Attach 2) Drawings.pdf

PDF 3 MB Posted Jun 15, 2022

Attached to: B140 Foundation Repair
Solicitation number: FA303022R0006
Issued by: Department of the Air Force Air Education and Training Command

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Other files

File	Type	Posted
Attach 7) Questions and Answers.pdf	PDF	Jul 7, 2022
Solicitation - FA303022R0006.pdf	PDF	Jun 15, 2022
Attach 1) SOW B140 Foundation Repair.pdf	PDF	Jun 15, 2022
Attach 3) AF 66.pdf	PDF	Jun 15, 2022
Attach 6) Instructions to Offerors and Evaluation Criteria.pdf	PDF	Jun 15, 2022
Attach 4) Wage Determination TX20220282.pdf	PDF	Jun 15, 2022
Attach 5) BAL Template.docx	DOCX document	Jun 15, 2022

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Installation Layout

GOODFELLOW AIR FORCE BASE

Map Path: F:\Geo Base Data\Maps\0 Tem plates\BaseMapTem plate (current).m xd

Th is m ap is fo r reference o nly. Alth o ugh every effo rt h as been m ade to ensure the accuracy o f info rm atio n, erro rs and co nditio ns o riginating fro m physical so urces used to develo p the database m ay be reflected o n th is m ap. IGI&S “Geo Base” sh all no t be liable fo r any erro rs, o m issio ns, o r dam ages that result fro m inappro priate use o f th is do cum ent.

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BUILDING 140

1st Floor Plan

17 Civil Engineer Squadron

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1591846821C Callout Interior Condition:

Slab shows signs of settling. (Approx. 1" - 2" x Approx 170'+/- lf)

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¯*FLOOR PLAN SHOWN FOR APPROXIMATE REPRESENTATION PURPOSES ONLY

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August 2021 21-E-0298

SKG ENGINEERING, LLC

Geotechnical Report

Goodfellow Air Force Base

Building #140

Goodfellow Air Force Base, Texas

PREPARED FOR:

Mr. Zachary T. Stone Goodfellow Air Force Base 210 Scherz Boulevard Good Fellow Air Force Base, Texas 76908

8/10/2021 SKG Engineering, LLC

F-7608

1591846821C

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August 10, 2021 21-E-0298

Mr. Zachary T. Stone Goodfellow Air Force Base 210 Scherz Boulevard Goodfellow Air Force Base, Texas

Subject: Geotechnical Report, Goodfellow Air Force Base, Building #140, Goodfellow Air Force Base, Texas

Mr. Stone, In accordance with your authorization, SKG Engineering has completed its geotechnical investigation at the referenced site. The work was done in accordance with the proposal dated February 26, 2021. The data and results are included in the attached report.

If you have any questions or comments, or if we can be of any more service to you, please do not hesitate to contact us at (325) 655-1288.

Sincerely, SKG Engineering, LLC

Caleb Miller, E.I.T. Jason Clinton, P.E.

SKG Engineering, LLC

F-7608

Attachments - Geotechnical Report

CC: File

N:\Engineering\2021\21E0298 GAFB_Bldng 140\Geotech\Geotechnical Report.doc

Table of Contents

1.0 Introduction

1.1 Overview

2.0 Exploration

2.1 Soil Borings

2.2 Laboratory Tests

3.0 Subsurface Investigation

3.1 Site Geology

3.2 Subsurface Materials and Conditions

3.3 Subsurface Water

4.0 Site and Design Considerations

4.1 Basic Considerations

4.2 Subsurface Moisture

4.3 Shrink/Swell Considerations

4.4 Foundation System

4.4.1 Allowable Bearing Capacities

4.4.2 Potential Causes of Differential Settlement

4.4.3 Potential Foundation Repair Options

5.0 Material Specifications and Testing

5.1 Engineered Fill

5.2 Flexible Base Material

5.3 Testing

6.0 Limitations

Attachments

A – Field Conditions B – Sample Location Map C – Logs of Boreholes D – Laboratory Results E – Building Foundation Plans/Details (Provided to SKG)

Line

Building #140 August 2021 Goodfellow Air Force Base, Texas 21-E-0298

SKG Engineering, LLC 1 Geotechnical Report

1.0 Introduction

1.1 Overview

Reportedly, the referenced building has experienced noticeable shifting of the foundation since construction. Final elevations of the foundation system after completed construction are unknown.

Differential leveling in the areas of concern (provided to SKG Engineering by Goodfellow personnel) indicate the problem areas have settled up to approximately 1” below the floor level of the surrounding area. Structural plans and foundation details provided to SKG indicate the building is supported on a structural foundation system utilizing piers, with a floating slab which is not anchored to the exterior grade beam. A specific thickness for the slab was not shown on the plans provided. However, approximate scaling of the details shown indicate the plans called for an estimated slab thickness of 5.5” – 6.0”. The plans call for a vapor barrier beneath the concrete slab, followed by a 6” capillary water barrier and a minimum 24” of non-expansive fill. A copy of the plans/details given to SKG and which provide the stated information is included in Attachment E.

The purpose of this exploration was to determine subsurface materials and conditions and to establish the characteristics of these materials in order to define the existing parameters and discuss potential foundation repair options. Additionally, the existing foundation was also investigated at the site by means of foundation cores and samples of the construction base material. Refer to the foundation coring report, SKG project number 21-E-0298, dated August 10, 2021 for a further evaluation of the existing foundation system. A summary of field conditions is included in Attachment A.

2.0 Exploration

2.1 Soil Borings

The subsurface explorations were conducted on this site in July 2021. The boreholes were drilled to a maximum depth of 20', and the logs of these boreholes are included in this report. The drilling was performed with a truck mounted air rotary drill rig. The drilling activities were performed in accordance with accepted methods and procedures. The boreholes were conducted as near to the perimeter of the building as access would permit. A location map showing the approximate borehole locations is included in Attachment B.

Material samples were recovered at various depths for testing. The primary means of extracting subsurface soil samples was by the use of a 3" Shelby-tube and/or a 2" O.D. split barrel sampler. Split spoon sampling procedures were performed in accordance with ASTM D 1586 and Shelby tube samples were obtained in accordance with ASTM D 1587. The samples were extruded or removed in the field and placed in moisture tight bags and labeled. The samples were then transported to the laboratory for testing and visual evaluation by geotechnical personnel. The Unified Soil Classification System was utilized in accordance with ASTM D 2487 to verify field classifications. Refer to the logs of borings located in Attachment C for lithology, sample locations and quantities.

2.2 Laboratory Tests

Tests were performed to determine engineering characteristics of the subsurface materials encountered including, but not limited to, soil moisture content (ASTM D 2216), Atterberg Limits (ASTM D 4318) and sieve analysis. The test results can be found in Attachment D. Samples not tested in the laboratory will be retained for a maximum of 60 days and then discarded unless otherwise notified in writing prior to disposal of the samples.

SKG Engineering, LLC 2 Geotechnical Report

3.0 Subsurface Investigation

3.1 Site Geology

Based on the location of the site on geological maps, it is our opinion that the predominate soil is the Angelo-Urban Land Complex, (AuB). These particular soils are indicative of nearly level to gently sloping topography on smooth outwashed plains. These soils are well drained and have medium surface runoff. Shrink-swell potential and soil corrosivity to uncoated steel are moderate. Based on the location of the site and soil conditions we do not foresee any adverse issues related to elevated sulfate concentrations.

3.2 Subsurface Materials and Conditions

The specific subsurface stratum encountered in each borehole is described in the logs of boreholes included in Attachment C. The strata encountered at the boreholes conducted at the site can be divided into two major strata. The first stratum is a layer of lean clay that extends from a depth of 0' to 11'. The second soil stratum consists of fat clay extending from a depth of 11' to the depth of the boreholes.

The subsurface stratum varies from those stated above as follows:

B2 – Gravelly lean clay encountered from a depth of 2 feet to a depth of 5 feet;

For comparison to the specifications shown on the plans given to SKG, a detailed listing of the existing materials and conditions found beneath the slab is provided in the foundation coring report, SKG project number 21-E-0298, dated August 10, 2021.

3.3 Subsurface Water

There was no groundwater noted in any of the boreholes at the time of the investigation. The absence of groundwater noted does not express or imply a groundwater study was performed, which is beyond the scope of this report. It should be noted that groundwater levels are subject to change based on seasonal and climatic conditions.

4.0 Site and Design Considerations

4.1 Basic Considerations

The site is currently developed with the existing structure, subsurface utilities, flatwork, and landscaping.

Any foundation repairs performed in the area should take note of the existing developments during the design phase of the project in order to minimize damages.

Our understanding is the building is currently supported on a structural foundation system utilizing piers and that (at least in the areas of concern) the slab is floating and un-anchored to the perimeter grade beam. A complete foundation design and details concerning the bearing depth of the piers utilized was not provided.

Clay soils with moderate to high plasticity index (PI) values were encountered at the site at depths ranging from 0’ – 3’, and from 11’ to the depth of the borehole. These soils are a major contribution to the potential for vertical movement (PVR) at the site. PVR is further discussed in section 4.3 of this report. Movement generated by higher plasticity soils encountered at moderate to large depths are more difficult to accommodate with structures already present.

4.2 Subsurface Moisture

Water, in the form of a liquid, can rise upward through subsurface soils by capillary action, absorption or gravitational pull well above the water table. Water changes from a liquid to a vapor as it evaporates.

SKG Engineering, LLC 3 Geotechnical Report

Water vapor will move from areas of high vapor pressure to a lower vapor pressure through diffusion.

Diffusion is how water vapor distributes itself above the water table and occurs in both soils and concrete.

It is generally recognized that the relative humidity in the soils below a foundation will be close to 100%.

Such a high relative humidity is reached even when the moisture content in the material below the foundation is found to be low. Without a capillary break or vapor barrier below the foundation, a high relative humidity or water source below a foundation can contribute moisture to the concrete. This can cause soluble alkalis in the concrete to enter into solution thus raising the pH. Moisture induced pH levels in concrete can be on the range of 10 to 12 while normal cured levels can be on the range of 7 to 9.

The impact of subsurface moisture can be reduced by the use of a vapor barrier or capillary break. A vapor barrier below the foundation is recommended when floor coverings or adhesives are sensitive to moisture or alkaline conditions. A vapor barrier can be in the form of poly vinyl sheets and a capillary break can be a sand or granular base. Verification of the vapor emission limitations from the foundation is vital to the selection of the proper vapor barrier system.

4.3 Shrink/Swell Considerations

Shrink/swell movements of the in-situ soils with changes in the soil moisture content are anticipated to be medium at the site. The Potential Vertical Rise (PVR) was calculated to be on the order of 1-1/2" using the McDowell PVR Method. The PVR was approximated using the McDowell’s initial dry soil condition and a potential active zone to fifteen feet below grade. No information was provided as to whether soil modification was performed at this site during the original construction process. The intent of this section is to provide for a soil removal and replacement for the depths noted below which SKG Engineering would provide for new construction based on the encountered soil conditions.

The PVR can be reduced to be on the order of 1" by providing a 3' layer of engineered fill below the foundation. The PVR can be reduced to be on the order of ¾” by providing a 7' layer of engineered fill below the foundation. The PVR can be reduced to be on the order of ½" by providing a 12' layer of engineered fill below the foundation. When engineered fill is utilized to reduce the PVR, the continuous footings must bear at the same depth as the depth of the engineered fill or engineered fill should be placed below the grade beam to accomplish the required depth. Refer to the Engineered Fill section for placement and specifications.

The PVR and moreover foundation movement is effected by many factors that influence its magnitude and rate of change. Factors include: seasonal variations in the moisture content between the interior and perimeter of the foundation, topographic relief, vegetative cover, confining pressures, fluctuating and shallow water tables, and the composition of underlying soils. In-situ clays can expand with the introduction of moisture and shrink with decreases in moisture.

4.4 Foundation System

This section provides bearing capacities of the site soils and discusses potential causes of the differential settlement, and possible options for repair of the existing foundation. The bearing capacities provided are based on SKG’s evaluation of the soils encountered, and may vary from the values utilized when the foundation was designed. The bearing capacities are given for use in providing a general understanding of the site soil stiffness, for consideration of repair options.

4.4.1 Allowable Bearing Capacities

The allowable bearing pressure exerted by grade beams or spread footings on the in-situ soils from a depth of 1' to 2' is 2,000 psf and from a depth of 2' to 4' is 2,900 psf. The value of 125 pci for subgrade modulus may be used for design purposes. The value of 28 degrees may be utilized for the internal friction angle of the clayey soils for design purposes. The value of 0.35 for the ultimate lateral sliding

SKG Engineering, LLC 4 Geotechnical Report resistance coefficient may be utilized for design in regard to the foundation on an engineered fill. The allowable bearing pressure exerted by grade beams bearing into an engineered fill, placed in accordance with the specifications in the Site Preparation section of this report, is 3,500 psf.

Belled piers can be used for foundation support where column loads are less than 85 kips. The piers should bear a minimum of 16' up to 18’ below existing grade, bearing into the firm clay. The piers should be located below the active zone and founded on a firm, stable stratum. We recommend foregoing utilizing side shear resistance for the allowable bearing capacity of the piers between 0 and 10 feet of depth. The piers can be designed with an allowable side shear resistance of 450 psf for the portion of shaft extending from a depth of 10’ to the depth of the borehole, in addition to the allowable end bearing pressure stated below. An allowable side shear resistance of 350 psf for the portion of shaft extending from a depth of 10’ to the depth of the borehole may be utilized for uplift resistance. The allowable lateral bearing of the piers on the clayey soils may be taken as 150 psf/f. Field adjustments to some shaft depths may be required due to the variation in the site elevations and varied soils encountered. The allowable end bearing pressure exerted by the piers on the soils 16' to 18' below existing grade is 7,300 psf.

4.4.2 Potential Causes of Differential Settlement

The exact cause for the differential settlement of the slab could not be ascertained. Based on observation of the settlement and damage noted, it appears only the floating slab has settled, and that the piers have remained in place, creating a differential settlement of approximately 1”. Some potential contributors to the settlement may include the following:

Shrinkage of in-situ clay soils beneath the foundation due to changes in moisture content, or any of the other reasons discussed in Section 4.3.

Consolidation of the granular fill (specified as a 6” capillary water barrier and minimum 24” nonexpansive fill) placed beneath the vapor barrier.

It is noted in the coring report performed for the site that the capillary water barrier encountered appeared to be approximately 12” in depth, and comprised primarily of larger sized aggregate. It is possible that the gradation of material resulted in a capillary barrier layer which, though compacted, still retained substantial voids within the soil matrix. If this scenario occurred, it is also possible the capillary barrier has experienced consolidation over time, contributing to the differential settlement. Note that even if this is a contributing factor, SKG does not believe it likely for the entirety of the settlement noted to have occurred across such a small layer.

It is also noted in the coring report that the fill material used to bring the floor to the desired grade (specified as a minimum 24” layer) had moderate plasticity index (PI) values (on the range of 15 – 29).

SKG’s typical specifications for engineered fill material call for a PI value between 6 and 14. If a full 24” or greater depth of fill material was utilized with higher PI values, it is possible that over time the changes in moisture content within the fill layer could contribute to consolidation leading to differential settlement. Again, not knowing the full depth of the fill layer placed during construction makes it difficult to determine the amount of settlement which could be caused by this scenario. However, it is unlikely to be a sole contributor.

4.4.3 Potential Foundation Repair Options

Standard methods for repairing foundations include the following:

Steel Pressed Pilings Concrete Piers Helical Piers

SKG Engineering, LLC 5 Geotechnical Report

Slabjacking High-Density Polyurethane Foam Injection

Since it appears the structural piers have remained in place, with the differential settlement occurring only across the floating slab, we believe the existing condition of the slab/foundation may be improved by use of a high-density polyurethane foam injection. This is typically performed by drilling holes through the existing slab and injecting a high-density foam which fills in voids beneath the slab and raises the slab. It should be noted that if a portion of the settlement observed has been caused by a decrease in moisture conditions of either the in-situ or engineered fill soils, then it is possible that an increase in those moisture conditions could have a reverse effect, causing the slab to raise above the improved elevation.

Careful attention should be paid to the routing of stormwater drainage and runoff within the area to ensure water is not permitted to pond on the site.

5.0 Material Specifications and Testing

The material specifications and testing requirements in this section are provided as a comparative reference, and to demonstrate SKG’s typical specifications in these areas.

5.1 Engineered Fill

An approved select fill shall be used to bring the foundation system to grade. It shall be a non-granular, cohesive soil, free of deleterious material, have a liquid limit of less than 40, and a plasticity index between 6 and 14. The select fill shall meet the following percent retained on sieve requirements: 2-1/2":

0-5%, No. 4: 40-80%, and No. 40: 50-85% or obtain approval from the geotechnical engineer. The fill should be installed in maximum eight-inch loose lifts and compacted to at least 95% of the Standard Proctor Density within 3% points of the optimum moisture content. Base consisting of TxDOT Type A, Grade 2 limestone will be accepted as engineered fill. Blended materials utilized for engineered fill will have to meet the specifications herein and be approved by the geotechnical engineer. If a blended material is approved, the contractor shall blend the material and have one stockpile for the entire project.

Continuous blending of material throughout the duration of the project is not acceptable.

5.2 Flexible Base Material

Provide compacted base consisting of Type A, Grade 2, limestone material below the foundation.

Compact to 96% of the Standard Proctor Density within 2% points of the optimum moisture content.

Material shall be placed in lifts not to exceed 8". Alternative flexible base materials provided by a local supplier which do not meet theses specifications shall be approved by the Engineer of record.

5.3 Testing

Test results of the engineered fill shall be submitted to the engineer of record for approval prior to incorporating into the work. Arrange for a testing agency to verify flexible base, engineered fill, and subgrade compaction and moisture content. To confirm the compaction of the subgrade, engineered fill, and base we recommend the more stringent of three density tests for each lift placed or one density test for every 2,000 square feet of foundation area for each lift placed. The Standard Proctor Density shall be determined in accordance with ASTM D698.

6.0 Limitations

The recommendations presented in this report are based upon the information obtained from the borings performed at the site and from other information discussed in this report. This report is based upon the findings from the borings made and may not identify all subsurface variations which exist across the site.

The nature and extent of such variations may not become evident until construction. If significant variations appear, contact SKG Engineering to further access the design criteria and the recommendations contained within this report.

SKG Engineering, LLC 6 Geotechnical Report

The scope of services for this project does not include either specifically or by implication any environmental assessment of the site or identification of contaminated or hazardous materials or conditions. If the owner is concerned about the potential for such conditions, the appropriate investigations should be performed.

No warranties, either expressed or implied, are intended or made. In the event that changes in the nature, design, or location of the project as outlined in this report are made, the recommendations contained in this report shall not be considered valid unless SKG Engineering reviews the changes and either verifies or modifies the conclusions of this report in writing.

Attachment A

Field Conditions

Summary of Field Conditions

The following field conditions were observed during the field exploration activities.

1. The site is developed with the existing structure, subsurface utilities, flatwork, and landscaping.

The accessibility of some types of equipment should be verified in some of the areas of the site where heavy development is present, and due diligence should be performed to avoid disturbing subsurface utilities.

2. The surface soil conditions on the site are generally clay that is considered a soft soil material. The soil conditions will probably prove to hinder mobilization of some types of construction equipment during rain events that saturate the soils.

3. Groundwater was not present at the time of drilling activities in any of the boreholes.

4. No rock was encountered in any of the boreholes conducted at the site.

Attachment B

Borehole Location Map

Attachment C

Logs of Boreholes

SAMPLER TYPE

UNIFIED SOIL CLASSIFICATION SYSTEM u u\GRAPHIC

SYMBOL

LETTER

SYMBOLMAJOR DIVISION TYPICAL DESCRIPTIONS

°o «°9 0 O

CLEAN

GRAVELS

WELL GRADED GRAVELS, GRAVEL-SAND MIXTURES,

LITTLE OR NO FINES.GWGRAVEL AND

GRAVELLY

SOILS

TXDOT

SAMPLE CONE

NO SHELBY

TUBE RECOVERY

NO ROCK

CORE

SPLIT

SPOON

WATER TABLE AT

TIME OF DRILLING

BAG

SAMPLE

(LITTLE OR NO

FINES)

POORLY GRADED GRAVELS OR GRAVEL-SAND

MIXTURES, LITTLE OR NO FINES. W WATER LEVEL AT

= END OF DRILLING

GP VCOURSE

GRAINED

SOILS

GRAVELS

WITH FINES

(APPRECIABLE

AMOUNT OF

FINES)

MORE THAN 50%

OF COARSE

FRACTION

RETAINED ON

NO. 4 SIEVE

DESCRIPTIONSILTY GRAVELS, GRAVEL-SAND-SILT MIXTURES. SOIL TERMSGM

CONTAINS CRACKS OR FAILURE PLANES RESULTING IN ROUGH

CUBES OF MATERIAL.BLOCKY

GC CLAYEY GRAVELS, GRAVEL-SAND-SILT MIXTURES.

CONTAINS APPRECIABLE QUANTITIES OF CALCIUM CARBONATE.CALCAREOUS

CONTAINS SHRINKAGE CRACKS, WHICH ARE FREQUENTLY FILLED

WITH FINE SAND OR SILT. THE FISSURES ARE USUALLY NEAR

VERTICAL IN ORIENTATION.

WELL GRADED SANDS, GRAVELLY SANDS, LITTLE OR

NO FINES.SILTS sw FISSUREDCLEAN SAND

AND

tig(LITTLE OR NO

FINES)

POORLY GRADED SANDS OR GRAVELLY SANDS, LITTLE

OR NO FINES.CLAYS INTERBEDDED COMPOSED OF ALTERNATING LAYERS OF DIFFERENT SOIL TYPES.SPMORE THAN 50%

OF MATERIAL IS

LARGER THAN NO.

200 SIEVE SIZE.

COMPOSED OF THIN LAYERS OF VARYING COLOR AND TEXTURE.LAMINATEDSANDS WITH

FINES

(APPRECIABLE

AMOUNT OF

FINES)

MORE THAN 50%

OF COARSE

FRACTION

PASSING

NO. 4 SIEVE

^ SECONDARY INCLUSIONS THAT APPEAR AS SMALL LUMPS ABOUT

0.1 TO 0.3 INCH IN DIAMETER.

r SM SILTY SANDS, SAND-SILT MIXTURES.m NODULES mfa INCLUSION OF DIFFERENT MATERIAL LESS THAN % INCH THICK

EXTENDING THROUGH THE SAMPLE.PARTINGSSC CLAYEY SANDS, SAND-CLAY MIXTURES.

yy INCLUSION OF DIFFERENT MATERIAL THAT IS SMALLER THAN THE

DIAMETER OF THE SAMPLE.POCKETSINORGANIC SILTS AND VERY FINE SANDS, FINE

SANDS, ROCK FLOUR, SILTY OR CLAYEY FINE SANDS

OR CLAYEY SILTS AND WITH SLIGHT PLASTICITY.ML

INCLUSION OF DIFFERENT MATERIAL BETWEEN ^ AND 3 INCHES

THICK, AND EXTENDS THROUGH THE SAMPLE.SEAMSSILTS INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY, GRAVELLY CLAYS, SANDY CLAYS, SILTY CLAYS, LEAN CLAYS.

LIQUID LIMIT

LESS THAN 50.

FINE

GRAINED

SOILS

CL HAS INCLINED PLANES OF WEAKNESS THAT ARE SLICK AND

GLOSSY IN APPEARANCE. SLICKENSIDES ARE COMMONLY

THOUGHT TO BE RANDOMLY ORIENTED.

AND

SLICKENSIDEDXCLAYS ORGANIC SILTS AND ORGANIC SILTY CLAYS OF LOW

PLASTICITY.OL STREAKS OR

STAINS

STAINS OF LIMITED EXTENT THAT APPEAR AS SHORT STRIPES,

SPOTS OR BLOTCHES.

INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS

FINE SAND OR SILTY SOILS.MH ROCK TERMSSILTS LIQUID LIMIT

GREATER THAN 50.

MORE THAN 50%

OF MATERIAL IS

SMALLER THAN NO

200 SIEVE SIZE.

A SURFACE PARALLEL TO THE SURFACE OF DEPOSITION,

GENERALLY MARKED BY CHANGES IN COLOR OR GRAIN SIZE.AND INORGANIC CLAYS OF HIGH PLASTICITY, FAT CLAYS.CH BEDDING PLANE2CLAYS

A NATURAL BREAK IN ROCK ALONG WHICH NO DISPLACEMENT

HAS OCCURED.ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY,

ORGANIC SILTS. FRACTUREOH

A NATURAL BREAK ALONG WHICH NO DISPLACEMENT HAS

OCCURED, WHICH GENERALLY INTERSECTS PRIMARY SURFACES.JOINT

PEAT, HUMUS, SWAMP SOILS WITH HIGH ORGANIC

CONTENTS.HIGHLY ORGANIC SOILS PT THE RATIO OF TOTAL LENGTH OF RECOVERY TO THE TOTAL

LENGTH OF CORE RUN, EXPRESSED AS A PERCENTAGE.% RECOVERY

ROD - ROCK

QUALITY

DESIGNATION

CONSISTENCY OF COHESIVE SOILSMOISTURE CONTENT THE RATIO OF TOTAL RECOVERED LENGTH OF FRAGMENTS

LONGER THAN 4 INCHES TO THE TOTAL RUN LENGTH,

EXPRESSED AS A PERCENTAGE.POCKET PENETROMETER

READING IN TONS/FT2

N-VALUE

(BLOWS/FOOT)

ABSENCE OF MOISTURE, DUSTY,

DRY TO THE TOUCH. CONSISTENCYDRY

THE PROCESS BY WHICH ROCK IS BROKEN DOWN AND

DECOMPOSED.

WEATHERINGVERY SOFT 0 TO 0.25 <2SOME PERCEPTIBLE MOISTURE;

BELOW OPTIMUM.DAMP SOFT 0.25 TO 0.5 2 TO 4

FIRM 0.5 TO 1.0 4 TO 8NO VISIBLE WATER; NEAR OPTIMUM

MOISTURE CONTENT.MOIST KEY

TO SYMBOLS AND TERMS

STIFF 1.0 TO 2.0 8 TO 15

VERY STIFF 2.0 TO 4.0 15 TO 30VISIBLE FREE WATER, USUALLY

SOIL IS BELOW WATER TABLE.WET >4.0 OR 4.5+ >30HARD

RELATIVE DENSITY-GRANULAR SOILSSAND GRAVELCLAY N-VALUE (BLOWS/FOOT)SILT CONSISTENCYCOBBLES BOULDERS

FINE MEDIUM COARSE FINE COARSE VERY LOOSE 0 TO 4

0.005mm No.200 No.40 No.10 No.4 %” 3”

U.S. STANDARD SIEVE SIZE

REFERENCE: THE UNIFIED SOIL CLASSIFICATION SYSTEM, CORPS OF ENGINEERS, U.S. ARMY

TECHNICAL MEMORANDUM NO. 3-357, VOL. 1 MARCH, 1953 (REVISED APRIL, 1960)

12” LOOSE 5 TO 10

MEDIUM DENSE 11 TO 30

DENSE 31 TO 50 ENGINEERING

VERY DENSE >50 OR 50+

COARSE

lean CLAY (CL); brown, with sand sandy lean CLAY (CL); brown fat CLAY (CH); tan

Boring completed at a depth of 20'. Groundwater was not present at the time of drilling activities.

4/6/11 9.4 24

10/9/9

6/9/12 9.8 16

GRAB

11/13/16

11/33/31 11.1 29

17/40/42

G W

T n o t e n c o u n te re d

SKG Engineering, LLC

S u p e rL o g

C iv il T e c h

S o ft w a re

S A w w

.c iv il te c h

.c o m

F il e

E n g in e e ri n g

\2 \2

A F

B B ld n g

\G e o te c h

\F in a l

B o re h o le l o g s .l g

D a te

Goodfellow Air Force Base - Bldg. #140 San Angelo, Texas

21-E-0298

B-1

Boring Location: Refer to the borehole location map

Date Started: July 9, 2021

Drilling Method: Air rotary

Hammer Weight: 140 lbs

Sampler: Shelby tube/2" split barrel sampler

Date Finished: July 9, 2021

Drop: 30 inches

Surface Elevation:

Depth (feet)

Lith-ology Material Description

Samples

N u m b e r

T y p e

SPT

Laboratory

W% PI

Project:

Plate A-

Pent.

(tsf) lean CLAY (CL); brown gravelly lean CLAY (CL); brown lean CLAY (CL); light brown fat CLAY (CH); tan

Boring completed at a depth of 20'. Groundwater was not present at the time of drilling activities.

2.5

9.3 23 3.0

4.5+

GRAB

5/7/7 11.7 16

16/27/38

18/37/44 10.2 35

G W

T n o t e n c o u n te re d

SKG Engineering, LLC

S u p e rL o g

C iv il T e c h

S o ft w a re

U w

.c iv il te c h

.c e

E n g in e e ri n g

\2 \2

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B B ld n g

\G e o te c h

\F in a l

B o re h o le l o g s .l te

Goodfellow Air Force Base - Bldg. #140 San Angelo, Texas

21-E-0298

B-2

Boring Location: Refer to the borehole location map

Date Started: July 9, 2021

Drilling Method: Air rotary

Hammer Weight: 140 lbs

Sampler: Shelby tube/2" split barrel sampler

Date Finished: July 9, 2021

Drop: 30 inches

Surface Elevation:

Depth (feet)

Lith-ology Material Description

Samples

N u m b e r

T y p e

SPT

Laboratory

W% PI

Project:

Plate A-

Pent.

(tsf) lean CLAY (CL); brown fat CLAY (CH); gray

Boring completed at a depth of 20'. Groundwater was not present at the time of drilling activities.

3/5/8 15.4 29

7/8/11

8/11/14

GRAB 9.0 18

7/6/8

13/27/30 15.9 57

50-3"

G W

T n o t e n c o u n te re d

SKG Engineering, LLC

S u p e rL o g

C iv il T e c h

S o ft w a re

U w

.c iv il te c h

.c e

E n g in e e ri n g

\2 \2

A F

B B ld n g

\G e o te c h

\F in a l

B o re h o le l o g s .l te

Goodfellow Air Force Base - Bldg. #140 San Angelo, Texas

21-E-0298

B-3

Boring Location: Refer to the borehole location map

Date Started: July 9, 2021

Drilling Method: Air rotary

Hammer Weight: 140 lbs

Sampler: Shelby tube/2" split barrel sampler

Date Finished: July 9, 2021

Drop: 30 inches

Surface Elevation:

Depth (feet)

Lith-ology Material Description

Samples

N u m b e r

T y p e

SPT

Laboratory

W% PI

Project:

Plate A-

Pent.

(tsf)

Attachment D

Laboratory Results

CLIENT:

PROJECT:

PROJECT #:

DATE:

0572 B1(2) 0' 1.5' 19 43 24 9.4 95.9 88.6 77.9 0573 B1(2) 3.5' 5' 14 30 16 9.8 93.9 73.0 62.1 0574 B1(2) 13.5' 15' 18 46 29 11.1 99.7 95.7 88.5 0575 B2 1.5' 3' 19 42 23 9.3 75.7 74.0 67.4 0576 B2 8.5' 10' 19 36 16 11.7 99.5 97.0 91.0 0577 B2 18.5' 20' 18 54 35 10.2 99.6 98.4 86.3 0578 B3 0' 1.5' 19 48 29 15.4 99.5 96.8 89.4 0579 B3 6' 7.5' 14 32 18 9.0 99.8 97.8 93.5 0580 B3 13.5' 15' 21 79 57 15.9 97.0 84.5 80.5

81.8

Stephanie Cheatheam Lab/CMT Manager

Pass # 200

Sieve (%)*

Average PL Average LL Average PI

Moisture

Pass # 4

Sieve (%)*

ANALYSIS RESULTS

Lab No. Description Plastic

Limit (%) *

Liquid

Limit (%)*

Plasticity

Index *

Building 140, GAFB 21-E-0298 7/15/2021

Zachary T. Stone, GS-09, DAF

Average % Clay

Pass # 40

Sieve (%)*

August 10, 2021 21-E-0298

Mr. Zachary T. Stone Goodfellow Air Force Base 210 Scherz Boulevard Goodfellow Air Force Base, Texas 76908

Subject: Foundation Coring Building 140 Goodfellow Air Force Base, Texas

Mr. Stone, Upon your request, SKG Engineering has performed coring of the foundation and sampling of the subsurface soils at the aforementioned location.

Purpose The purpose of the coring was to determine the thickness of the slab that is present and break the concrete cores to determine the compressive strength of the concrete. The purpose for sampling the subsurface soils was to perform testing for gradation and Atterberg limits to better define some of the engineering properties of the materials used for construction. This report is intended to provide these parameters and to be used in conjunction with the geotechnical report performed by SKG Engineering for this location. In an effort to make these determinations, the following was performed: two 6” diameter cores and two 4” diameter cores of the concrete slab were recovered with an electric, water-cooled core drill; the slab thickness, base thickness, if any were determined by visual observation and field measurements. Samples of the subsurface base material were collected using a hand auger to a depth of refusal for laboratory analyses. The slab survey provided to SKG by Goodfellow personnel was used to evaluate relative elevation differences.

Slab Properties A vapor barrier was present beneath the slab at all of the cored locations. The concrete core labeled C1 was 3.625 inches in diameter, with a length of approximately 6.25 inches and a tested compressive strength of 4,689 psi. The concrete core labeled C2 is 5.75 inches in diameter, with a length of approximately 6.5 inches and a tested compressive strength of 4,878 psi. The concrete core labeled C3 is 5.75 inches in diameter, with a length of approximately 6.5 inches and a tested compressive strength of 6,058 psi. The concrete core labeled C4 is 3.625 inches in diameter, with a length of approximately 6.5 inches and a tested compressive strength of 5,813 psi. Refer to Attachment A for core locations and Attachment B for compressive strength results.

Foundation Coring GAFB, Building #140

Soil Properties In general, a gravel capillary water barrier was encountered immediately beneath the vapor barrier, and appeared to be on the range of 10” – 12” thick. Soil samples were recovered with the hand auger to the refusal depths noted herein. Augering the base and soils beneath the slab was attempted with hand augers due to the restricting ceiling height for machinery inside the building. At C1 location, we augered to 18” below the slab until refusal and encountered tan gravel with clay fines. At C2 location, we augered to to 18” below the slab until refusal and encountered silty clayey gravel with sand. At C3 location, we augered to 18” below the slab until refusal and encountered silty clayey gravel with sand. At C4 location we augered to 22” below the slab until refusal, and encountered clayey sand with gravel. Refer to Attachment C for laboratory results of the soil samples Atterberg limits.

Gradation testing was performed on the soil and base samples collected from beneath the slab. It should be noted that samples of the base material were collected by hand through the core boring, and may not be fully representative across the gradation scale of the material used during construction. Refer to Attachment D for laboratory results of the soil samples gradation.

Conclusions Concrete Slab:

The slab parameters are provided herein for the project engineer’s use. We recommend to evaluate the slab as a 6.25” thick slab with a compressive strength of 4,500 psi. It could not be ascertained what reinforcement was present in the slab. Additional, invasive inspection would have to be done by the contractor to determine the reinforcement size and spacing.

Base Material & Subsurface Soils:

The samples collected were evaluated against the standard industry (within Texas) specifications for flexible base material, which can be found in TXDOT Item 247. A copy of the flexible base specifications is included in Attachment E. Laboratory testing of the samples recovered indicates the base material utilized does not meet TXDOT item specifications in either the gradation or plasticity index requirements.

This report serves to provide information regarding the existing conditions and associated measurements of the site elements. No design or recommendations are given or implied herein.

Also, we performed a geotechnical investigation of the site soils adjacent to this building. Refer to the geotechnical report, SKG project number 21-E-0298, dated August 10, 2021 for a further evaluation of site soil conditions.

Foundation Coring GAFB, Building #140

If you have any questions or comments, or if we can be of any further service to you, please do not hesitate to contact us at (325) 655-1288.

Sincerely, SKG Engineering

Jason Clinton, P.E.

SKG Engineering Firm #F-7608

CC: File

Attachments: Attachment A, Core Hole Location Map (1 page), Attachment B, Concrete Compressive Strength Results (1 page) Attachment C, Soil Results – Atterberg Limits (1 page) Attachment D, Soil Results – Gradation Testing (4 pages) Attachment E, TXDOT Item 247, Specifications for Flexible Base (2 pages)

N:\Engineering\2021\21E0298 GAFB_Bldng 140\Coring\Coring Report.doc

Client: 21E0298

Address:

Project: 7/6/2021

C1 3.625 x 5.4 0.96 50410 10.32 4689

C2 5.75 x 6.3 0.87 145500 25.95 4878

C3 5.75 x 6.5 0.87 180700 25.95 6058

C4 3.625 x 5.3 0.96 62490 10.32 5813

Report Date:

Note: This report is for the exclusive use of the client addressed.

This report may not be reproduced except in its entirety, without the written consent of SKG. Results apply only to above tests.

Sample Data

Core

Building 140, GAFB

CONCRETE CORE COMPRESSION TEST REPORT

GAFB - Zachary T. Stone

Correction Factor

Area

(sq. in.)

Strength (psi)

Project No.:

210 Scherz Blvd.

GAFB, Texas 769089

Max. Load (lbs.)

Size (in.)

CLIENT:

PROJECT:

PROJECT #:

DATE:

0540 C1 12'' 18'' 15 44 29 3.8 16.9 12.8 10.5 0541 C2 10'' 18'' 19 34 15 5.4 29.4 22.2 17.5 0542 C3 12'' 18'' 16 40 24 10.6 41.0 31.2 25.2

0543 C4 12'' 22'' 15 35 20 20.8 55.9 41.4 31.7

21.2

Stephanie Cheatheam Lab/CMT Manager

Pass # 200

Sieve (%)*

Moisture

Pass # 4

Sieve (%)*

Average % Clay

Pass # 40

Sieve (%)* Lab No. Description

Plastic

Limit (%) *

ANALYSIS RESULTS

Average PL Average LL Average PI

Zachary T. Stone, GS-09, DAF Building 140, GAFB

21-E-0298 7/2/2021

Liquid

Limit (%)*

Plasticity

Index *

Client / Project #: Lab #:

Sample Description: Tech:

Sample Mass (g):

Sieve Size Mass Retained

(g) % Retained

% Cumulative

(Previous Cumulative %

+ Current % Retained)

2 1/2" 0.0 0.0 0.0

2" 0.0 0.0 0.0

1 3/4" 0.0 0.0 0.0

1 1/2" 0.0 0.0 0.0

7/8" 116.0 11.4 11.4

3/4" 202.0 19.8 31.1

5/8" # 231.0 8 22.6 53.7

1/2" # 246.0 # 24.1 77.8

3/8" # 146.0 # 14.3 92.1

1/4" # 73.0 # 7.1 99.3

#4 # 1.1 # 0.1 99.4

#16 # 1.0 # 0.1 99.5

Remaining Soils # 5.0 # 0.5 100.0

21-0544

B. Cazares

1021.6

GAFB / 21E0298

Building 140

C1 0" - 12"

Sample Mass (g):

Sieve Size Mass Retained

(g) % Retained

% Cumulative

(Previous Cumulative %

+ Current % Retained)

2 1/2" 0.0 0.0 0.0

2" 0.0 0.0 0.0

1 3/4" 0.0 0.0 0.0

1 1/2" 0.0 0.0 0.0

7/8" 231.6 23.8 23.8

3/4" 196.4 20.2 44.0

5/8" # 163.7 6 16.8 60.8

1/2" # 176.2 # 18.1 78.9

3/8" # 129.6 # 13.3 92.2

1/4" # 70.6 # 7.2 99.4

#4 # 1.1 # 0.1 99.5

#16 # 1.4 # 0.1 99.7

Remaining Soils # 3.2 # 0.3 100.0

21-0545

B. Cazares

973.8

GAFB / 21E0298

C2 0" - 12"

Sample Mass (g):

Sieve Size Mass Retained

(g) % Retained

% Cumulative

(Previous Cumulative %

+ Current % Retained)

2 1/2" 0.0 0.0 0.0

2" 0.0 0.0 0.0

1 3/4" 0.0 0.0 0.0

1 1/2" 0.0 0.0 0.0

7/8" 140.9 21.1 21.1

3/4" 43.8 6.6 27.6

5/8" # 101.0 5 15.1 42.7

1/2" # 130.9 # 19.6 62.3

3/8" # 125.4 # 18.8 81.1

1/4" # 119.9 # 17.9 99.0

#4 # 2.7 # 0.4 99.4

#16 # 3.4 # 0.5 99.9

Remaining Soils # 0.8 # 0.1 100.0

21-0546

B. Cazares

668.5

GAFB / 21E0298

C3 0" - 12"

Sample Mass (g):

Sieve Size Mass Retained

(g) % Retained

% Cumulative

(Previous Cumulative %

+ Current % Retained)

2 1/2" 0.0 0.0 0.0

2" 0.0 0.0 0.0

1 3/4" 0.0 0.0 0.0

1 1/2" 0.0 0.0 0.0

7/8" 308.7 38.3 38.3

3/4" 107.2 13.3 51.5

5/8" # 152.5 4 18.9 70.5

1/2" # 89.8 # 11.1 81.6

3/8" # 110.1 # 13.6 95.2

1/4" # 36.8 # 4.6 99.8

#4 # 0.4 # 0.0 99.8

#16 # 0.1 # 0.0 99.9

Remaining Soils # 1.2 1 0.1 100.0

21-0547

B. Cazares

806.8

GAFB / 21E0298

C4 0" - 12"

Item 247

Flexible Base

1. DESCRIPTION

Construct a foundation course composed of flexible base.

2. MATERIALS

Furnish uncontaminated materials of uniform quality that meet the requirements of the plans and specifications. Notify the Engineer of the proposed material sources and of changes to material sources. The Engineer may sample and test project materials at any time before compaction throughout the duration of the project to assure specification compliance. Use Tex-100-E material definitions.

2.1. Aggregate. Furnish aggregate of the type and grade shown on the plans and meeting the requirements of Table 1. Each source must meet Table 1 requirements for liquid limit, plasticity index, and wet ball mill for the grade specified. Do not use additives, such as but not limited to lime, cement, or fly ash to modify aggregates to meet the requirements of Table 1 unless shown on the plans.

Table 1 Material Requirements

2.1.1. Material Tolerances. The Engineer may accept material if no more than 1 of the 5 most recent gradation tests has an individual sieve outside the specified limits of the gradation.

Property Test Method Grade 1–2 Grade 3 Grade 42 Grade 5

Sampling Tex-400-A

Master gradation sieve size (cumulative % retained)

Tex-110-E

2-1/2" 0 0

As shown on the plans

1-3/4" 0–10 0–10 0–5

7/8" 10–35 – 10–35

3/8" 30–65 – 35–65

#4 45–75 45–75 45–75

#40 65–90 50–85 70–90

Liquid Limit, % Max Tex-104-E 40 40 As shown on the plans

Plasticity Index, Max1 Tex-106-E

10 12 As shown on the plans

Plasticity index, Min1 As shown on the plans As shown on the plans As shown on the plans As shown on the plans

Wet ball mill, % Max

Tex-116-E

40 – As shown on the plans

Wet ball mill, % Max increase passing the #40 sieve

20 – As shown on the plans

Min compressive strength, psi

Tex-117-E

As shown on the plans lateral pressure 0 psi 35 – – lateral pressure 3 psi – – 90 lateral pressure 15 psi 175 – 175

1. Determine plastic index in accordance with Tex-107-E (linear shrinkage) when liquid limit is unattainable as defined in Tex-104-E.

2. Grade 4 may be further designated as Grade 4A, Grade 4B, etc.

When target grading is required by the plans, no single failing test may exceed the master grading by more than 5 percentage points on sieves No. 4 and larger or 3 percentage points on sieves smaller than No. 4.

The Engineer may accept material if no more than 1 of the 5 most recent plasticity index tests is outside the specified limit. No single failing test may exceed the allowable limit by more than 2 points.

2.1.2. Material Types. Do not use fillers or binders unless approved. Furnish the type specified on the plans in accordance with the following:

2.1.2.1. Type A. Crushed stone produced and graded from oversize quarried aggregate that originates from a single, naturally occurring source. Do not use gravel or multiple sources.

2.1.2.2. Type B. Crushed or uncrushed gravel. Blending of 2 or more sources is allowed.

2.1.2.3. Type C. Crushed gravel with a minimum of 60% of the particles retained on a No. 4 sieve with 2 or more crushed faces as determined by Tex-460-A, Part I. Blending of 2 or more sources is allowed.

2.1.2.4. Type D. Type A material or crushed concrete. Crushed concrete containing gravel will be considered Type D material. Crushed concrete must meet the requirements in Section 247.2.1.3.2., “Recycled Material (Including Crushed Concrete) Requirements,” and be managed in a way to provide for uniform quality. The Engineer may require separate dedicated stockpiles in order to verify compliance.

2.1.2.5. Type E. Caliche, iron ore or as otherwise shown on the plans.

2.1.3. Recycled Material. Reclaimed asphalt pavement (RAP) and other recycled materials may be used when shown on the plans. Request approval to blend 2 or more sources of recycled materials.

2.1.3.1. Limits on Percentage. Do not exceed 20% RAP by weight, when RAP is allowed, unless otherwise shown on the plans. The percentage limitations for other recycled materials will be as shown on the plans.

2.1.3.2. Recycled Material (Including Crushed Concrete) Requirements.

2.1.3.2.1. Contractor-Furnished Recycled Materials. Provide recycled materials, other than RAP, that have a maximum sulfate content of 3,000 ppm when tested in accordance with Tex-145-E. When the Contractor furnishes the recycled materials, including crushed concrete, the final product will be subject to the requirements of Table 1 for the grade specified. Certify compliance with DMS-11000, “Evaluating and Using Nonhazardous Recyclable Materials Guidelines,” for Contractor furnished recycled materials. In addition, recycled materials must be free from reinforcing steel and other objectionable material and have at most 1.5% deleterious material when tested in accordance with Tex-413-A. For RAP, do not exceed a maximum percent loss from decantation of 5.0% when tested in accordance with Tex-406-A. Test RAP without removing the asphalt.

2.1.3.2.2. Department-Furnished Required Recycled Materials. When the Department furnishes and requires the use of recycled materials, unless otherwise shown on the plans:

Department-required recycled material will not be subject to the requirements in Table 1, Contractor-furnished materials are subject to the requirements in Table 1 and this Item, the final product, blended, will be subject to the requirements in Table 1, and for final product, unblended (100% Department-furnished required recycled material), the liquid limit, plasticity index, wet ball mill, and compressive strength is waived.

Crush Department-furnished RAP so that 100% passes the 2 in. sieve. The Contractor is responsible for uniformly blending to meet the percentage required.

B140 - Work Task _ 4825377 3C - 140 - WT - STRUCTURE SHOP - AEROBIC RO.pdf

B140 - Site Dwg.pdf

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File details come from the government source that posted it. Updated Jun 15, 2022.