B3c_IFB_Amdt_2,_18B0009.pdf

AMENDMENT OF SOLICITATION/MODIFICATION OF CONTRACT

Except as provided herein, all terms and conditions of the document referenced in Item 9A or 10A, as heretofore changed, remains unchanged and in full force and effect.

15A. NAME AND TITLE OF SIGNER (Type or print)

30-105-04 EXCEPTION TO SF 30

APPROVED BY OIRM 11-84

STANDARD FORM 30 (Rev. 10-83) Prescribed by GSA

FAR (48 CFR) 53.243

The Solicitation for Military Working Dog Facility, Multiple Buildings Dyess Air Force Base, Texas, is amended as follows:

See SF30 Continuation Sheet(s)

NOTE: Proposal Receipt date is changed to 7 June 2018; at 10:00 a.m.CDT.

1. CONTRACT ID CODE PAGE OF PAGES

J 1 2

16A. NAME AND TITLE OF CONTRACTING OFFICER (Type or print)

16C. DATE SIGNED

BY

16B. UNITED STATES OF AMERICA 15C. DATE SIGNED 15B. CONTRACTOR/OFFEROR

(Signature of Contracting Officer) (Signature of person authorized to sign)

8. NAME AND ADDRESS OF CONTRACTOR (No., Street, County, State and Zip Code) X 9A. AMENDMENT OF SOLICITATION NO.

W9126G18B0009

X 9B. DATED (SEE ITEM 11)

01-May-2018

10B. DATED (SEE ITEM 13)

11. THIS ITEM ONLY APPLIES TO AMENDMENTS OF SOLICITATIONS

X The above numbered solicitation is amended as set forth in Item 14. The hour and date specified for receipt of Offer is extended, X is not extended.

Offer must acknowledge receipt of this amendment prior to the hour and date specified in the solicitation or as amended by one of the following methods:

(a) By completing Items 8 and 15, and returning copies of the amendment; (b) By acknowledging receipt of this amendment on each copy of the offer submitted;

or (c) By separate letter or telegram which includes a reference to the solicitation and amendment numbers. FAILURE OF YOUR ACKNOWLEDGMENT TO BE RECEIVED AT THE PLACE DESIGNATED FOR THE RECEIPT OF OFFERS PRIOR TO THE HOUR AND DATE SPECIFIED MAY RESULT IN REJECTION OF YOUR OFFER. If by virtue of this amendment you desire to change an offer already submitted, such change may be made by telegram or letter, provided each telegram or letter makes reference to the solicitation and this amendment, and is received prior to the opening hour and date specified.

12. ACCOUNTING AND APPROPRIATION DATA (If required)

13. THIS ITEM APPLIES ONLY TO MODIFICATIONS OF CONTRACTS/ORDERS.

IT MODIFIES THE CONTRACT/ORDER NO. AS DESCRIBED IN ITEM 14.

A. THIS CHANGE ORDER IS ISSUED PURSUANT TO: (Specify authority) THE CHANGES SET FORTH IN ITEM 14 ARE MADE IN THE

CONTRACT ORDER NO. IN ITEM 10A.

B. THE ABOVE NUMBERED CONTRACT/ORDER IS MODIFIED TO REFLECT THE ADMINISTRATIVE CHANGES (such as changes in paying office, appropriation date, etc.) SET FORTH IN ITEM 14, PURSUANT TO THE AUTHORITY OF FAR 43.103(B).

C. THIS SUPPLEMENTAL AGREEMENT IS ENTERED INTO PURSUANT TO AUTHORITY OF:

D. OTHER (Specify type of modification and authority)

E. IMPORTANT: Contractor is not, is required to sign this document and return copies to the issuing office.

14. DESCRIPTION OF AMENDMENT/MODIFICATION (Organized by UCF section headings, including solicitation/contract subject matter where feasible.)

10A. MOD. OF CONTRACT/ORDER NO.

2. AMENDMENT/MODIFICATION NO. 5. PROJECT NO.(If applicable)

6. ISSUED BY

3. EFFECTIVE DATE

16-May-2018

CODE

US ARMY ENGINEER DISTRICT, FORT WORTH

ATTN: CESWF-CT

819 TAYLOR ST, ROOM 2A19

P.O. BOX 17300

FORT WORTH TX 76102-0300

W9126G 7. ADMINISTERED BY (If other than item 6)

4. REQUISITION/PURCHASE REQ. NO.

CODE

See Item 6

FACILITY CODE CODE

EMAIL: TEL:

W9126G18B0009

SECTION SF 30 BLOCK 14 CONTINUATION PAGE

SUMMARY OF CHANGES

CHANGES TO PROPOSAL RECEIPT DATE

1. Proposal Receipt Date: Change the proposal receipt date from "31 May 2018, 10:00 a.m. local time" to "7 June 2018, 10:00 a.m. local time "

CHANGES TO DIVISION 00 - PROCUREMENT AND CONTRACTING REQUIREMENTS

2. Section 00 22 00 SEALED BIDDING INSTRUCTIONS, each page bearing the notation W9126G18B009-0002.

APPENDICES

3. Appendices are being added to the Solicitation, each bearing the notation W9126G18B0009-0002.

APPENDIX A MWD FACILITY GEOTECHNICAL REPORT

APPENDIX B DYESS AFB ASB SURVEY REPORT

APPENDIX C MERRICK DYESS AFB HAZMAT REPORT

APPENDIX D MERRICK DYESS AFB WORKING DOG FACLEAD-BASED PAINT SURVEY

APPENDIX E MERRICK DYESS AFB WORKING DOG FAC MOLD REPORT

End of Summary of Changes

SECTION 00 22 00

SEALED BIDDING

INSTRUCTIONS

PART I – GENERAL INFORMATION

1. INQUIRIES

OFFEROR'S QUESTIONS AND COMMENTS

All questions and/or comments are to be submitted via ProjNet.

Bidder Inquiry in ProjNet at http://www.projnet.org/projnet

To submit and review bid inquiry items, bidders will need to be a current registered user or self-register into system. To self-register go to web page, click BID tab select Bidder Inquiry, select agency USACE, enter Key for this solicitation listed below, and your e-mail address, click login. Fill in all required information and click create user. Verify that information on next screen is correct and click continue.

From this page you may view all bidder inquiries or add inquiry.

Bidders will receive an acknowledgement of their question via email, followed by an answer to their question after it has been processed.

The Solicitation Number is: W9126G18B0009 The Bidder Inquiry Key is: S5D6X3-G9C7J8

Last day to submit ProjNet questions is 5 calendar days prior to bid closure date in order to ensure adequate time is allotted to form an appropriate response and amend the solicitation, if necessary.

Offerors are requested to review the specification in its entirety, review the Bidder Inquiry System for answers to questions prior to submission of a new inquiry.

The call center operates weekdays from 8AM to 5PM U.S. Central Standard Time Zone (Chicago).

The telephone number for the Call Center is 800-428-HELP.

NOTE: Offers received will be publicly opened at the following location:

US Army Engineer District, Fort Worth 819 Taylor St, Room 4C03 Fort Worth, TX 76102

10:00 AM (CDT)

Oral explanations or instructions are not binding. Any information given to an Offeror which impacts the solicitation and/or offer will be given in the form of a written amendment to the solicitation.

W9126G18B0009, AMENDMENT 0002

http://www.projnet.org/projnet

2. INSTRUCTIONS TO OFFERORS

a. All offers MUST be received, in Original, no later than <AM#0002> 31 May 2018 7 June 2018

<AM#0002> at 10:00 AM (CDT).

• Submission Location:

U.S. Army Corps of Engineers, Fort Worth District ATTN: Kristi Pagan Federal Building 819 Taylor Street, Rm 2A17 Fort Worth, Texas 76102-0300

• Offer envelope shall clearly state “Invitation for Bid” and include the Invitation for Bid number, Invitation for Bid Title, Bidder name and contact information (to include email address), Bid opening date, and Bid opening time.

• Offers must be presented to and received by the front desk attendant through any viable means of delivery.

• Offers must include the completed SF 1442 (in accordance with FAR 52.214-18), Acknowledgement of all amendments, completed CLIN schedule, and original Bid Bond.

b. OFFERS BY TELEGRAPH. Offers received by telegraph, modifications thereto, or cancellations of offers will or will not be accepted.

c. FACSIMILE OFFERS. Facsimile offers, modifications thereto, or cancellations of offers will or will not be accepted.

d. EMAIL. Modifications and cancellations of offers will or will not be accepted. Only the Original submitted bid will be accepted by the Government.

e. RESPONSIBILITY. Award will be made to the lowest, responsible bidder whose bid, conforming to the invitation for bids, will be the most advantageous to the Government. To be determined responsible, the apparent low bidder shall:

(1) Have adequate financial resources to perform the contract, or the ability to obtain them. The contractor will be required to provide the Name of the Financial Institution, POC, and phone number.

(2) Have a satisfactory performance record. The contractor shall have no performance annotated with an individual rating of less than SATISFACTORY.

(3) Have a satisfactory record of integrity and business ethics. Awardee will be required to provide at least three (3) references for like work, to include Business Name, Point of Contact, and telephone number.

(4) Have the necessary organization, experience, accounting and operational controls, and technical skills, or the ability to obtain them (including, as appropriate, such elements as production control procedures, property control systems, quality assurance measures, and safety programs applicable to materials to be produced or services to be performed by the prospective contractor and subcontractors).

(5) Have the necessary production, construction, and technical equipment and facilities, or the ability to obtain them; and

(6) Be otherwise qualified and eligible to receive an award under applicable laws and regulations

f. NOTIFICATION OF UNSUCCESSFUL BIDDERS. All contract award information for this solicitation will be published electronically on FedBizOpps (FBO) at www.fbo.gov/ Solicitation Number W9126G18B0009. Written unsuccessful bidder letters will not be issued.

g. PROCEDURES FOR ENTERING FEDERAL BUILDING. All persons, not in possession of a Government issued Common Access Card (CAC) or PIV Card, must enter through the Taylor Street entrance and go through the Public Security Screening Station. Personal bags and persons will be screened by the Federal Protection Service Guards. No weapons allowed except for credentialed Law Enforcement Officers.

h. PARKING. There is paid public parking available in the downtown Fort Worth area.

3. PREPROPOSAL CONFERENCE / SITE VISIT

SITE VISIT. See FAR clause 52.236-27 SITE VISIT (CONSTRUCTION) (FEB 1995) –

ALTERNATE I (FEB 1995)

IMPORTANT NOTES. (1) Remarks and explanations addressed during the conference shall not qualify or alter the terms and conditions of the solicitation. (2) The terms and conditions of the solicitation remain unchanged unless the solicitation is formally amended in writing.

http://www.fbo.gov/

March 17, 2016

Merrick & Company 401 E. Sonterra Blvd., Ste 250 San Antonio, Texas 78258 Attn: Ms. Tammy Johnson, PMP

Re: Geotechnical Engineering Study Proposed Working Dog Facility Ammo Road Dyess AFB, Texas PSI Project No. 0312-1290

Dear Ms. Johnson, Professional Service Industries, Inc., (PSI) is pleased to submit our report of Geotechnical Engineering Study for the referenced project. This report includes the results of field and laboratory testing, and recommendations for foundation and pavement design, as well as general site development.

We appreciate the opportunity to perform this Geotechnical Study and look forward to continuing participation during the design and construction phases of this project. If you have any questions pertaining to this report, or if we may be of further service, please contact our office.

Respectfully submitted, Professional Service Industries, Inc.

J.R. Eichelberger, III, P.E.

Department Manager Geotechnical Services

Professional Service Industries, Inc. • Three Burwood Lane • San Antonio, TX 78216 • Phone 210/342-9377 • Fax 210/342-9401

GEOTECHNICAL ENGINEERING STUDY

Proposed Working Dog Facility Ammo Road

Dyess AFB, Texas

PSI Project No.: 0312-1290

PREPARED FOR

401 E. Sonterra Blvd, Ste 250

San Antonio, Texas 78258

March 17, 2016

BY

PROFESSIONAL SERVICE INDUSTRIES, INC.

3 Burwood Lane

San Antonio, Texas 78216 Ph (210) 342-9377 Fax (210) 342-9401

Texas Firm Registration F-3307

Luis Perez-Milicua, E.I.T. Dexter Bacon, P.E.

Project Engineer Chief Engineer Geotechnical Services

3/17/2016

TABLE OF CONTENTS

Page No.

PROJECT INFORMATION

• Project Authorization

• Project Description

• Purpose and Scope of Services

SITE AND SUBSURFACE CONDITIONS

• Site Description

• Site Geology

• Subsurface Conditions

• Groundwater Information

EVALUATION AND RECOMMENDATIONS

• Geotechnical Discussion

• Potential Vertical Rise

• Building Pad Preparation

• Select Fill Recommendations

• Expansive Soil Considerations

• General Site Preparation Outside Building Pad

• Compaction and Testing Requirements

• Slab-On-Grade Foundation Recommendations

• Adjacent Sidewalks and Flatwork

• Seismic Design Considerations

• Pavement Recommendations

• Pavement Design Discussion

• Flexible Pavement Recommendations

• Rigid Pavement Recommendations

• Pavement Material Specifications

CONSTRUCTION CONSIDERATIONS

• Moisture Sensitive Soils/Weather Related Concerns

• Drainage Concerns

• Excavations

REPORT LIMITATIONS

APPENDIX

Site Vicinity Map Boring Location Plan Boring Logs Key to Terms and Symbols Used on Logs

Proposed Working Dog Facility PSI Project No. 0312-1290 Ammo Road in Dyess Air Force Base; Del Rio, Texas March 17, 2016

PROJECT INFORMATION

Project Authorization

Professional Service Industries, Inc., (PSI) has completed a geotechnical study for the proposed Working Dog Facility to be located at Ammo Road in Dyess Air Force Base (AFB), Texas. PSI’s services were authorized by Ms. Tammy Johnson with Merrick & Company through Subcontract No.

SUBK-5418-A62000-001 and Work Order No. 9126-PSI02 dated March 15, 2016.

Project Description

It is understood that the currently proposed development consists of a new combination indoor/outdoor Military Working Dog (MWD) Kennel, and MWD Support Facility for personnel with covered walkway connecting buildings. Facilities to be CMU block construction with reinforced concrete foundation and slab, standing seam metal roof, and all necessary and associated site work and utilities. Site work includes paving, sidewalks, security fencing and utilities extensions. The project includes demolition of the existing MWD Kennel Building 9101 and MWD Support Building 9106. The facilities will be designed as permanent construction in accordance with the DoD Unified Facilities Criteria (UFC) 1-200-01, General Building Requirements, and UFC 1-20-02, High Performance and Sustainable Building Requirements. Estimated air conditioning is 25 tons.

The project will be located northeast of the existing MWD Facility on Ammo Road within Dyess AFB, Texas. The latest site plan features two buildings with a footprint between 2,800 and 3,300 square feet and will be one-story in height. The Finished Floor Elevation (FFE) of the proposed structures have not been established at the time of this report. We have assumed that the FFE will be within 1 foot of existing grade. Information regarding the anticipated maximum column structural loads were not provided to PSI at the time of this report.

Automobile parking areas with associated access drives will be constructed as part of the planned development. Information regarding traffic loading conditions was not provided to PSI. Rigid and flexible pavement systems are under consideration for the planned development.

The geotechnical recommendations presented in this report are based on the available project information, proposed building and pavement locations, and the subsurface materials described in this report. If any of the noted information is incorrect, please inform PSI in writing so that we may amend the recommendations presented in this report. PSI will not be responsible for the implementation of our recommendations when we are not notified of changes in the project.

Purpose and Scope of Services

The purposes of this study are to explore the subsurface conditions at the site and provide an evaluation of acceptable foundation and pavement systems for the proposed site improvements.

Our scope of services included drilling a total of four (4) soil borings throughout the proposed development. Our services also included performing selected laboratory testing and preparing this geotechnical report. This report briefly outlines the available project information, describes the site and subsurface conditions, and presents recommendations regarding the following:

General site development, subgrade preparation and building pad construction.

Foundation types, depths, allowable bearing capacities and an estimate of potential settlement.

Flexible and rigid pavement recommendations and pavement subgrade preparation.

Comments regarding factors that may impact construction and performance of the proposed construction.

The scope of services did not include an environmental assessment for determining the presence or absence of wetlands, or hazardous or toxic materials in the soil, bedrock, surface water, groundwater, or air on or below, or around this site. Any statements in this report or on the boring logs regarding odors, colors, and unusual or suspicious items or conditions are strictly for informational purposes.

PSI did not provide any service to investigate or detect the presence of moisture, mold or other biological contaminants in or around any structure, or any service that was designed or intended to prevent or lower the risk of the occurrence of the amplification of the same. Mold is ubiquitous to the environment with mold amplification occurring when building materials are impacted by moisture.

SITE AND SUBSURFACE CONDITIONS

Site Description

The site for the proposed new structures is located northeast of the existing MWD Facility on Ammo Road in Dyess AFB, Texas. The site is currently undeveloped and relatively flat. The location of all of the proposed structures based on the latest plan that was provided to PSI is generally illustrated in the following figure.

Proposed grades or an elevation survey was not provided to PSI at the time of this report. Elevations for the performed boring locations are not included in the boring logs and depths are referenced from existing site grade at the time of our field exploration.

Site Geology

We reviewed the Abilene Sheet of the Geologic Atlas of Texas 1972 to determine the geologic setting of the project site and surrounding areas. The Geologic Atlas of Texas was developed by the Bureau of Economic Geology at The University of Texas using aerial photography, data from various oil and gas exploration companies, and very limited ground reconnaissance. Our review indicates that the project site is mapped as being located within the Clear Fork Group (Pcf). The Abilene Sheet generally describes the Leona Formation as consisting of mudstone, limestone, dolomite and siltstone. This formation is known to contain highly expansive soils for the upper material in the project area.

Subsurface Conditions

The site subsurface conditions were explored by drilling a total of four (4) soil borings. The boring locations and logs of borings are as generally presented in the Appendix of this report. The number of borings, boring locations and boring depths were selected by PSI. The borings were located in the field by PSI personnel by using a handheld GPS device. The borings were advanced utilizing solid flight auger drilling methods and soil samples were routinely obtained during the drilling process.

Drilling and sampling techniques were accomplished in general accordance with ASTM procedures.

Selected soil samples were tested in the laboratory to determine material properties for use in our evaluation of the project site. Laboratory testing and soil classification were accomplished in general accordance with ASTM procedures.

The soil stratigraphy as identified by the boring logs and the soil profiles indicate that the soils are reasonably consistent across the project area with some minor variations in thickness, depth and type of the strata encountered. The generalized subsurface conditions encountered at our boring locations consist primarily of Fat Clay (CH) with Sand, Clayey Sand (SC) and Sandy Lean Clay (CL) major strata to the maximum explored depths of 25 feet below the existing ground surface. The subsurface conditions at the site, and below any surficial or pavement materials, generally consist of the following. Please note that not all strata were encountered in every boring.

Stratum Range of Depth, ft. Stratum Description and Classification

I 0 – (10 to 13) FAT CLAY (CH), stiff to very stiff, dark brown

II (10 to 13) – (16 to 22)

CLAYEY SAND (SC), medium dense, tan

- encountered in Boring B-1 from 13 to 15 feet.

- encountered in Boring B-2 from 13 to 20 feet.

- not encountered in Boring B-3.

III (16 to 22) - 25 SANDY LEAN CLAY (CL), very stiff, dark brown

The above subsurface descriptions are of a generalized nature to highlight the major subsurface stratification features and material characteristics. The boring logs included in the Appendix should be reviewed for specific information at individual boring locations. These records include soil descriptions, stratifications, penetration resistances, locations of the samples and laboratory test data. The stratifications shown on the boring logs only represent the conditions at the actual boring locations and were estimated to the nearest ½ foot. Variations will occur and should be expected at locations away from boring locations. The stratifications represent the approximate boundary between subsurface materials and the actual transitions may be gradual. Water level observations made during field operations are also shown on these boring logs. The portions of samples that are not altered or consumed by laboratory testing will be retained for 60 days from the date of this report and will then be discarded.

Groundwater Information

The borings were advanced using dry drilling techniques to their full depths, enabling the possibility of detection of the presence of groundwater during drilling operations. Groundwater was encountered in Boring B-2 at a depth of 18 feet below existing ground. A second groundwater reading was performed upon completion of drilling and it was measured at 17.1 feet below existing ground. Upon completion of groundwater observations, the boreholes were backfilled with native soil cuttings.

Groundwater levels are influenced by seasonal and climatic conditions which generally result in fluctuations in the elevation of the groundwater level over time. In addition, perched water can exist within the overburden soils, especially following periods of rainfall. Granular soils were encountered in Boring B-1 and B-2. These granular materials will transmit groundwater readily and thus will likely result in fluctuating groundwater levels. Therefore, the foundation contractor should check the groundwater conditions just prior to foundation excavation activities. Specific information concerning groundwater is noted on each boring log presented in the Appendix of this report.

EVALUATION AND RECOMMENDATIONS

Geotechnical Discussion

The foundations being considered to provide support for any structure must satisfy three completely independent engineering criteria with respect to the stratigraphy at the site. One criterion is that the foundation system must be designed with an appropriate factor of safety to reduce the possibility of a bearing capacity failure of the soils underlying the foundation. The second criterion is that movement beneath the foundation system due to compression (consolidation) or expansion (swell) of the underlying soils must be within tolerable limits for the structure. The third criterion is that differential movements should be within the tolerable limits for the structure.

The field and laboratory data acquired during this study indicate that fat clay soils encountered at the site are volumetrically unstable. These soils generally have a high potential to experience volumetric changes with fluctuations in moisture content. The intermediate strata of clayey sand are granular in composition and are not expected to experience significant volumetric changes with fluctuations in moisture content. The proposed structures can be supported on a stiffened beam and slab-on-grade foundation system provided that a portion of the existing soils are removed and replaced with low plasticity Select Fill material.

If grade-supported floor slabs are used, the relatively high expansive potential of the subsurface soils must be addressed in the design and construction in order to reduce the potential of soil-induced movements and potential resulting distress. Reduction in expansive potential for ground supported floor slab systems can typically be achieved by removing a portion of the expansive soils in the building area and constructing building pads with relatively low-expansive potential select fill material.

However, it should be understood that significant earthwork will be required at this site to reduce the potential of soil induced movements to typically acceptable values.

The following design recommendations have been developed based on the previously described project characteristics and subsurface conditions encountered. If there are any changes in these project criteria, including project location on the site, a review must be made by PSI to determine if any modifications in the recommendations will be required. The findings of such a review should be presented in a supplemental report. Once final design plans and specifications are available, a general review by PSI is strongly recommended as a means to check that the conditions assumed in the project description are correct and that the earthwork and foundation recommendations are properly interpreted and implemented.

Potential Vertical Rise

The estimated Potential Vertical Rise (PVR) valves have been calculated using the Texas Department of Transportation Method TEX-124E and utilizes the moisture contents and Atterberg Limit test results of the soils within the seasonally active zone. This method is based on a proposed floor system applying a sustained surcharge load of approximately 1.0 pound per square inch on the subgrade materials.

Based on our laboratory test results, the calculated PVR in the area of the proposed development is estimated at about 4 inches in the present condition. These estimates represent the vertical rise that can be experienced by relatively dry subgrade soils if they are subjected to conditions that allow them to significantly increase in moisture content, such as poor drainage. The actual movement of the subsoils is dependent upon their degree of increased moisture content. Differential vertical movements can equal the expected total movements. Undercutting a portion of the existing soils and placing compacted, low-expansive select fill between the natural soils and the floor slab can reduce the PVR. In order to reduce the PVR to an acceptable value of a 1-inch, it is required to remove 5.0 feet of the existing soils and replace with 5.0 feet of compacted Select Fill.

Another widely accepted method to estimate the magnitude of anticipated expansive soil movement is to utilize procedures outlined in Post-Tensioning Institute’s (PTI) “Design of Post-Tensioned Slabs-on-Ground, 3rd Edition”. The soil movement from a wet to dry (shrinkage) or dry to wet (heave) can be estimated utilizing Atterberg limits, grain size and soil suction information. Additionally, climatic characteristics are estimated for a specific geographic location. The computer program VOLFLO 1.5 is based on PTI procedures and is utilized to estimate potential shrink/swell movements for the existing and improved conditions. Based on this method, a potential swell of 3¾ inches was estimated for this location.

Any grade supported foundation or floor slab constructed at this site should be expected to undergo some differential vertical movements. In this general area, most structural and geotechnical engineers consider a PVR of one (1) inch or less to be within acceptable tolerances. However, this movement does not take into consideration the movement criteria required or perceived by the facility owner or occupants. These “operational” performance criteria may be, and often are, more restrictive than the structural criteria or tolerances.

Grade supported foundation or floor slab movements that approach one (1) inch may cause doors to stick, cracks in sheetrock or brittle floor covering, cracks in exterior finishes and other forms of cosmetic distress. Measures can and should be taken during the design and construction of the facility to help limit the extent and severity of these types of distress. However, these magnitudes of movement typically do not cause “structural distress”. If movements associated with grade supported slabs cannot be tolerated, the floor slab should be suspended above grade or driller pier foundations.

The soil moisture regime changes and resulting shrink/swell movements discussed above are based on typical seasonal moisture variations. However, extreme soil moisture variations could occur due to unusual drought severity, leaking utility lines, poor drainage, irrigation line breaks, perched groundwater infiltration, springs, vegetation (especially large trees) located adjacent to the building or previously underneath the building footprint, downspouts directing roof discharge under the foundation, etc. Therefore, because of these factors, the shrink/swell potential of expansive soils in the Central Texas area can often be difficult to quantify under these extreme circumstances.

Building Pad Preparation

Topsoil, vegetation, roots, and any soft soils in the construction areas should be stripped from the building sites and wasted. A portion of the existing soils (5.0 feet) within the proposed structures areas should be undercut and removed to allow for the placement of compacted select fill in order to meet a design PVR of 1-inch for the proposed structures. A representative of the Geotechnical Engineer should observe the depth of removal at the time of construction.

After stripping and excavating to the proposed subgrade level (5 feet below existing ground), the exposed subgrade should be proof-rolled with a heavily loaded tandem axle dump truck or similar rubber tired vehicle. Soils that are observed to rut or deflect excessively under the moving load should be removed and replaced with properly compacted select fill. The proof-rolling activities should be observed by a representative of the Geotechnical Engineer and should be performed during a period of dry weather.

After subgrade preparation and observation have been completed, select fill placement may begin to achieve the final pad elevations. Each layer of select fill should be placed in relatively uniform horizontal lifts with a maximum loose lift thickness of eight (8) inches. The thickness of each compacted lift should not exceed six (6) inches.

Subgrade preparation and select fill placement should extend at least 5 feet beyond the perimeter of the structure and should include any flatwork, covered walkways and other improvements adjacent to the structure. Flatwork adjacent to the edge of the structure foundation should extend at least 7 feet from the building or the edge of the building should be covered with asphalt or concrete pavement.

The use of a clay cap over poly sheeting (horizontal barrier) or impervious geosynthetic liner having a width of at least 7 feet or concrete (vertical barrier) is recommended in those landscaped areas not covered with paving or flatwork. Alternately, a vertical barrier having a depth of at least 5 feet below final grade is recommended in those areas not covered with asphalt or concrete pavement or flatwork.

Select Fill Recommendations

Select fill materials should be free of organic material and debris and should consist of low-expansive potential (inert) material such as silty or sandy lean clay (CL) or clayey sand (SC)

Select fill materials should have a liquid limit less than a Plasticity Index (PI) of between 7 and 20 and having at least 40% material passing the #200 sieve. The select fill materials should not possess stones with dimensions larger than 3 inches.

Pit-run fill materials are generally quarried and may receive minor amounts of processing prior to placement. Due to the relatively low amount of processing, pit run soil materials will often vary a significant amount with regard to gradation and index soil properties and therefore will require very frequent testing to verify that the properties remain consistent and within specification.

Expansive Soils Considerations

The above recommendations for the construction of the building pads require the removal of relatively impermeable clay soils and replacing them with volumetrically stable select fill materials

As water infiltrates the fill body, it can begin to pond over the subgrade at the bottom of the excavation. This condition can create a “bathtub” of trapped water that when sustained can affect the moisture variation zone and result in additional expansion of the underlying soils and cause distress to the foundation supported by the building pad. To reduce the risk of the occurrence of this scenario, the select fill should consist of a lean clay material or a clayey sand having sufficient fines to be relatively impermeable.

General Site Preparation Outside of Building Pad

Construction areas outside of the building pad areas for grade supported structures discussed above (including the soils beneath building areas utilizing a suspended floor slab) should be stripped of topsoil, vegetation, roots, loose or soft soils and any other deleterious materials. The stripped materials should be removed from the site and disposed of properly. Upon completion of stripping operations, the site may be either excavated or filled as necessary to achieve the desired site elevation. After site stripping and excavation, or prior to placement of any fill materials, the exposed subgrade should be proof-rolled with appropriate construction equipment weighing at least 20 tons.

Soils that are observed to rut or deflect excessively under the moving load should be removed and may be replaced with either properly compacted select fill materials or clean onsite soils.

Grade adjustments outside of any grade supported building pads can be made using select fill materials, onsite soils or imported general fill. All general fill placed on this site should be free of any deleterious materials and should not contain stones greater than three inches in maximum dimension. The fill materials should be placed on prepared surfaces in lifts not to exceed eight (8) inches loose measure, or six (6) inches compacted measure.

In areas where pavements are to be constructed, the subgrade should be prepared as recommended herein prior to placement of fill materials over the subgrade or construction of the pavement section.

Based on the pavement section recommendations provided later in this report, the final soil subgrade should be moisture conditioned as recommended in the section of this report entitled Pavement Material Specifications.

Compaction and Testing Requirements

The following table outlines compaction requirements in consideration of recommendations for the subject site. If water must be added, it should be uniformly applied and thoroughly mixed into the soil. Each lift of compacted select fill should be tested by a representative of the Geotechnical Engineer prior to placement of subsequent lifts. Care should be taken to apply consistent compactive effort throughout the construction areas.

Material Test Method for

Density Determination

Percent Compaction

Optimum Moisture Content

Testing Requirement

Subgrade soil (Structures and

Pavements) ASTM D 698 95% 0% to +4%

1 per 5,000 SF min. 3 tests

General Fill ASTM D 698 95% 0% to +4% 1 per 10,000 SF min. 3 tests

Select Fill ASTM D 698 95% -1 to +3% 1 per 5,000 SF;

min. 3 per lift

Slab-on-Grade Foundation Recommendations

A shallow, grid type beam and slab foundation is used to support relatively light structures upon expansive soils where soil conditions are relatively uniform, and where a calculated magnitude of movement can be tolerated. The intent of a stiffened slab-on-grade foundation is to allow the structure and foundation to move up and down freely with soil movements while providing a minimum sufficient stiffness to limit differential movements. Stiffened slab-on-grade foundations may be used on this project for the proposed structures.

Provided that the PVR movements of the magnitude as discussed earlier are reduced to acceptable levels and these movements will not impair the performance of the structures, stiffened grid type beam and slab or spread footing foundations may be utilized. Grade beams and spread beams bearing on a minimum of one foot of properly compacted select fill can be designed for an allowable soil bearing capacity of 3,000 psf. This value includes a design safety factor of approximately three.

Grade beams should be a minimum of 12 inches wide to prevent local shear failure and exterior beams should penetrate at least 18 inches below the final exterior grade. A vapor barrier should be placed beneath the floor slab in order to break the rise of capillary moisture. Isolated spread beams should bear at a minimum of 2 feet below final grade and should have a minimum dimension of two feet. These recommendations are intended for proper development of bearing capacity for continuous beam sections, to assure proper concrete cover is achieved between reinforcing steel and soil, and to reduce potential water migration beneath the foundation. These recommendations are not based on structural considerations. Therefore, the required grade beam widths and depths may be greater than recommended herein for structural considerations and should be properly evaluated and designed by the structural engineer.

Based on the "Design of Slab-On-Ground Foundations" published by the Wire Reinforcement Institute, Inc. (Aug., 1981), the following design criteria are provided for this site. The values consider sites/building pads prepared to reduce the PVR to approximately one inch or less, as recommended herein.

Proposed Buildings PVR of About 1 Inch

Climatic Rating (Cw) 16

Effective Plasticity Index (PI) 20

Soil/Climatic Rating Factor (1-C) 0.09

Post-Tensioning Institute (PTI) design parameters at this site are as follows. The values were derived considering the observed site soil conditions, the recommended building pad construction to reduce the PVR value to approximately one inch, and using the Third Edition of “Design of Post-Tensioned Slabs-on-Ground” and the Volflo 1.5 design software. If a design PVR different than one inch will be used, PSI should be contacted for the appropriate recommendations.

Proposed Auto/Stand Alone Building PVR of about 1 Inch

Edge Moisture Penetration Distance (Em) (center lift) (ft): 9.0

Estimated Ym values for Center Lift (shrink) Conditions (Inches) -0.95

Edge Moisture Penetration Distance (Em) (edge lift) (ft): 4.5

Estimated Ym values for Edge Lift (swell) Conditions (Inches) 1.23

Soil supported floor slabs are subject to vertical movements as discussed earlier in this report. This movement can cause distress to interior wall partitions supported by these slabs. This should be understood and addressed in the design phase of this project. Utilities that project through slab-on-grade floors should be designed with either some degree of flexibility or with sleeves in order to prevent damage to these lines should vertical movement occur.

Contraction, control or expansion joints should be designed and placed in various portions of the structure. Properly planned placement of these joints will assist in controlling the degree and location of material cracking which normally occurs due to material shrinkage, thermal affects, soil movements and other related structural conditions.

The foundation excavations should be observed by a representative of PSI prior to steel or concrete placement to assess that the foundation materials are capable of supporting the design loads and are consistent with the materials discussed in this report. This is especially important to identify the condition and acceptability of the fill material under the beams. Soft or loose soil zones encountered at the bottom of the footing or beam excavations should be removed to the level of competent soils as directed by the Geotechnical Engineer. Cavities formed as a result of excavation of soft or loose soil zones should be backfilled with compacted select fill.

After opening, footing and beam excavations should be observed and concrete placed as quickly as possible to avoid exposure to wetting and drying. Surface run-off water should be drained away from the excavations and not be allowed to pond. If footing excavations must be left open an extended period, they should be protected to reduce evaporation or entry of moisture.

Adjacent Sidewalks and Flatwork

Where movement sensitive flatwork will be constructed adjacent to the building, we recommend that the building pad area include these locations to reduce the PVR value in the flatwork areas and consequently reduce differential movements and associated reversed drainage, door jamming, tripping hazards, etc. Doweling the flatwork to the building foundation at common openings will further help to reduce the potential for differential movements and trip hazards. However, when doweling grade supported flatwork to more stable structures, movements of the flatwork can cause cracking in the flatwork itself. We recommend that if grade supported flatwork are dowelled to more stable foundations, the connections be designed such that they are flexible to rotate.

Proper drainage around grade supported sidewalks and flatwork is also very important to reduce potential movements. Elevating the sidewalks where possible and providing rapid, positive drainage away from them will reduce moisture variations within underlying expansive soils, and will therefore provide valuable benefit in reducing the full magnitude of potential movements from being realized.

Seismic Design Considerations

For the purposes of seismic design, based on the encountered site conditions and local geology, we interpreted the subsurface conditions to satisfy the Site Class D criteria for use at this site as defined by the 2015 International Building Code (IBC). The site class is based on the subsurface conditions encountered at our soil borings, the results of field and laboratory testing, our experience with similar projects in this area, and considering the site prepared as recommended herein. The table below provides recommended seismic parameters for the project based on the 2015 edition of the IBC.

The following parameters were developed using the United States Geological Survey geohazards webpage.

Recommended Design Seismic Parameters (Site Class D)

Seismic Parameter IBC 2012

0.2 sec (SS) 0.067 g

1.0 sec (S1) 0.035 g

Site Coefficient 0.2sec, Fa 1.6

Site Coefficient 1.0 sec, Fv 2.4

0.2 sec (SDS) 0.071 g

1.0 sec (SD1) 0.056 g

Pavement Recommendations

Pavement Design Discussion

It is understood that flexible and rigid pavements will be considered for this project. Therefore, pavement design recommendations for several levels of traffic loading were developed based on assumptions of potential trafficking, drive paths or patterns and anticipated soil support characteristics of pavement subgrades. We utilized the “AASHTO Guide for Design of Pavement Structures” published by the American Association of State Highway and Transportation Officials to evaluate the pavement thickness recommendations in this report. This method of design considers pavement performance, traffic, roadbed soil, pavement materials, environment, drainage and reliability. Each of these items is incorporated into the design methodology. PSI is available to provide laboratory testing and engineering evaluation to refine the site specific design parameters and sections, upon request.

Specific design traffic types and volumes for this project were not available to PSI at the issuance of this report. This traffic information is typically used to determine the number of 18-kip Equivalent Single Axle Loads (ESAL) that is applied to the pavement over its design life. Furthermore, our scope of services for this project did not include California Bearing Ratio (CBR) testing. In lieu of project specific design parameters, general trafficking and subgrade parameter considerations were used for this design. Based on this information, we have provided recommended pavement sections for “light duty”, “moderate duty” and “heavy duty” pavements constructed atop stable and properly prepared/compacted subgrades as previously recommended. Flexible pavement options with and without geogrid options are also provided for consideration. Details regarding the basis for this design are presented in the table following table.

Pavement Design Parameters (Rigid and Flexible)

Estimated CBR, percent 3

Reliability, percent 70

Initial Serviceability Index, Flexible Pavement 4.2

Initial Serviceability Index, Rigid Pavement 4.5

Terminal Serviceability Index 2.0

Standard Deviation, Flexible Pavement 0.45

Standard Deviation, Rigid Pavement 0.35

The presented recommended pavement sections are based on the field and laboratory test results for the project, local pavement design practice, design assumptions presented herein and our previous experience with similar projects. The project Civil Engineer should verify that the ESAL and other design values are appropriate for the expected traffic and design life of the project. PSI should be notified in writing if the assumptions or design parameters are incorrect or require modification.

Based on the design parameters listed above, we developed recommendations for “light duty,” “moderate duty” and “heavy duty” pavement sections. “Light duty” pavements are intended for general parking areas with passenger vehicles only and have an approximate capacity of at least 25,000 ESAL. “Moderate duty” pavements are intended for areas subject to channelized traffic and delivery areas and have an approximate ESAL capacity of at least 100,000. “Heavy duty” pavements are intended for areas subject to heavier vehicles with extensive turning, starting and stopping, such as pavement aprons associated with trash enclosures, and have an approximate ESAL capacity of at least 250,000. The project Civil Engineer should select the proper pavement section and verify that the ESAL values for the respective pavement areas are appropriate.

FLEXIBLE PAVEMENT SYSTEM

Recommended Thicknesses (Inches)

Light Duty Moderate Duty

Pavement Materials Option 1 Option 2 Option 1 Option 2

TxDOT Item 340, Type D Hot Mix Asphaltic Concrete

2½ 2 3 3

TxDOT Item 247, Type A, Grade 1-2 Flexible Base

6½ 8 8½ 6

Tensar TR-5 Triaxial Geogrid Base Course Reinforcement

-- -- -- Yes

Lime Treated Subgrade 8 8 8 8

RIGID PAVEMENT SYSTEM

Recommended Thicknesses (Inches)

Pavement Materials Light Duty Moderate Duty Heavy Duty

Reinforced Concrete 5 5.5 6.5

Lime Treated Subgrade 8 8 8

PSI recommends that proper perimeter drainage be provided and maintained to reduce the infiltration of surface water into the pavement section from surrounding unpaved areas. Landscape beds or islands in paved areas provide avenues for water to infiltrate the pavement section; and if used, should incorporate vertical moisture barriers to prevent the migration of water beneath the pavement surface. The infiltration of water into the pavement section typically results in the degradation of the section with time as vehicular traffic traverses the affected area.

Vertical curbs separating pavement and landscape areas should extend at least three inches below the bottom of the base materials to help reduce the potential for water infiltration into the pavement section. Surface and subdrains should be installed behind the curbs adjacent to ascending slopes to intercept and remove water from the pavement perimeter before the water infiltrates the pavement section. Furthermore, all concrete/asphalt interfaces should be sealed using a sealant that is compatible with both asphalt and concrete.

In areas of pavement that are subject to heavy wheel loads, substantial amounts of vehicle maneuvering, or high traffic volumes, we recommend that concrete pavements be used. The concrete pavements should be large enough to properly accommodate all vehicular traffic and loads.

In areas where waste bins or trash enclosures are located, the concrete pavement apron should be large enough to hold both the dumpster and the wheels of the garbage collection vehicle. Eight (8)-inch thick concrete pavement is recommended for Dumpster Pad areas and that area leading up to the Dumpster Pad. The concrete paving should extend beyond areas that undergo extensive turning, stopping, or maneuvering. The pavement design engineer should consider these and other similar situations when planning and designing pavement areas.

Pavement Material Specifications

The following guidelines have been prepared for use in consideration for selection and preparation of various materials that may be used to construct the pavement sections. Submittals should be made for each pavement material and should be reviewed by the Geotechnical Engineer and other appropriate members of the design team. The submittals should provide the test information necessary to verify full compliance of the materials with the recommended or specified material properties for the project. The proposed materials to be used in construction should be approved in writing from the governing authority prior to beginning construction. Conformance testing should be performed to document the actual field conditions at the time of construction, the observed construction practices and to assess that the materials used satisfy the project requirements.

Additionally, underground utility construction may impact the pavement performance. In areas of pavements, the trench backfill above bedding materials should be placed in maximum eight inch loose lifts and each lift should be compacted in accordance with the criteria for the type of material being placed.

Hot-Mix Asphaltic Courses - The asphaltic concrete should be plant mixed, hot laid, Type D (fine) surface course meeting the 2004 TxDOT Standard Specification Item 340, where applicable. Based upon the TxDOT Standard Specifications, the mix should be compacted to between 92 and 97 percent of the maximum theoretical density as determined by TEX-227-F.

Flexible Base Course - Flexible base materials should be placed in maximum six inch compacted lifts. The base materials should be compacted to at least 95 percent of the maximum dry density as determined by ASTM…