………………………..............…… 22 OSHA Soil Classification………..…………………………………………………………………… 27 Maximum Allowable Slopes………..…………………………………………………………… Pavement Sections………..………………………………………………………………………… 30 Recommended Transverse Joint Spacings………..……………………………………………… 31

Project No. 5316-3908 1 May 2, 2016

Section 1

INTRODUCTION

1.1 Authorization

This report presents the results of a subsurface exploration performed by Standard Testing and

Engineering Company (Standard Testing) in accordance with the proposal (P-10170F2) prepared for Mr. Jason Walker, P.E. of Burns & McDonnell Engineering Company, Inc., dated January 28, 2016, and identified as Standard Testing project number 5316-3908. We received authorization for this study through a Geotechnical Agreement (SP-2B GEOTECH) 160118 signed by Ms. Amy R.

Clement, Associate Project Manager, of Burns & McDonnell Engineering Company, Inc., dated

February 15, 2016.

1.2 Purpose and Scope

A geotechnical investigation was performed for the purpose of (1) determining the subsurface soil and groundwater conditions, (2) evaluating the bearing capacity and plasticity characteristics of the soils, and (3) making recommendations concerning the earthwork, foundation systems, and pavement section for the facility.

Five (5) exploratory borings (B-20 thru. B-24) were drilled to the depths ranging from 11.4 to 33.8 feet. The boring depths and types of testing were performed according to the scope of work proposed by Burns McDonnell and accepted by Ms. Clement. Narrative descriptions of our findings and recommendations are contained in the body of this report. Vicinity Map, site and boring location plan with boring locations, the boring logs, soil profile, and summary of test results are included in the Appendices of this report.

1.3 Project Location and Description

It is understood that this project is the second of three phase construction of the 74,120 SF Flight

Training Center Facility (FTC) at Altus Air Force Base in Altus, Oklahoma. The phase 2 facility consist of approximately 22,200 SF building addition to support the KC-46A Tanker Program. This facility will be designed to provide high bay area for Weapon System Training (WST) and Boom

Operator Training (BOT) simulators, computer room, simulator maintenance/ storage, instructor office area, secure software, secure training, mission planning, brief rooms, classrooms, learning centers, break rooms & toilet rooms, supporting mechanical, electrical and communication rooms, and modification of the phase 1 part task training rooms.

Supporting facilities include: electrical, water, sewer and gas service, communications and site improvements. Project also includes paved parking, paved drives, sidewalks, storm drainage and

Project No. 5316-3908 2 May 2, 2016 curb and gutters.

Preliminary column footing loads are as follows:

Preliminary Column Loads-KC-46A FTC Phase 2 Facility

Building Compression

(kips)

Tension

(kips)

Shear

(kips)

Flight Training Center (FTC) 200 80 60

If the project is not as described or has changed, Standard Testing must be notified in order to reevaluate the recommendations for the project.

Project No. 5316-3908 3 May 2, 2016

Section 2

FIELD EXPLORATION

2.1 Drilling Information

The field exploration work was performed and completed on 16th, 17th, and 18th February, 2016.

Conditions at the site were investigated with five (5) borings at the locations indicated on the site and boring location plan, included in Appendix "A." Boring surface elevations are reported on the individual boring logs, included in Appendix "B." The boring surface elevations were provided by the client. Boring depths were ranging from 11.4 to 33.8 feet within the facility footpring. For accurate sampling, cuttings were observed continuously during drilling with specific samples being taken at distinct lithologic changes. The equipment used, field tests performed, and soil samples taken are discussed below.

2.2 Equipment Used

Five (5) borings were drilled with a truck-mounted CME-55 rotary drilling unit equipped with 3.25"

I.D. X 7.25" O.D. hollow stem augers (HAS), 4” Solid Flight Auger (SFA), and 3” Solid Flight Auger

(SFA). Standard penetration tests (SPT) used a 1.375" ID split spoon sampler driven by an automatic hammer utilizing a 140 lb. weight falling 30 inches

2.3 Tests Performed

• Thirty-two (32) standard penetration tests were performed in order to estimate the shear strengths of the soils in their natural state. The test was conducted as specified by ASTM

D1586, "Penetration Test and Split-Barrel Sampling of Soils." The in-situ bearing strength is related to the N-value from this test. "N" is the number of blows required to drive a split-spoon sampler twelve inches, after a 6 inch seating, into undisturbed soil. The soil samples recovered in the split-spoon barrel were removed from the sample tool in the field, visually classified, and labeled according to boring number and depth. Results of the standard penetration tests are denoted at their respective depths on the boring logs.

According to Skempton, A.W. (Geotechnique, Vol. 36, No.3, pp 425-447, 1986), and hammer efficiency as follows:

N60 = CbCr[Em/60]N

Where N60=Standard Penetration Test N Value Corrected for Field Testing Procedures

Cb=Borehole Diameter Correction (Cb=1.0 for Boreholes of 3.25” in Diameter)

Cr=Rod Length Correction (Cr=0.75 for up to 13 feet of drilling rods, 0.85 for 13

Project No. 5316-3908 4 May 2, 2016 to 20 feet of drilling rods, 0.95 for 20 to 33 of drilling rods, and 1.00 for drilling rods in excess of 33 feet)

N=Measured Standard Penetration Test N Value

Em=Hammer Efficiency in Percent (Em=88% for STEC CME-55)

• Eight (8) thin-walled tube samples were taken as specified by ASTM D1587, “Standard

Practice for Thin-Walled Tube Sampling of Soils for Geotechnical Purposes.”

• A Rock Test pre-bored pressuremeter (PMT) was used to determine in-situ strength of rock materials at two (2) borings (B-20 and B-24) as specified by ASTM D4719. A total of five (5) tests were performed. This test consist of an expansion of a cylindrical cavity formed in the ground in order to measure the relationship between pressure and deformation of the rock.

The test results are presented in Appendix “D.” Please note this PMT data was not used to establish the L-PLE parameters.

• Two (2) field resistivity test were performed at north-south (N-S) and east-west (E-W) directions with electrode spacing 2.5, 5, 10, 20, and 50 feet, in accordance with ASTM G57

(field) to determine the electrical resistivity of the in-situ soils. Field resistivity test were conducted making B-21 as the center of the test. The test results are presented in Appendix

“D.”

• One (1) infiltration rate of soil test was performed in the field using double-ring infiltrometer,

2.0 feet below ground surface by excavating with a backhoe, in accordance with ASTM

D3385. The test result is presented in Appendix “D.”

Depths of individual split spoon (standard penetration tests), thin-walled tube, and grab samples are indicated on the boring logs included in Appendix "B." Split spoon and grab (bag) samples were labeled and sealed in water tight, protective containers and returned to the laboratory for further evaluation and testing.

2.4 Subsurface Conditions

The soils encountered consist of crushed stone, fills, sandy lean clay, sandy clay, clay with sand, clay, and soil shale over weathered shale rock. These near surface soils exhibit fairly low to fairly high plasticity characteristics. Rock materials (i.e., defined by standard penetration test refusal) were encountered in the indicated borings at the elevations shown in the following table:

Project No. 5316-3908 5 May 2, 2016

Elevation of Rock Material

Boring No.

Surface Elevation

(feet) Depth (feet)

Elevation (feet)

Rock Material

B-20 1360.51 13.50 1347.01 Weathered Shale

B-21 1359.16 11.00 1348.16 Weathered Shale

B-22 1360.31 11.00 1349.31 Weathered Shale

B-23 1361.35 11.00 1350.35 Weathered Shale

B-24 1359.28 18.00* 1341.28 Weathered Shale

*Although there is a standard penetration test refusal at 8.0 feet, we consider top rock at 18.0 feet because of the presence of soft weathered soil shale.

2.5 Groundwater

During drilling and at completion of drilling operations, groundwater was encountered in the indicated borings at the depths shown in the Elevation of Groundwater Table. Presence of water should be anticipated in any excavation. Water travelling through soil (subsurface water) is often unpredictable and may be present at shallow depths. Due to the seasonal changes in groundwater and the unpredictable nature of groundwater paths, groundwater levels will fluctuate. Therefore, it is necessary during construction to be observant for groundwater seepage in excavations in order to assess the situation and make necessary changes. We cannot assume responsibility for difficulties experienced during construction or for future operational problems due to elevation or volume of water encountered.

Based on the groundwater level data, recommended design groundwater depth is 2.33 feet

(El.=1356.83’).

Project No. 5316-3908 6 May 2, 2016

Elevation of Groundwater

Boring No.

Surface

Elevation (feet)

Depth At Completion

(feet)

Depth At 24 Hour

(feet)

Elevation (feet)

B-20 1360.51

5.90 - 1354.61

- 5.50 1355.01

B-21 1359.16 Dry - -

- 2.33 1356.83

B-22 1360.31 Dry - -

- 3.50 1356.81

B-23 1361.35 Dry - -

- 4.00 1357.35

B-24 1359.28

7.00 - 1352.28

- 3.00 1356.28

Project No. 5316-3908 7 May 2, 2016

Section 3

LABORATORY TESTING

Laboratory testing was performed in order to determine the strength and plasticity characteristics of the subsurface materials as well as confirm the soil classifications. General descriptions of the encountered soils together with visual and laboratory classifications and numerical values of the test results are on the boring logs included in Appendix “B.” A “Summary of Test Results” is included in Appendix “D.”

3.1 Tests Performed

• Moisture content tests were performed on twenty-one (21) split spoon, thin-walled tube, and bag samples, in accordance with ASTM D2216, to determine the in-situ moisture conditions.

• Density tests were performed on twenty (20) intact split spoon, and thin-walled tube samples in accordance with AASHTO T233.

• Atterberg limits tests were performed on eighteen (18) soil samples to determine the plasticity characteristics and swell potential of the soil. The tests were performed in accordance with ASTM D4318. Liquid Limits were determined using three-point method.

• Sieve analyses were performed on three (3) soil samples, in accordance with ASTM D2487, for aid in soil classification. These soils were classified according to the Unified Soil

Classification System (USCS) and the American Association of State Highway and

Transportation Officials (AASHTO) soil classification system.

• Laboratory pH and resistivity test were conducted on one (1) composite (B-21 and B-22 at top 5.0 feet) soil sample. ASTM D4972 was used to determine the pH of the soil, while

ASTM G57 (laboratory) method was employed to determine the electrical resistivity of the sampled soil. pH and resistivity tests determines the corrosion potential of the on-site soils regard to underground structures and pipelines. A result of a test is summarized under

Laboratory Testing Results in Section 4 of this report.

• Soluble sulfate content test was performed on one (1) composite (B-21 and B-22 at top 5.0 feet) soil sample in accordance with OHDL-49. A test result is summarized under Laboratory

Testing Results in Section 4 of this report.

Project No. 5316-3908 8 May 2, 2016

• Soluble chloride content test was performed on one (1) composite (B-21 and B-22 at top 5.0 feet) soil sample by colorimetric method using SMART2 Colorimeter. A test result is summarized under Laboratory Testing Results in section 4 of this report.

• Two (2) Modified Proctor test were conducted on composite sample (B-21 and B-22 at top

5.0 feet, and B-23 at top 5.0 feet), in accordance with ASTM D1557 testing procedures. The

Modified proctor test determines the relationship between moisture content and density at a specified compaction effort. A result of the modified proctor test is presented in Appendix

“D.”

• One (1) California Bearing Ratio (CBR) test was performed on composite sample (B-23 at top 5.0 feet) proposed parking/ drive areas to classify the suitability of the soils for use as a subgrade or base course material in pavement construction. The CBR test measures the relative strength of the soil under controlled moisture and density conditions. This test was performed in accordance with ASTM D1883. Results are presented as the test load corresponding to a given penetration (e.g., 2.5mm) driven by a standard load, expressed as percent, where the standard load is based on a standard sample of crushed stone. The results of a CBR test are presented in Appendix “D.”

• Four (4) unconfined compressive strength tests were conducted on thin-walled tube soil samples in accordance with ASTM D2166. The unconfined compressive strength as determined by this test, along with the results of the standard penetration test, is used to estimate the in-situ share strength of the various soils and rock encountered. The graph in

Appendix “D” depict the behavior of the tested soil under compression without confinement.

The unconfined compressive strengths of the soils and rock core samples were presented on the boring logs and in the “Summary of Laboratory Test Results” table in Appendix “D.”

• One (1) Oxidation-Reduction Potential of Soil test was conducted on composite sample (B-

21 and B-22 at top 5.0 feet) in accordance with ASTM G200. A test result is presented in

Appendix “D.”

• One (1) swell-consolidation test was performed on thin-walled tube sample at B-20 (3’-4’) in accordance with ASTM D4546 Method C testing procedure. A test result is summarized under Laboratory Testing Results in section 4 of this report.

Project No. 5316-3908 9 May 2, 2016

3.2 Laboratory Summary

General descriptions of the encountered soils together with visual and laboratory classifications and numerical values of the test results are on the boring logs and soil profile included in Appendix "B."

A "Summary of Test Results" is included in Appendix "D."

Project No. 5316-3908 10 May 2, 2016

Section 4

ENGINEERING EVALUATION AND RECOMMENDATIONS

4.1 Geological Information

The “Engineering Classification of Geologic Materials, Division Five,” Research and Development

Division of Oklahoma Highway Department, 1969, indicates that the project site is located over the

Terrace Deposits (Qts). This geologic formation is described therein as follows:

Terrace Deposits (Qts): These materials consist of sand, silt, clay, gravel, and/ or mixtures of these. Terrace materials occur adjacent to or near streams at higher elevations than the floor plain (bottom land). Like alluvium, these deposits are not all shown on the geologic unit maps.

The engineering properties of the unconsolidated materials are normally the same as the

“C” horizon of the overlying soil. Most Terrace deposits will have seepage where the underlying geologic material is less pervious.

According to the Geologic Map of the Hydrologic Atlas 6 of Oklahoma, “Reconnaissance of the

Water Resources of The Lawton Quadrangle, Southwestern Oklahoma,” by John S. Havens, U.S.

Geological Survey, Second Printing 1992, indicates that the project site is located over the

Hennessey Group (Phy). This geologic formation is described therein as follows:

Hennessey Group (Phy): Reddish-brown to gray shale with some tan sandstones, 130 to

200 feet thick (locally unconformable on Cambrian Igneous rocks).

4.2 Existing Site Conditions

Previous Construction Activity

It is our understanding that at the proposed site, there was previously building #171 located. Building

#171 was demolished prior to the construction of the new flight training Phase I facilities. New proposed facility addition footprint will overlap previous building #171.

Dewatering

Based on the field exploration data, groundwater was encountered at two (2) boring locations during and at completion of drilling operation and at all five (5) boring locations at 24 hours. Dewatering will be required during excavation. Sump pump(s) system may be used during excavation stage.

Project No. 5316-3908 11 May 2, 2016

Liquefaction Potential

Based on the field exploration data indicating no liquefied soils encountered, it is our opinion that the liquefaction potential is minimal.

Expansive, Dispersive or Collapsing Conditions

Based on the plasticity index and moisture content data. We estimate the potential vertical rise

(PVR) of the soils to be equal or less than1.00 inch. The characteristics of these soils are active for consideration of soil expansion for slab-on-grade. Dispersive and collapsing conditions were not found at the locations of the borings.

Evaluation of Karst Potential

Karst is generally a distinctive topography in which the landscape is largely shaped by the dissolving action of water on carbonate bedrock usually limestone, dolomite, or marble. This geological process, occurring over many thousands of years, results in unusual surface and subsurface features ranging from sinkholes, vertical shafts, disapprearing streams, and springs, to complex underground drainage systems and caves. Based on the in-situ investigation data and the research data of the geological information, karst features were not found. The level of the risk for development and/ or the presence of voids within the subsurface materials at this project site is very low.

Corrosion Potential

PH and resistivity test results indicate that the soils are slightly to moderately corrosive with regard to accelerated corrosion of metals. Details refer to the report section 4.5 – Laboratory Testing

Results.

4.3 Soil Conditions

The soils encountered in this subsurface investigation consist of crushed stone, fills, sandy lean clay, sandy clay, clay with sand, clay, and soil shale over weathered shale rock. These near surface soils exhibit fairly low to high plasticity characteristics. The cohesive soils were found to be firm to hard in consistency. The underlying weathered rock exhibits SPT refusal (i.e., SPT "N" value of 50 blows per 6 inches or less penetration).

The plasticity index (PI) of a soil indicates a soil’s potential to shrink or swell with changes in its moisture content. The near-surface soils at this site generally display fairly low to high plasticity characteristics and were found in a slightly moist to moist condition. Atterberg limits test results indicate that on-site plastic soils have PI’s up to 26. These soils should be considered active and should be expected to undergo significant volume change upon moisture variation.

Project No. 5316-3908 12 May 2, 2016

These soils are expected to undergo expansion upon moisture increase and, conversely, contraction upon moisture decrease. Oklahoma is well known for its heaving clays and the foundation problems associated with soil expansion and uplift pressures. These soil characteristics accompanied with the seasonal variability in soil moisture content caused by the regional climatic conditions often result in foundation and structural damage. Accordingly, the swelling characteristic of the soil is a primary concern and the Potential Vertical Rise (PVR) becomes an important factor in the foundation design of the proposed facility.

The maximum PVR value computed for this site is about 1.00 inch. The procedure used to predict the PVR was developed by Standard Testing based on AASHTO test method T258 and modified to incorporate our experience with actual Oklahoma soils. The displacement associated with the PVR is a relatively long term effect, associated with significant moisture changes in the soil, and applies to free surface conditions. A maximum PVR of 0.5 inch or less is generally considered tolerable for most structures.

Methods to reduce the actual swell include:

(1) removal of the expansive soil

(2) treatment of the soil to modify its plasticity

(3) application of pressure to resist the expansion (can be fill or structural loads)

(4) control of soil moisture during and after construction to minimize future moisture variations.

4.4 Seismic Site Class and Seismic Hazards

Based on the results of our investigation, this site is classified as Seismic Site Class C. This recommendation is based on the criteria given in Table 1613.5.2 of the International Building Code

(IBC) 2009, entitled "Site Class Definitions."

Following are the approximate mapped and design spectral acceleration parameters.

• The Approximate Mapped Spectral Acceleration for Short Periods, Sms=0.3;

• The Approximate Mapped Spectral Acceleration for a 1-Second Period, Sm1=0.17

• The Approximate Design Spectral Response Acceleration at Short Period, Sds=0.2

• The Approximate Design Spectral Response Acceleration at 1-Second, Period, Sd1=0.12

4.5 Laboratory Testing Results

pH and Resistivity Test Results

The pH and resistivity of the soil sample tested are summarized in the following table:

Project No. 5316-3908 13 May 2, 2016 pH and Resistivity Test Results

Boring No.

Sample

I.D.

Depth (feet) pH Resistivity (ohm-cm)

Corrosivity

B-21 & B-22 Composite 0-5.0 7.32 8,164 Slightly Corrosive

The pH and resistivity test results indicate that soils are slightly corrosive with regard to accelerated corrosion of metals.

Soluble Sulfate and Chloride Content Test Results

The soluble sulfate and chloride test results are included in the following table:

Soluble Sulfate and Chloride Content Test Results

Boring No. Sample I. D.

Depth (feet)

Sulfate Content (ppm)

Chloride Content (ppm)

B-21 & B-22 Composite 0-5.0 1,262 2.6

The results of the sulfate and chloride content tests indicate that Type I cement may be used for concrete and the sulfate levels are negligible in affecting lime stabilization of the soil. According to the National Lime Association’s publication entitled “Technical Memorandum: Guidelines for

Stabilization of Soils Containing Sulfates,” which can be found on their website at www.lime.org/ sulfate.pdf,” If the total level of soluble sulfates is below 0.3%, or 3,000 parts per million (ppm), by weight of soil, then lime stabilization should not be of significant concern.” corrosion of metals.

Modified Proctor Test Results

Modified proctor tests were conducted on two (2) composite soil samples in accordance with ASTM

D1557 testing method. The result is presented in the following table and are also presented in the

Appendix “D.”

Modified Proctor Test Results

Boring No.

Depth (feet)

USCS AASHTO

Maximum Dry Density

(pcf)

Optimum Moisture

B-23 0-5.0 CL A-6(9) 123.8 10.4

B-21 & B-22 0-5.0 CL A-6(14) 121.5 11.5

Project No. 5316-3908 14 May 2, 2016

California Bearing Ratio (CBR) Test Results

California bearing ratio (CBR) of laboratory-compacted soil was conducted on a composite soil in accordance with ASTM D1883 testing method. The result is presented in the following table and is also presented in Appendix “D.”

CBR Test Results

Boring No. Sample I. D.

Depth

(feet) Soil Type CBR

Estimated ks

(pci)

B-23 Composite 0-5.0 Sandy Lean Clay 5.4 148

Unconfined Compressive Strength of Soil Test Results

Unconfined compressive strength tests were conducted on thin-walled tube soil samples in accordance with ASTM D2166 testing method. The results are presented in the following table and are also presented in Appendix “D.”

Unconfined Compressive Strength Test Results (qu)

Boring No.

Depth

(feet)

Moisture

Content

Dry Density

(pcf) qu

(tsf)

Strain

B-20 4.0-6.0 14.1 107 1.47 2.78

B-24 2.0-4.0 16.8 116 2.50 5.67

B-24 4.0-6.0 21.6 107 3.33 10.47

B-24 6.0-7.5 22.2 104 2.55 3.49

Swell-Consolidation Test Results

One (1) swell-consolidation test was performed with ASTM D4546 Method C. Based on the result of the test, the percent swell of the sample is negligible i.e. 0.02% (approximately) for B-20(3.0-4.0 feet) at vertical overburden pressure. Moisture contents of the tested sample measured before the test was 16.7% and after test was 16.1%. The recompression index (Cr) and compression index

(Cc) obtained for the soils are listed in the following table. The recompression and compression indexes were determined using “Technical Engineering and Design Guides as Adapted from the US

Army Corps of Engineers, No. 9: Settlement Analysis” (ASCE, 1994).

Project No. 5316-3908 15 May 2, 2016

Recommended Swell Consolidation Test Parameters

Boring

I.D.

Overburden

Pressure

Po(tsf)

Pre-consolidation

Pressure

Pc(tsf)

Recompression

Index

Cr

Virgin Compression

Index

Cc

Swell

B-20(3-4’) 0.18 2.1 0.0212 0.1345 0.02

We estimate that there is no swelling of the foundation soil. However at B-21 there are some expansive soils at upper 2 feet which results Potential Vertical Rise up to 1.00 inches. We recommend to follow “Building Pad Construction” section of this report for slab-on-grade construction.

4.6 Earthwork Recommendations

Building Pad Construction

It is understood that the finished floor elevation is planned at 1364.75 feet. A critical geotechnical consideration at this site is the swelling soils. If slab-on-grade construction is to be used for this site, either soil stabilization or construction of an inert fill building pad is advisable.

The amount of ground surface movement that can be tolerated by the structure should be evaluated by the designer (a value of 0.50 inch or less may be used for most structures) and the corresponding amount of removal and replacement or over ground fill should be performed as indicated in the following options:

Option 1: Cut and Fill

• Remove the required amount of existing soil (see following table) and replace that soil with inert fill, meeting all requirements given herein, or native soil stabilized with lime or fly ash to achieve a primary swell of no more than 1.0 percent when tested in accordance with ASTM

D4546 Method B with a vertical stress equal to the anticipated in-situ vertical stress.

Cut and Fill Building Pad Requirements

Depth of Removal and Replacement Soil (feet)*

Estimated Potential Vertical Rise (PVR) (inches)

0.0 1.00

1.0 0.63

2.0 0.31

* - Below existing site grade

Project No. 5316-3908 16 May 2, 2016

Option 1 Case: Final Grade Elevation equal or lower than Existing Grade Elevation

Final Grade Elev.=1364.75

Existing Grade Elev.=1363.75

Based on the above table, it is required to cut down 2-ft to reduce the PVR to less than ½-inch, so the final cut elevation should be Elev.=1361.75 and then fill up 4-ft inert fills to the final grade elevation (Elev.=1364.75).

or

Option 2: Fill Only

• Place the required amount or more of inert fill (see following table), meeting all requirements given herein, over the native soils.

Over Ground Inert Fill Building Pad Requirements

Depth of Over Ground Inert Fill Building Pad

(feet)**

Estimated Potential Vertical Rise (PVR) (inches)

0.0 1.00

1.0 0.74

2.0 0.53

3.0 0.41

** - Above existing site grade

Option 2 Case: Final Grade Elevation higher than Existing Grade

Final Grade Elev.=1364.75

Existing Grade Elev.=1363.75

Based on the above table, if you only fill 1.0 foot inert fill the PVR will be 0.74 inches, so you need to reduce (0.74 inch – 0.50 inch = 0.24 inch). To determine the thickness of cut and fill to reduce

PVR to equal or greater than 0.24-inch, you would need to refer to first table it is required to cut down one foot to reduce the PVR to (1.0-inch – 0.63 inch = 0.37-inch which is for this case you can cut down one foot of existing subgrade soils and fill 2 feet inert fill up to the final grade elevation (Elev.=1364.75).

Inert Fill Requirements

Only nonplastic to fairly low plasticity on-site soils or imported inert fill should be used for fill under structures. Fills should meet the following requirements:

Satisfactory Materials Satisfactory materials comprise any materials classified by ASTM D2487 as SC, SW-SC, SP-SC, Project No. 5316-3908 17 May 2, 2016

CL, GC, GM-GC, and GP-GC with the requirements below:

Amount finer than 2 inch sieve Amount finer than No. 200 sieve Liquid Limit Plasticity Index (PI)

= 100% = 12% minimum and, if PI<7, 60% maximum = 40 maximum = 4 to 12 maximum

Unsatisfactory Materials

Materials which do not comply with the requirements for satisfactory materials are unsatisfactory.

Based on the field and laboratory testing data, the on-site fairly low plasticity to medium plasticity soils does not meet satisfactory materials requirements as inert fill. However, these soils may be mixed with lime additive to reduce PIs to be greater than 4 and less than 12. Additional laboratory testing will be necessary to determine the percentage of additive required during construction stage.

Subgrade Preparation

The existing subgrade should be:

• Stripped of vegetation, topsoil, fills and any other deleterious materials,

• over-excavated to the required depth to reduce PVR to ½ inch referring the cut and fill building pad requirements and/ or overground inert fill building pad requirements tables, and extended to at least three (3) feet beyond building footprint,

• proofrolled, including removing and replacing any soft material which exhibits permanent subgrade deformation exceeding 0.5 inch when traversed by a loaded truck with a rear axle load of approximately 16,000 lbs./axle, and

• tested for moisture and density and, if deficient, scarified to a depth of 8 inches, moisture conditioned and compacted to 95 percent or more of modified Proctor maximum dry density (ASTM D1557).

Removal of soft subgrade should not exceed a 3 foot depth below final top of subgrade elevation, nor extend below the static groundwater elevation. If such a depth is reached without encountering stable subgrade conditions, 12 inches of ODOT Type A or Type B aggregate base should be placed in the bottom of the overexcavated area and suitable fill material placed and compacted to bring the subgrade to design elevation.

Compaction Requirements

All fill in the structural areas should be:

Project No. 5316-3908 18 May 2, 2016

• compacted to at least 95 percent or more of Modified Proctor maximum dry density

(ASTM D1557) at a moisture content within -3% to +1% of the optimum for A-6.

• compacted to at least 95 percent or more of modified Proctor maximum dry density

(ASTM D1557) at a moisture content near optimum for ODOT Type A or Type B aggregate base.

• placed in lifts not to exceed eight (8) inches in compacted thickness.

• tested for field density for each lift of fill at frequencies of every 5,000 sq. ft. in areas under structure and every 20,000 sq.ft in areas under pavement.

Moisture should be maintained up until the placement of concrete in structural areas to prevent shrinkage (and subsequent post-construction swell) of the soil.

Drainage

The ground immediately adjacent to the foundation shall be sloped away from the building at a slope of not less than 6 inches vertical fall in the first 10 feet measured perpendicular to the face of each wall.

Trees and large bushes for landscaping should not be permitted within this 10-foot zone adjacent to the building. General site slopes, drainage swales, or storm drains shall be constructed to provide

1.0 percent slope, or more, along drainage paths which serve to discharge storm water from the site. If surface soil should be left exposed (e.g., flower beds) near the structure foundation, then it is suggested that efforts be taken to maintain such areas at a constant moisture in order to avoid swell/shrinkage of the soil that will affect the foundation system.

If a non-expansive (Inert fill) building pad is constructed such that it extends below the adjacent higher plasticity soils, the bottom of such excavation shall be cut at a slope of not less than 1.0 percent to provide a subsurface sump. Drainage shall be provided from this sump in the base of the non-expansive building pad by an underdrain with a slope of at least 1.0 percent discharging either to daylight or to a permanent, automated sump pump system. The underdrain at the sump shall extend below the excavation and shall consist of a perforated nonmetallic underdrain conduit

(ODOT 726.02(b)6), 4.0 inches diameter or larger, wrapped in drainage geotextile (ODOT 712.03) and surrounded by at least 6 inches of coarse cover aggregate (ODOT 703.04) on all sides.

4.7 Foundation Recommendations

Considering the soils encountered and based on the test results of this exploration, the following foundation design parameters are recommended for the indicated foundation systems:

Project No. 5316-3908 19 May 2, 2016

• Footing Foundation System

Shallow foundations (e.g. spot or strip footings) may be used for support the structure. Footings must be placed a minimum of 2.0 feet below finished grade to provide adequate protection from frost action. Footings may be used with an allowable net bearing capacity of 2,500 psf bearing in either native stiff clayey soils, or compacted inert fill/ or stabilized subgrade as specified in the Earthwork

Recommendations section of this report. The allowable net bearing capacity includes a factor of safety of 3.0. Footings should have a width of at least 16 inches.

Ultimate resistance to lateral sliding at the bottoms of footing may be calculated based on the coefficient of friction of 0.35 for both inert fills and native clayey soils.

Sliding resistance may also include the ultimate passive resistance which can be calculated using an equivalent fluid weight of 200 pcf for a rectangular distribution.

A factor of safety of at least 1.5 should be used with stability calculations involving lateral earth pressures.

Continuous footings and/ or spot footings are expected to undergo no more than

1.0 inch settlement when designed for the recommended bearing pressure.

Differential settlement would be less than ¾ inch across the site.

• Pier Foundation System

Structures may be designed for the supported by drilled cast-in-place concrete piers founded 2.0 feet or more below the depths indicated in the "Elevation of Rock

Material" table provided in Section 2.4 of this report. Using this type of foundation, each column is supported on a single drilled pier and the building walls are placed on grade beams supported by a series of piers. Loads applied to the piers are transmitted to the rock partially through skin friction along the sides of the pier and partially through end bearing pressure.

All drilled piers should:

• extend at least 2.0 feet or at least one (1) pier diameter, whichever is deeper, below the depths indicated in the "Elevation of Rock Material" table provided in section 2.4 of the report,

• have an aspect ratio (length/ diameter) of four (4) or more,

• have a spacing between individual piers of three diameters or more (Clear

Spacing), Project No. 5316-3908 20 May 2, 2016

• be adequately reinforced with the reinforcement extending into the grade beams and/ or pier caps, and

• have a minimum diameter of 18 inches.

Piers may be designed using the following allowable and net bearing capacities and skin friction at various depths range for that portion of the pier in direct contact with the weathered shale rock formation:

First Design Profile

Drilled Pier Capacities (Borings B-20/ B-21/ B-22)

Depths Range

(feet)

Allowable Net Bearing

Capacity

(psf)

Allowable Skin Friction

Capacity

(psf)

Factor of Safety

0-6.0 - 270 3.0

6.00-8.00 4,000 400 3.0

8.00-11.00 8,000 600 3.0

11.00-15.00…