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GEOTECHNICAL ENGINEERING REPORT

Proposed Fire Station 54 Foster Road

San Antonio, Texas

PSI Project No. 0312-1609

PREPARED FOR:

City of San Antonio P.O. Box No. 839966

San Antonio, Texas 78283

March 1, 2018

BY:

PROFESSIONAL SERVICE INDUSTRIES, INC. 3 Burwood Lane

San Antonio, Texas 78216 Phone: (210) 342-9377

Fax: (210) 342-9401

Professional Service Industries, Inc. • 3 Burwood Lane • San Antonio, TX 78216 • Phone (210) 342-9377 • Fax (210) 342-9401

March 1, 2018

City of San Antonio P.O. Box No. 839966 San Antonio, Texas 78283

Attn: Mr. Mark Beavers

RE: GEOTECHNICAL ENGINEERING REPORT PROPOSED FIRE STATION 54 FOSTER ROAD SAN ANTONIO, TEXAS PSI Project No. 0312-1609

Dear Mr. Beavers:

Professional Service Industries, Inc. (PSI) is pleased to submit this Geotechnical Engineering Report for the referenced project. This report includes the results of field and laboratory testing along with recommendations for use in preparation of the appropriate design and construction documents for this project.

PSI appreciates the opportunity to provide this Geotechnical Engineering Report and looks forward to continuing participation during the design and construction phases of this project. If there are any questions pertaining to this report, or if PSI may be of further service, please contact the PSI office.

PSI also has great interest in providing materials testing and inspection services during the construction of this project. If you will advise us of the appropriate time to discuss these engineering services, we will be pleased to meet with you at your convenience.

Respectfully submitted,

PROFESSIONAL SERVICE INDUSTRIES, INC. Texas Board of Professional Engineers Certificate of Registration # F003307 Dipta M. Joy, E.I.T. Richard E. Webb, P.E. Project Manager Principal Consultant Geotechnical Services 3/1/2018

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TABLE OF CONTENTS Page No.

1.0 PROJECT INFORMATION .................................................................................................................... 1

PROJECT AUTHORIZATION .................................................................................................................... 1 PROJECT DESCRIPTION ........................................................................................................................ 1 PURPOSE AND SCOPE OF SERVICES ..................................................................................................... 1

SITE AND SUBSURFACE CONDITIONS ............................................................................................ 3

SITE DESCRIPTION ................................................................................................................................ 3 FIELD EXPLORATION ............................................................................................................................. 3 LABORATORY TESTING PROGRAM ........................................................................................................ 4 SITE GEOLOGY ..................................................................................................................................... 4 SUBSURFACE CONDITIONS ................................................................................................................... 4

GEOTECHNICAL EVALUATION AND RECOMMENDATIONS ......................................................... 6

GEOTECHNICAL DISCUSSION ................................................................................................................ 6 POTENTIAL VERTICAL MOVEMENT OF EXPANSIVE SOILS ....................................................................... 6 FOUNDATION DISCUSSION .................................................................................................................... 7 DESIGN MEASURES TO REDUCE CHANGES IN SOIL MOISTURE ............................................................... 9 FOUNDATION DESIGN RECOMMENDATIONS ......................................................................................... 10 SITE SEISMIC DESIGN RECOMMENDATIONS ......................................................................................... 17

PAVEMENT DESIGN RECOMMENDATIONS ................................................................................... 18

PAVEMENT DESIGN PARAMETERS ....................................................................................................... 18 RIGID PAVEMENT SECTION RECOMMENDATIONS ................................................................................. 19

CONSTRUCTION CONSIDERATIONS .............................................................................................. 22 INITIAL SITE PREPARATION CONSIDERATIONS ..................................................................................... 22 MOISTURE SENSITIVE SOILS/WEATHER RELATED CONCERNS ............................................................. 23 BUILDING FOUNDATION EXCAVATION OBSERVATIONS ......................................................................... 23 DRAINAGE CONSIDERATIONS .............................................................................................................. 23 EXCAVATIONS AND TRENCHES ............................................................................................................ 23

REPORT LIMITATIONS ....................................................................................................................... 25 APPENDIX ......................................................................................................................................................... 26

Site Vicinity Map Boring Location Plan Boring Logs CBR Test Results Symbol Key Sheet

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INDEX OF FIGURES Page No.

Figure 3.1: Select Fill Pad Improvement .......................................................................................................... 8 Figure 3.2: Typical Stiffened Beam and Slab-on-Grade Section ................................................................ 10 Figure 3.3: Under-reamed Drilled Pier ........................................................................................................... 12 Figure 3.4: Straight-Shaft Drilled Pier ............................................................................................................ 14 Figure 4.1: Rigid Pavement Typical Section ................................................................................................. 19

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INDEX OF TABLES Page No.

Table 1.1: General Project Description ............................................................................................................ 1 Table 2.1 : Site Description ............................................................................................................................... 3 Table 2.2: Field Exploration Summary ............................................................................................................. 3 Table 2.3: Field Exploration Description ......................................................................................................... 3 Table 2.4: Generalized Soil Profile ................................................................................................................... 5 Table 3.1: Slab-on-Grade Earthwork Recommendations .............................................................................. 8 Table 3.2: Compaction Recommendations for Building Pad Preparation .................................................. 9 Table 3.3: WRI Design Parameters ................................................................................................................. 11 Table 3.4: PTI Design Parameters .................................................................................................................. 11 Table 3.5: Parameters for Axial Design ......................................................................................................... 12 Table 3.6: Constraints for Under-ream Pier Design ..................................................................................... 13 Table 3.7: Parameters for Axial Design ......................................................................................................... 14 Table 3.8: Constraints for Straight-Shaft Pier Design .................................................................................. 14 Table 3.9: Parameters for Lateral Design using LPILE ................................................................................ 15 Table 3.10: Drilled Pier Installation Considerations ..................................................................................... 15 Table 3.11: Recommended k Values .............................................................................................................. 17 Table 3.12: Recommended Design Seismic Parameters ............................................................................ 17 Table 4.1: California Bearing Ratio Test Summary ...................................................................................... 18 Table 4.2: Pavement Design Parameters and Assumptions ....................................................................... 18 Table 4.3: Rigid Pavement Roadway and Parking Area Section ................................................................ 20 Table 4.4: Pavement Design and Construction Recommendations .......................................................... 20 Table 4.5: Compaction and Testing Recommendations for Pavement Areas .......................................... 21 Table 5.1: Subgrade Preparation for Non-Structural - General Fill ............................................................ 22 Table 5.2: Fill Compaction Recommendations Outside of Building and Pavement Areas ..................... 22 Table 5.3: Considerations for Demolition ...................................................................................................... 22

Proposed Fire Station 54 PSI Project No: 0312-1609 Foster Road in San Antonio, Texas March 1, 2018

PROFESSIONAL SERVICE INDUSTRIES, INC. PAGE 1

1.0 PROJECT INFORMATION

PROJECT AUTHORIZATION

Professional Service Industries, Inc., (PSI) has completed a field exploration and geotechnical evaluation for the proposed Fire Station 54 project to be constructed at Foster Road in San Antonio, Texas. City of San Antonio authorized PSI’s by issuing Task Order #7032 to the On Call Geotechnical & Materials Testing Services contract between the City of San Antonio and PSI dted October 13, 2017. PSI’s Proposal No. 229040-R1, dated December 21, 2017 contained a proposed scope of work and fee.

PROJECT DESCRIPTION

Based on information provided and PSI’s review of two conceptual site plans titled “FIRE STATION NO. 54”, dated November 1, 2017 and prepared by Beaty Palmer Architects, a summary of the proposed project is presented in the following table.

TABLE 1.1: GENERAL PROJECT DESCRIPTION

Structure Fire station building with three (3) fire truck bays and associated access drives and parking areas

Structural Foot Print ± 6,636 SF

Construction Type Modular pre-engineered building

Existing Grade Change within Building Pad ± 2 feet estimated

Existing Grade Change within Project Site ± 12 feet estimated

Assumed Finished Floor Elevation 1 foot above the existing grade

Anticipated Foundation Type Shallow and deep foundation system

Assumed Maximum Column Loading Less than 200 kips

Assumed Maximum Wall Loading Less than 3.5 kips per lineal foot

The geotechnical recommendations presented in this report are based on the available project information, structure locations, and the subsurface materials described in this report. If any of the noted information or assumptions made are incorrect, please inform PSI so that the recommendations presented in this report can be amended as necessary. PSI will not be responsible for the implementation of provided recommendations if not notified of changes in the project.

PURPOSE AND SCOPE OF SERVICES

The purpose of this study is to evaluate the subsurface conditions at the site and develop geotechnical engineering recommendations and guidelines for use in preparing the design and other related construction documents for the proposed project. The scope of services included drilling borings, performing laboratory testing, and preparing this geotechnical engineering report.

This report briefly outlines the available project information, describes the site and subsurface conditions, and presents the following:

• A summary of the field and laboratory sampling and testing program. • Boring location plan.



• Boring logs and laboratory test results. • A review of general site conditions including descriptions of the site, the subsurface stratigraphy,

groundwater conditions, and the presence and condition of fill materials, if encountered. • Suitability of utilizing on-site materials as structural fill and backfill material. • Foundation design considerations and recommendations, including:

- expansive, soil-related movements using an empirical method for predicting Potential Vertical Rise (PVR) developed by the Texas Department of Transportation;

- methods for reducing expansive, soil-related movements; - soil profile type in accordance with the International Building Code - shallow foundation recommendations and allowable design values, if appropriate; - deep foundation recommendations and allowable design values, if appropriate; - lateral design parameters (LPILE) for use with deep foundation systems, if

necessary; - settlement estimations, where applicable; - uplift and allowable uplift resistance; and - groundwater considerations.

• Recommendations for heavy-duty and light-duty rigid pavement systems and pavement subgrade preparation recommendations.

• Construction considerations, including: - site drainage; - site preparation; and - select fill materials.

The scope of services for this geotechnical exploration did not include an environmental, mold nor detailed seismic/fault 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.



SITE AND SUBSURFACE CONDITIONS

SITE DESCRIPTION

The following table provides generalized descriptions of the existing site conditions based on visual observations during the field activities, as well as other available information.

TABLE 2.1 : SITE DESCRIPTION

Site Location Located approximately 330 feet northwest of the N Foster Road and Lancer Boulevard intersection

Existing Site Condition Undeveloped

Existing Grade/Elevation Changes Site slopes down approximately 12 feet to the northwest

Existing Site Ground Cover Grass and exposed subgrade

Ground Surface Soil Support Capability Firm enough to support field equipment

Site Boundaries

North: Undeveloped property East: North Foster Road, Undeveloped property South: Undeveloped property West: Undeveloped property

FIELD EXPLORATION

The soil conditions were explored by drilling a total of six (6) borings, located approximately as depicted on the Boring Location Plan provided in the Appendix. The boring design elements, boring labels, and approximate depths are provided in the following table.

TABLE 2.2: FIELD EXPLORATION SUMMARY Design Element Boring Label Approx. Depth of Boring

Fire Station Building B-1 and B-2 40 feet

Pavement P-1 through P-4 10 feet

The boring locations were selected by PSI personnel and were located in the field using available landmarks, GPS coordinates, and a recreational-grade GPS unit. Elevations of the ground surface at the boring locations were not available. If the elevations and boring locations are required, the boring elevations should be surveyed by others. Therefore, the references to elevations of various strata are based on depths below existing grade at the time of drilling.

TABLE 2.3: FIELD EXPLORATION DESCRIPTION Drilling Equipment Truck-Mounted Drilling Equipment

Drilling Method Continuous-Flight Auger

Drilling Procedure Applicable ASTM and PSI Safety Manual

Sampling Procedure ASTM D1587/1586

Field Testing Procedures Hand Penetrometers Standard Penetration Testing (ASTM D1586)

Frequency of Groundwater Level Measurements During drilling and at completion of drilling



Boring Backfill Procedures Soil Cuttings

Sample Preservation and Transportation Procedure General accordance with ASTM D4220

During the field activities, the encountered subsurface conditions were observed, logged, and visually classified (in general accordance with ASTM D2487). Field notes were maintained to summarize soil types and descriptions, water levels, changes in subsurface conditions, and drilling conditions.

LABORATORY TESTING PROGRAM

PSI supplemented the field exploration with a laboratory testing program to determine additional engineering characteristics of the subsurface soils encountered. The laboratory testing program included:

• Visual Classification (ASTM D2488),

• Moisture Content Tests (ASTM D2216),

• Atterberg Limits (ASTM D4318),

• Material Finer than No. 200 (ASTM D1140), and

• Unconfined Compression Strength Test (ASTM D2166).

The laboratory testing program was conducted in general accordance with applicable ASTM Test Methods. The results of the laboratory tests are provided in the Appendix on the Logs of Boring. Portions of samples not altered or consumed by laboratory testing will be retained for 60 days from the date shown this report and will then be discarded.

SITE GEOLOGY

As shown on the Geologic Atlas of Texas, San Antonio Sheet, the site is mapped as being located over the Midway Group (Emi) formation. The San Antonio Sheet generally describes the Midway Group (Emi) formation as containing clay and sand. The formation becomes more sandy and silty and grades to the mudstone and sand of Wilcox Group. The thickness of this formation is about 100 to 400 feet.

SUBSURFACE CONDITIONS

The results of the field and laboratory testing have been used to develop a generalized surface profile of the project site. The following subsurface descriptions highlight the major subsurface stratification features and material characteristics. This soil profile descriptions have been summarized in the following table.



TABLE 2.4: GENERALIZED SOIL PROFILE

Stratum Depth of Layer (ft)

Soil Type ω (%)

LL (%) PI

% Pass. #200 Top Bot.

I 0 4-6 Fat Clay and Fat Clay with Sand 15-34 59-91 43-60 76-79

II 4 6-8 Clayey Gravel with Sand 8-27 45-99 30-70 23-31

III 6-8 40 Lean Clay to Fat Clay 7-28 39-55 17-37 97

Notes: 1. ω – Water Content (%) 2. LL – Liquid Limit (%) 3. PI – Plasticity Index (%) 4. % Pass. #200 – Material Passing the No. 200 Sieve (%)

The boring logs included in the Appendix should be reviewed for information at individual boring locations. The boring logs include soil descriptions, stratifications, locations of the samples, and field and laboratory test data. The stratifications shown on the boring logs only represent the conditions at the individual boring location and represent the approximate boundaries between subsurface materials. The actual transitions between strata may be more gradual or more distinct. Variations will occur and should be expected across the site.

2.5.1 GROUNDWATER INFORMATION

The borings were advanced using dry drilling techniques to their full depths enabling the possibility of detection of the presence of groundwater. Groundwater was not encountered during the field exploration activities.

Groundwater levels fluctuate seasonally as a function of rainfall, proximity to creeks, rivers and lakes, the infiltration rate of the soil, seasonal and climatic variations and land usage. If more detailed water level information is required, observation wells or piezometers could be installed at the site, and water levels could be monitored.

The groundwater levels presented in this report are the levels that were measured at the time of our field activities. The contractor should be prepared to control groundwater, if encountered, during construction activities.



GEOTECHNICAL EVALUATION AND RECOMMENDATIONS

GEOTECHNICAL DISCUSSION

Based upon the information gathered from the soil borings and laboratory testing, the clay soils encountered at this site within the seasonally active zone have a high potential for expansion. PSI recommends the expansive potential (i.e. “Potential Vertical Movement” or PVM) of these soils be addressed in the design and construction of this project to reduce the potential for foundation movements and resulting distress.

The proposed Fire Station building can be supported on a stiffened beam and slab-on-grade provided that the expansive soil-related movements are mitigated to acceptable levels. The PVM for this type of foundation should be improved to approximately 1 inch. PSI recommends removal and replacement of a portion of the on-site soils with select structural fill to reduce the potential vertical movement of the foundation system.

The proposed structure can also be supported on under-reamed or straight-shaft drilled pier foundations. Our recommendations for these types of foundation systems are presented in the following report sections.

The following design recommendations have been developed based on the previously described project characteristics and subsurface conditions encountered. If there are any changes in the project criteria, PSI should be retained to review the changes and determine if modifications in the recommendations will be required. The findings of such a review would be presented in a supplemental report. Once final design plans and specifications are available, a general review by PSI is recommended to verify that the earthwork and foundation recommendations are properly interpreted and implemented within the construction documents.

POTENTIAL VERTICAL MOVEMENT OF EXPANSIVE SOILS

The soils encountered at the soil boring locations exhibit a high potential for volumetric changes, due to fluctuations in soil moisture content. PSI has conducted laboratory testing on the soils to estimate the expansive soil potential with soil moisture variations. These soil moisture variations are based on historical climate change data. Determining the soil potential for shrinking and swelling, combined with historical climate variation, aids the engineer in quantifying the soil movement potential of the soils supporting the floor slab and shallow foundations. Two soil modeling systems- the Post Tensioning Institute’s (PTI) “Design of Post-Tensioned Slabs-on-Ground, 3rd Edition” and Texas Department of Transportation (TxDOT) method TEX-124-E, were used to approximate the Potential Vertical Movement (PVM) for this location.

3.2.1 SHRINK/SWELL MOVEMENT (PVM) ESTIMATE

Based on laboratory testing results and TEX-124-E and the PTI methods, the potential vertical movement within the proposed project area was estimated to be approximately 2½ to 3 inches.

It is not possible to accurately quantify actual soil moisture changes and resulting shrink/swell movements. The PVM and referenced structural movements values provided should not be considered absolute values that could occur, but approximate values based on industry standard practice and experience. Extreme soil moisture variations could occur due to unusual drought severity, leaking water or sewer lines, poor drainage (possibly due to landscape changes after construction), irrigation line breaks, perched groundwater infiltration, springs, soil desiccation from



large trees located adjacent to the building or previously underneath the building, downspouts directing roof discharge under the foundation, etc. Therefore, because of these unknown factors, the shrink/swell potential of soils in Texas can often be significantly underestimated using the previously mentioned methods of evaluating PVM.

The unknown factors previously mentioned cannot be determined at the time of the geotechnical study. Therefore, estimated shrink/swell movements are calculated only in consideration of historical climate data related to soil moisture variations. Movements exceeding those estimated should be anticipated and regular maintenance should be provided to address these issues throughout the life of the structure.

3.2.2 DESIGN PVM CONSIDERATIONS

Grade-supported floor slabs and foundations should be expected to undergo some vertical movements, including differential, due to the action of expansive soils and possible soil settlement. In this general area, most owners, architects, structural and geotechnical engineers consider a value of one inch or less to be within acceptable movement tolerances for grade-supported floor slabs or foundations. PSI used this generally accepted tolerance for movement in developing the recommendations for preparing the building pad for this project.

The amount of structural movement associated with the PVM magnitude of one-inch may not be considered acceptable per “operational” or “aesthetic” performance criteria, which often occur at less movement than the magnitude of the PVM which is based on “structural” considerations. Cracking in the foundation and walls and sticking doors, which requires periodic maintenance, will likely occur for foundations designed using an allowable one-inch PVM. This should be understood by the Owner and Design Team.

PSI recommends that the Owner discuss allowable movement tolerances with the structural engineer, architect, and other members of the Design Team prior to commencement of the final design to make certain that appropriate movement tolerances are developed and used for this project. If design PVM values other than one inch is desired, PSI should be contacted to review and revise the recommendations presented in this report as necessary to meet the project requirements.

FOUNDATION DISCUSSION

Based on information provided to PSI, information obtained during the field operations, results of the laboratory testing, and PSI’s experience with similar projects, recommendations for a stiffened beam and slab-on-grade and drilled pier foundations are presented in this report. Should it be determined that different foundation types are desired, please inform PSI as soon as possible so that a supplement to this report for the desired foundation type can be provided.

A potential for vertical movement greater than 1 inch is above the value considered acceptable by most structural and geotechnical engineers in this area. Therefore, foundation improvement is recommended to reduce the PVM to an acceptable value for grade-supported floor slabs and shallow foundations used for this project.

3.3.1 SLAB-ON-GRADE EARTHWORK RECOMMENDATIONS

Building pad improvement should consist of removing the Stratum I dark brown soils to the recommended minimum over-excavation depth; compacting the exposed subgrade; and placement and compaction of select fill to achieve the finished floor grade. The following illustration and table



provide general requirements for the installation of a building pad that should provide a reduced potential for vertical movement and a structurally improved foundation system.

TABLE 3.1: SLAB-ON-GRADE EARTHWORK RECOMMENDATIONS

Site Stripping Removal Upper 6 inches of organics and deleterious material including debris to expose subgrade

Foundation Improvement Method Remove and replace existing soils with select fill

Improved Site Condition PVM Approximately 1 inch

Minimum Over-Excavation 4 feet or until the Stratum II Clayey Gravel is exposed

Horizontal Undercut Extent Below slab areas and at least 5 feet beyond the slab perimeter and extending the full width of flatwork that may be sensitive to movement

Proof-Rolling

The exposed subgrade should be proof-rolled with construction equipment weighing at least 20 tons. Soils that are observed to rut or deflect excessively under the moving load should be removed and replaced with properly compacted select fill materials.

Exposed Subgrade Treatment Proof-roll then scarify, moisture condition, and compact 9 inches natural subgrade

Minimum Select Fill Thickness 4 feet

Select Fill Material

Pit Run Free of organics, trash, or other deleterious material Liquid Limit <40% Plasticity Index 7 to 20 Max Particle Size < 3”

Vapor Retarder Material

Minimum 10-mil conforming to ASTM E1745, Class C or better and with a maximum water vapor permeance of 0.044 perms (ASTM E96) such as a 10 mil Stego Wrap by Stego Industries LLC or other similar product

Maximum Loose Lift Thickness 8 inches

Time Between Subgrade Prep. and Select Fill Placement Less than 48 hours

FIGURE 3.1: SELECT FILL PAD IMPROVEMENT

3.3.2 COMPACTION AND TESTING RECOMMENDATIONS FOR BUILDING PAD AREAS

The following table outlines building pad compaction recommendations in consideration of appropriate vertical movement reduction method.



TABLE 3.2: COMPACTION RECOMMENDATIONS FOR BUILDING PAD PREPARATION

Location Material Test Method for

Density Determination

Percent Compaction

Optimum Moisture Content

Testing Frequency

Building Pad Areas

Subgrade Soil ASTM D 698 ≥ 95% 0 to +4% 1 per 5,000 SF

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

DESIGN MEASURES TO REDUCE CHANGES IN SOIL MOISTURE

The following recommended measures can reduce possible moisture fluctuations of the soils under the floor slab. Movements of the foundation soil can be effectively reduced by providing horizontal and/or vertical moisture barriers around the edge of the slab. Typically, the moisture barriers would consist of concrete flatwork or asphalt or concrete pavement placed adjacent to the edge of the building, a clay cap over poly sheeting, and/or a deepened perimeter grade beam or vertical poly trench filled with flowable fill.

Although subgrade modification is recommended to reduce potential soil-related foundation movements, the design and construction of a grade-supported foundation should also include the following elements:

• Roof drainage should be controlled by gutters and carried well away from the structure.

• The ground surface adjacent to the building perimeter should be sloped and maintained a minimum of 5% grade away from the building for 10 feet to result in positive surface flow or drainage away from the building perimeter. In areas adjacent to the building controlled by ADA, concrete flatwork slopes should not be less than 2% within 10 feet of the building.

• Hose bibs, sprinkler heads, and other external water connections should be placed well away from the foundation perimeter such that surface leakage cannot readily infiltrate into the subsurface or compacted fills placed under the proposed foundations and slabs.

• No trees or other vegetation over 6 feet in height shall be planted within 15 feet of the structure unless specifically accounted for in the foundation design.

• Utility bedding should not include gravel near the perimeter of the foundation. Compacted clay or flowable fill trench backfill should be used in lieu of permeable bedding materials between 2 feet inside the building to 4 feet beyond the exterior of the building edge to reduce the potential for water to infiltrate within utility bedding and backfill material.

• Paved areas around the structure are helpful in maintaining soil moisture equilibrium. It will be very beneficial to have pavement, sidewalks or other flatwork located immediately adjacent to the building to both reduce intrusion of surface water into the more permeable select fill and to reduce soil moisture changes along the exterior portion of the floor due to soil moisture changes from drought, excessive rainfall or irrigation, etc. The use of a clay cap over poly sheeting (horizontal barrier) or impervious geosynthetic liner or concrete (vertical barrier) is recommended in those areas not covered with asphalt or concrete pavement or flatwork. For this project, the minimum recommended horizontal distance of relatively



impervious cover from pavement, flatwork or geosynthetic liner is 8 feet. For a deepened concrete beam or other type of impervious vertical barrier, a minimum depth of 6 feet is recommended.

• Flower beds and planter boxes should be piped or water tight to prevent water infiltration under the building.

• Experience indicates that landscape irrigation is a common source of foundation movement problems and pavement distress. Repairing irrigation lines as soon as possible after leakage commences will benefit foundation performance greatly.

• Building pad and pavement subgrade should be protected and covered within 48 hours to reduce changes in the natural moisture regime from rainfall events or excessive drying from heat and wind.

FOUNDATION DESIGN RECOMMENDATIONS

3.5.1 STIFFENED BEAM AND SLAB-ON-GRADE FOUNDATION RECOMMENDATIONS

FIGURE 3.2: TYPICAL STIFFENED BEAM AND SLAB-ON-GRADE SECTION

A stiffened beam and slab-on-grade foundation is generally used to support relatively light structures where soil conditions are relatively uniform and where uplift pressure and settlement can be tolerated. The intent of a stiffened beam and slab-on-grade foundation is to allow the structure and foundation to move with soil movements while providing sufficient stiffness to limit differential movements within the superstructure to an acceptable magnitude. The foundation may be designed using the Design of Slab-On-Ground Foundations published by the Wire Reinforcement Institute, Inc. (August 1981, updated March 1996). Alternately, the foundation may be designed using the 3rd Edition of the Design of Post-Tensioned Slabs-on-Ground published by the Post-Tensioning Institute (PTI DC10.1-08). The following table is applicable for a conventionally reinforced stiffened beam and slab-on-grade foundation with a building pad prepared in accordance with Section 3.3.1, which details building pad preparation and construction recommendations.



TABLE 3.3: WRI DESIGN PARAMETERS Effective Plasticity Index 25

Soil/Climatic Rating Factor (1–C) 0.11

Allowable Bearing Pressure for Grade Beams 3,000 psf

Bearing Stratum at Bottom of Grade Beams Minimum 12 inches of Compacted Select Fill Penetration of Perimeter Beams Below Final Exterior Grade Minimum 18 inches

PSI is providing PTI design values for the Structural Engineer’s consideration and possible use. These design values are estimated from the “Volflo” computer program in consideration of the soil conditions in the building area, an improved building pad for a 1-inch PVM and local experience. The following table is applicable for a conventionally reinforced or post-tensioned slab-on-grade with subgrade prepared in accordance with Section 3.3.1, which details building pad preparation and construction recommendations.

TABLE 3.4: PTI DESIGN PARAMETERS Edge Moisture Variation Distance Center Lift, em Edge Lift, em

9.0 feet 4.6 feet

Differential Soil Movement Center Lift, ym Edge Lift, ym

-0.79 inches 1.01 inches

Allowable Bearing Pressure for Grade Beams 3,000 psf

Bearing Stratum at Bottom of Grade Beams Minimum of 12 inches of Compacted Select Fill Penetration of Perimeter Beams Below Final Exterior Grade Minimum 18 inches

Utilities that project through slab and grade beam foundations should be designed either with some degree of flexibility or with sleeves to help prevent damage to these lines because of vertical movement. Contraction, control or expansion joints should be designed and placed in various portions of the structure to reduce and control wall cracking as a result of foundation movements. 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.

3.5.2 DRILLED PIER RECOMMENDATIONS

The proposed Fire Station building can also be supported on under-reamed or straight shaft drilled piers. The axial load carrying capacity of a drilled shaft can be computed using the static method of analysis. According to this method, axial capacity, Q, at a given penetration is taken as the sum of the skin friction on the side of the shaft, Qf, and the end or point bearing at the shaft tip, Qeb, so that:

Q = Qf + Qeb = f·As + q·Ap

where As and Ap represent, respectively, the embedded surface area and the end area of the shaft; f and q represent, respectively, the unit skin friction and the unit end or point bearing.



The total allowable axial capacity in compression will be the summation of the allowable frictional capacity and the allowable end bearing capacity. The total allowable axial capacity in tension will be the allowable frictional capacity alone neglecting end bearing component.

UNDER-REAMED DRILLED PIER

The following illustration and tables outline the recommendations for the drilled and under-reamed (belled) pier design and construction considerations.

FIGURE 3.3: UNDER-REAMED DRILLED PIER

TABLE 3.5: PARAMETERS FOR AXIAL DESIGN

Stratum Material Depth, feet

Allowable Skin Friction, Qf, psf

(F.S. = 2)

Allowable End Bearing, Qeb, psf

(F.S. = 3)

Uplift Force of

Soil, kips

I Clay 0 to 5 –– ––

40d with d in feet

II Clayey Gravel 5 to 8 –– ––

III Clay 8 to 25 1,100 12,000

III Clay 25 to 40 1,210 13,200



TABLE 3.6: CONSTRAINTS FOR UNDER-REAM PIER DESIGN Neglect Skin Friction from Top of Shaft 5 feet from top of shaft

Min. Embedment Depth Below Original Grade 18 feet

Minimum Shaft Diameter 18 inches

Maximum Bell to Shaft Ratio 2.5

Minimum Thickness to Neglect Skin Friction Belled Portion and 1 Pier Diameter from Base of Pier

Uplift Resistance 12 x (B2 – D2) Where: B is base diameter in feet D is shaft diameter in feet

Minimum Shaft Spacing (center to center) 3 Shaft Diameters (3∙d)

Possible Group Effect If spacing < 3d, consult Geotechnical Engineer

Min. Pier Vertical/Tensile Reinforcing Steel As Per ACI Code Estimated Settlement* Total Settlement Differential Settlement

Less than 1 inch Less than 0.5 inch

*Detailed Settlement Analysis is outside project scope

STRAIGHT-SHAFT DRILLED PIER

The following illustration and tables outline the recommendations for straight-shaft design and construction considerations for support of these structures.



FIGURE 3.4: STRAIGHT-SHAFT DRILLED PIER

TABLE 3.7: PARAMETERS FOR AXIAL DESIGN

Stratum Material Depth, feet

Allowable Skin Friction, Qf, psf

(F.S. = 2)

Allowable End Bearing, Qeb, psf

(F.S. = 3)

Uplift Force of

Soil, kips

I Clay 0 to 5 –– ––

40d with d in feet

II Clayey Gravel 5 to 8 –– ––

III Clay 8 to 25 1,100 12,000

III Clay 25 to 40 1,210 13,200

TABLE 3.8: CONSTRAINTS FOR STRAIGHT-SHAFT PIER DESIGN Neglect Skin Friction from Top of Shaft 5 feet

Minimum Embedment Depth below Original Grade 22 feet

Minimum Shaft Diameter, d 18 inches

Thickness to Neglect Skin Friction at Base of Shaft 1 Shaft Diameter



Uplift Resistance Pier Weight + Dead Load + Allowable Skin Friction Below Active Zone

Minimum Shaft Spacing (center to center) 3 Shaft Diameters (3∙d)

Possible Group Effect If spacing < 3d, consult Geotechnical Engineer

Min. Pier Vertical/Tensile Reinforcing Steel As Per ACI Code Estimated Settlement

Total Settlement Differential Settlement

Less than 1 inch Less than 0.5 inch

*Detailed Settlement Analysis is outside project scope

The minimum embedment depth was selected to locate the pier base below the depth of seasonal moisture change and within a specified desired stratum. Actual pier depths may need to be deeper depending upon the actual compressive loads on the pier.

LPILE DESIGN CRITERIA

Piers having lateral loads should be designed utilizing the following LPILE input parameters for this project.

TABLE 3.9: PARAMETERS FOR LATERAL DESIGN USING LPILE ‘p-y’

Criteria Depth,

feet γe, pcf

c, psf

φ, Deg.

ks or k, pci

kc, pci

ε50

Stiff Clay (Stratum I) 0-5 105 2,375 – 1,000 400 0.004

API Sand (Stratum II) 5-8 115 – 28 90 - -

Stiff Clay (Stratum III) 8-25 105 4,000 – 1,000 400 0.005

Stiff Clay (Stratum III) 25-40 105 4,500 – 2,000 800 0.004

Note: γe: Effective Soil Unit Weight c: Undrained Cohesion for Clay φ: Friction Angle for Sand ks: Clay Static Loading Modulus of Subgrade Reaction kc: Clay Cyclic Loading Modulus of Subgrade Reaction k: Sand Modulus of Subgrade Reaction ε50: Axial Strain Factor for Soil

GENERAL PIER CONSTRUCTION RECOMMENDATIONS

TABLE 3.10: DRILLED PIER INSTALLATION CONSIDERATIONS Recommended Installation Procedure FHWA-NHI-10-016, May 2010

High-Torque Drilling Equipment Anticipated No

Groundwater Anticipated No

Verification of Groundwater before Installation Yes

Temporary Casing Anticipated Possible due to Stratum II Clayey Gravel



Concrete Placement after Drilling

Same Day as drilling. If concrete cannot be poured the same day as excavation, temporary casing or slurry may be needed to maintain an open excavation. Concrete should not be allowed to ricochet off the pier reinforcing steel nor off the side walls of excavation.

Concrete Slump 7 inches ± 1 inch

Permissible Water Accumulation in Excavation Less than 2 inches Concrete Installation Method for Water Infiltration Tremie or pump to displace water

Reinforcing and Excavation to Cage Separation 3 times maximum size of coarse aggregate

Centralizers Recommended for Reinforcement Yes

Cross Bracing within Reinforcement Cage Not Recommended

Quality Assurance Monitoring by Geotechnical Engineer or Representative

Observe drilling of all piers During drilling, record tip of shaft depth Observe base material and cleanliness of base Observe placement of reinforcement

3.5.3 SLAB-ON-GRADE WITH A DRILLED PIER FOUNDATION

Slab-on-grade floor systems with drilled pier foundations have design consideration that should be considered. These design considerations are addressed in the following sections.

SLAB DIFFERENTIAL AND TOTAL VERTICAL MOVEMENT

Where movement sensitive flatwork will be constructed adjacent to the building, PSI recommends that the previously recommended building pad improvement be extended to include these locations. This action will reduce the PVM value in the flatwork areas and consequently reduce differential movements, associated with reversed drainage, door jamming, tripping hazards, etc. In addition, doweling the flatwork to the building foundation at common openings can further help 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. Grade-supported flatwork dowelled to more stable foundations should have connections designed to rotate and be flexible.

If the floor layout design allows for a one-inch vertical movement tolerance, then interior stiffening beams would not be required. In layouts with interior walls, a stiffened beam and slab-on-grade designed in accordance with WRI or PTI parameters should be incorporated into the design to provide additional stiffness to the floor system. In cases where vertical movement is anticipated, foundation beams should be placed under the walls, especially if the interior walls are CMU or other brittle material. The walls should incorporate sufficient vertical joints such that floor movement induced wall cracking is minimized. If the waffle slab design is not utilized, the building pad must be designed to only allow a one-half inch PVM and interior walls would still require beam support.

The foundation improvement for adjacent flatwork should extend the full width of the flatwork or at a minimum of at least 5 feet beyond the building parameter. Proper drainage around grade-supported sidewalks and flatwork is vital to reduce potential movements. Providing rapid, positive drainage away from the building will reduce moisture variations within underlying expansive soils and reduce the potential that the design PVM occurs.



GENERAL RECOMMENDATIONS FOR PIER SLAB-ON-GRADE

The design of grade-supported floor slab should take into consideration the interaction between the slab and the supporting soils to resist moments and shears induced by applied loads. Several design methods use the modulus of subgrade reaction, k, to account for soil properties. The k values presented in the following table can be used for the design of flat, grade-supported floor slabs for this project. These k values assume that at least 1.5 feet of the floor support material has been placed and properly compacted immediately beneath the slab.

TABLE 3.11: RECOMMENDED K VALUES Floor Support Material k, pci

Pit Run Select Fill 125

SITE SEISMIC DESIGN RECOMMENDATIONS

For the purposes of seismic design, based on the encountered site conditions and local geology, PSI interpreted the subsurface conditions to satisfy the Site Class D criteria for use at this site as defined by the International Building Code (IBC). The site class is based on the subsurface conditions encountered at the soil borings, the results of field and laboratory testing, 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.

TABLE 3.12: RECOMMENDED DESIGN SEISMIC PARAMETERS Seismic Parameter IBC 2015

0.2 sec (SS) 0.083g

1.0 sec (S1) 0.031g

Site Coefficient 0.2sec, Fa 1.6

Site Coefficient 1.0 sec, Fv 2.4

0.2 sec (SDS) 0.089g

1.0 sec (SD1) 0.050g



PAVEMENT DESIGN RECOMMENDATIONS

PAVEMENT DESIGN PARAMETERS

PSI understands that 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. PSI utilized the “AASHTO Guide for Design of Pavement Structures” published by the American Association of State Highway and Transportation Officials and the City of San Antonio Design Guidance Manual 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 (ESALs) that is applied to the pavement over its design life. In lieu of project specific design parameters, general trafficking and subgrade parameter assumptions were used for this design. Based on this information, PSI has provided recommended pavement sections for “light-duty” and “heavy-duty” pavements constructed on stable and properly prepared/compacted subgrades.

PSI collected one (1) bulk soil sample from the parking area to perform California Bearing Ratio (CBR) test. The CBR Test Results are presented in the Appendix. The following table presents the results of the CBR tests.

TABLE 4.1: CALIFORNIA BEARING RATIO TEST SUMMARY

Material ASTM D 698

Laboratory CBR Value Max

Dry Density Optimum Moisture Content

Fat Clay, dark brown 91.5 pcf 21.1% 2.8

Based on the provided information and CBR test results, PSI has provided recommended pavement sections constructed on stable and properly compacted subgrades. Details regarding the basis for this design are presented in the table below.

TABLE 4.2: PAVEMENT DESIGN PARAMETERS AND ASSUMPTIONS Reliability, percent 70

Initial Serviceability Index 4.5

Terminal Serviceability Index 2.0

Standard Deviation 0.35

Concrete Compressive Strength 4,000 psi

Subgrade Modulus of Subgrade Reaction, k in pci 75



Pavements supported on expansive soils will be subjected to PVM soil movements estimated and presented previously in this report. These potential soil movements are typically activated to some degree during the life of the pavement. Consequently, pavements can be expected to crack and require periodic maintenance to reduce damage to the pavement structure.

Light-duty areas include parking and drive lanes that are subjected to passenger vehicle traffic only and exclude entrance aprons and general and single access roadway drives to the parking lot area. Heavy-duty areas include areas subjected to fire trucks and 18-wheel tractor trailers, including loading and unloading areas, and areas where truck-turning and maneuvering may occur.

During the paving life, maintenance to seal surface cracks within concrete paving and to reseal joints within concrete pavement should be undertaken to achieve the desired paving life. Perimeter drainage should be controlled to prevent or retard influx of surface water from areas surrounding the paving. Water penetration leads to paving degradation. Water penetration into subgrade materials, sometimes due to irrigation or surface water infiltration leads to pre-mature paving degradation.

Material specifications, construction considerations, and section recommendations are presented in following sections.

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 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.

RIGID PAVEMENT SECTION RECOMMENDATIONS

Recommendations for rigid concrete pavement for roadways and parking areas are shown below.

FIGURE 4.1: RIGID PAVEMENT TYPICAL SECTION



TABLE 4.3: RIGID PAVEMENT ROADWAY AND PARKING AREA SECTION Materials Thicknesses

Traffic Type Light (1) Heavy

ESALs 15,000 550.000 1,430,000 3,250,000

Portland Cement Concrete 5” 6” 7” 8”

Lime Stabilized Subgrade 8” 8” 8” 8”

Note: 1. Automobile and light truck traffic only

4.2.1 GENERAL PAVEMENT DESIGN AND CONSTRUCTION RECOMMENDATIONS

TABLE 4.4: PAVEMENT DESIGN AND CONSTRUCTION RECOMMENDATIONS Minimum Undercut Depth 6 inches or as needed to remove roots

Reuse Excavated Soils Free of roots and debris and meet material requirements of intended use

Undercut Extent 2 feet beyond the paving limits

Exposed Subgrade Treatment Proof-roll with rubber-tired vehicle weighing at least 20 tons. A representative of the Geotechnical Engineer should be present during proof-roll.

Proof-Rolled Pumping and Rutting Areas Excavate to firmer materials and replace with compacted general or select fill under direction of a representative of the Geotechnical Engineer

General Fill Materials free of roots, debris, and other deleterious materials with a maximum rock size of 4 inches with a CBR greater than 3

Minimum General Fill Thickness As required to achieve grade

Maximum General Fill Loose Lift Thickness 9 inches

Lime Stabilization

Performed in general accordance with TxDOT Item 260. Upper 8 inches of subgrade stabilized with lime to achieve pH of 12.4 or greater. A lime series test should be performed at the time of construction to determine the lime requirement. Sulfate testing should also be conducted before placement of lime.

Concrete Minimum Recommended Strength 4,000 psi (28-day comp. strength)

Concrete Min. Recommended Reinforcement to Reduce Cracking

No. 4 bars at 18 inches on-center, each way Located in top half of concrete section Minimum 2 inches cover 14-inch long dowels spaced at 12 inches on-center at construction joints



TABLE 4.5: COMPACTION AND TESTING RECOMMENDATIONS FOR PAVEMENT AREAS



Percent Compaction


Testing Frequency

Pavement Areas

Scarified On-site Soil ASTM D 698 ≥ 95% 0 to +4% 1 per 7,500 SF; min. 3 tests

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

Base Material ASTM D 1557 ≥ 95% +3% 1 per 5,000 SF;

min. 3 per lift TEX-113-E ≥ 100% +2%



CONSTRUCTION CONSIDERATIONS

PSI should be retained to provide observation and testing of construction activities involved in the foundations, earthwork, pavements and related activities of this project. PSI cannot accept any responsibility for any conditions which deviate from those described in this report, nor for the performance of the foundations or pavements if not engaged to also provide construction observation and materials testing for this project. The PSI geotechnical engineer of record should also be engaged by the Design Team to provide continuing geotechnical engineering consulting services and construction document review, even if periodic on-call testing is contracted with PSI Construction Services.

INITIAL SITE PREPARATION CONSIDERATIONS

5.1.1 SUBGRADE PREPARATION FOR SITE WORK OUTSIDE BUILDING PAD AND PAVEMENT AREAS

Grade adjustments outside of the building pad and pavement areas can be made using select or general fill materials. The excavated on-site soils may also be reused in areas not sensitive to movement.

TABLE 5.1: SUBGRADE PREPARATION FOR NON-STRUCTURAL - GENERAL FILL

Minimum Undercut Depth 6 inches or as needed to remove roots, organic and/or deleterious materials

Exposed Subgrade Treatment Proof-roll with rubber-tired vehicle weighing at least 20 tons. A representative of the Geotechnical Engineer should be present during proof-roll.

Proof-Rolled Pumping and Rutting Areas Excavate to firmer materials and replace with compacted general or select fill under direction of a representative of the Geotechnical Engineer

General Fill Type Materials free of roots, debris and other deleterious material with a maximum particle size of 4 inches

Maximum General Fill Loose Lift Thickness 8 inches

TABLE 5.2: FILL COMPACTION RECOMMENDATIONS OUTSIDE OF BUILDING AND PAVEMENT AREAS



Percent Compaction


Testing Frequency

Outside of Structure or Pavement

Areas

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

5.1.2 EXISTING SITE CONDITIONS

The following table outlines construction considerations in consideration of removing trees.

TABLE 5.3: CONSIDERATIONS FOR DEMOLITION Tree Removal

Trees located within proposed building footprint; roadways, parking, and sidewalk areas; and 5 feet of building area

Remove root system for full vertical and lateral extent and extend removal for at least 3 feet beyond presence of root fragments and replace void with compacted general fill or flowable fill



MOISTURE SENSITIVE SOILS/WEATHER RELATED CONCERNS

Clay soils are sensitive to disturbances caused by construction traffic and changes in moisture content. During wet weather periods, increases in the moisture content of the soil can cause significant reduction in the soil strength and support capabilities. In addition, clay soils which become wet may be slow to dry and thus significantly retard the progress of grading and compaction activities. It will, therefore, be advantageous to perform earthwork, foundation, and construction activities during dry weather. A relatively all-weather compacted crushed limestone cap having a thickness of at least 6 inches may be considered as a working surface.

BUILDING FOUNDATION EXCAVATION OBSERVATIONS

The foundation excavations should be observed by a representative of PSI prior to reinforcing 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 exposed subgrades under the foundation. Soft or loose soil zones encountered at the bottom of the 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 or flowable fill.

After opening, 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 excavations must be left open an extended period, they should be protected to reduce evaporation or entry of moisture.

DRAINAGE CONSIDERATIONS

Water should not be allowed to collect in or adjacent to foundation excavations, on foundation surfaces, or on prepared subgrades within the construction area either during or after construction. Proper drainage around grade-supported sidewalks and flatwork is also important to reduce potential movements. Excavated areas should be sloped toward one corner to facilitate removal of any collected rainwater, groundwater, or surface runoff. Providing rapid, positive drainage away from the building will reduce moisture variations within the underlying soils and will therefore provide a valuable benefit in reducing the magnitude of potential movements.

EXCAVATIONS AND TRENCHES

Excavation equipment capabilities and field conditions may vary. Geologic processes are erratic and large variations can occur in small vertical and/or lateral distances. Details regarding “means and methods” to accomplish the work (such as excavation equipment and technique selection) are the sole responsibility of the project contractor. The comments contained in this report are based on small diameter borehole observations. The performance of large excavations may differ.

The Occupational Safety and Health Administration (OSHA) Safety and Health Standards (29 CFR Part 1926, Revised October 1989), require that excavations be constructed in accordance with the current OSHA guidelines. Furthermore, the State of Texas requires that detailed plans and specifications meeting OSHA standards be prepared for trench and excavation retention systems used during construction. PSI understands that these regulations are being strictly enforced, and if they are not closely followed, the owner and the contractor could be liable for substantial penalties.



The contractor is solely responsible for designing and constructing stable, temporary excavations and should shore, slope, or bench the sides of the excavations as required to maintain stability of both the excavation sides and bottom. The contractor's "responsible person", as defined in 29 CFR Part 1926, should evaluate the soil exposed in the excavations as part of the contractor's safety procedures. In no case should slope height, slope inclination, or excavation depth, including utility trench excavation depth, exceed those specified in local, state, and Federal safety regulations.

PSI is providing this information solely as a service to the client. PSI does not assume responsibility for construction site safety or the contractor's or other parties’ compliance with local, state, and Federal safety or other regulations. An excavation/trench safety plan was not part of PSI’s scope of services for this project.



REPORT LIMITATIONS

The recommendations submitted in this report are based on the available subsurface information obtained by PSI and design details furnished by the client for the proposed project. If there are any revisions to the plans for this project, or if deviations from the subsurface conditions noted in this report are encountered during construction, PSI should be notified immediately to determine if changes in the foundation recommendations are required. If PSI is not notified of such changes, PSI will not be responsible for the impact of those changes on the project.

The Geotechnical Engineer warrants that the findings, recommendations, specifications, or professional advice contained herein have been made in accordance with generally accepted professional Geotechnical Engineering practices in the local area. No other warranties are implied or expressed. This report may not be copied without the expressed written permission of PSI.

After the plans and specifications are more complete, the Geotechnical Engineer should be retained and provided the opportunity to review the final design plans and specifications to check that the engineering recommendations have been properly incorporated in the design documents. At this time, it may be necessary to submit supplementary recommendations. If PSI is not retained to perform these functions, PSI will not be responsible for the impact of those conditions on the project.

This report has been prepared for the exclusive use of City of San Antonio for specific application to the proposed Fire Station 54 to be constructed at Foster Road in San Antonio, Texas.

APPENDIX

Proposed Fire Station 54February, 2018Foster Road

Date

SITE VICINITY MAP

Project Name and Location PSI Project No.

0312-1609San Antonio, Texas

Project Site

BORING LOCATION PLAN

Project Name and Location PSI Project No.

Drawing Not-to-Scale

0312-1609

San Antonio, Texas

Proposed Fire Station 54

February, 2018Foster Road

Date

(Boring Locations are Approximate)

B-1

P-2

B-2

P-1

P-4P-3

53

106

77

45

39

27

27

10

14

28

26

17

18

23

22

24

20

15

22

FAT CLAY with SAND (CH), darkbrown, stiff to very stiff

CLAYEY GRAVEL with SAND (GC),brown, medium dense

LEAN CLAY to FAT CLAY (CL-CH),greenish gray to light brown, very stiffto hard

Boring terminated at an approximatedepth of 40 feet.

57

30

17

20

2.64

23

97

DEPTH TO GROUND WATER

WC

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ST

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COMPLETION DEPTH: 40.0 Feet

20 40 60PLA

ST

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%R

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BORING B-1

END OF DRILLING (ft.): NONE OBSERVEDSEEPAGE (ft.): NONE ENCOUNTERED

Elevation: N/A

LOCATION: See Boring Location Plan

DELAYED WATER LEVEL (FT): N/A

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DATE: 1/26/18-1/26/18

2.0 4.0 6.0W

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30

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PROPOSED FIRE STATION 54Foster Road, San Antonio, texas

Project No. 0312-1609

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CLAYEY GRAVEL with SAND (GC),brown to light brown, medium dense todense

LEAN CLAY to FAT CLAY (CL-CH),greenish gray to light brown, hard


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CLAYEY GRAVEL with SAND (GC),brown to light brown, medium dense todense

LEAN CLAY to FAT CLAY (CL-CH),greenish gray to light brown, very stiff


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SOIL DESCRIPTION

% P

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200

5

10

15

20

25

30

35

40

% R

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SY

MB

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SP

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Maximum Laboratory Dry Density

CBR @ 95% TEST DATE PSI PROJECT NUMBER

Proposed Fire Station 54Foster Road

San Antonio, Texas

2/19/2018 0312-1609

96.4 pcf

2.8

10 blows/lift

25 blows/lift

56 blows/lift

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

70.00 72.00 74.00 76.00 78.00 80.00 82.00 84.00 86.00 88.00 90.00 92.00 94.00

Calif

orni

a Be

arin

g Re

atio

(CBR

)

Dry Unit Weight as Molded (pcf)

CBR vs. Dry Molded Unit Weight (pcf)

95% Max Dry Density= 91.58 pcf

CBR = 2.8

Clay (CH)

Inclusion of different material less than 1/8 inch thick extending through the sample.Partings

Weathering as a percentage.

Clayey Silt (ML)

Conglomerate

Gravel (GP or GW)Silty Gravel (GM)Sandy Gravel (GP)Clayey Gravel (GC)Concrete

Material Symbols

Sandy Silt (ML)

"FILL"

Base

Gravelly Sand (SP)Silty Sand (SM)Sand (SP)Clayey Sand (SC)Asphalt

Sandy Clay (CL)

Blows Per Foot

Silt (ML)

Interbedded

SlickensidedInclusion of different material between 1/8 and 3 inches thick, and extends through the sample.

SPT Sample

The ratio of total length of recovery to the total length of core run, expressed as a percentage.

Nodules

to be randomly oriented.

Composed of alternating layers of different soil types.

UndisturbedShelby Tube (3")

vertical in orientation.Contains shrinkage cracks, which are frequently filled with fine sand or silt. The fissures are usually near

Composed of thin layers of varying color and texture.

Very Loose

Note: Driving is limited to 50 blows per interval, or 25 blows for 0.25 inch advancement, whichever controls. This is done to avoid damaging sampling tools.Standard Penetration Test (ASTM D 1586) Driving Record

more than 5030 to 5010 to 30 4 to 10

less than 4Count (blows/ft)

Has inclined planes of weakness that are slick and glossy in appearance. Slickensides are commonly thought

Loose

Descriptive Term

Density of Granular Soils

% RecoveryA natural break along which no displacement has occurred, and which generally intersects primary surfaces.JointA natural break in rock along which no displacement has occurred.

Rock TermsStains of limited extent that appear as short stripes, spots or blotches.Streaks or Stains

SPT BlowStrength, KSF

Sampler was seated 6 inches, 25 blows were required for the second 6 inch increment andthe 50 blow limit was reached at 2 inches of the last increment.

Ref/2"

75/8"

Laminated

Seams

5 to 10

1.00 to 2.000.50 to 1.00

less than 0.25

RQD - Rock Quality

Undrained Shear

HardVery StiffStiffFirmSoftVery Soft

Consistency

Shale

0.25 to 0.50

Gravelly Silt (ML)

FractureA surface parallel to the surface of deposition, generally marked by changes in color or grain size.Bedding Plane

DisturbedShelby Tube (3")

Core Barrel

Inclusion of different material that is smaller than the diameter of the sample.Pockets

Designation

Secondary inclusions that appear as small lumps about 0.1 to 0.3 inch in diameter.

Strength of Cohesive Soils

Grab SampleNo RecoveryFlight Auger

Sampler Symbols

The process by which rock is broken down and decomposed.

Very DenseDenseMedium Dense

The ratio of total recovered length of fragments longer than 4 inches to the total run length, expressed

Limestone

Symbol Key Sheet

Sandstone

NonePlasticityDegree of

Soil Plasticity

greater than 4.002.00 to 4.00

ModeratePlastic

Lean Clay (CL)

Sampler was seated 6 inches, then 25 blows were required to advance the sampler 12 inches.

Silty Clay (CL)

Fissured

Sampler could only be driven 2 inches of the 6 inch seating penetration before the 50 blow limit was reached.

Contains appreciable quantities of calcium carbonate.CalcareousContains cracks or failure planes resulting in rough cubes of material.Blocky

Description

Low

Terms Characterizing Structure

Marl

25Description

more than 4020 to 4010 to 20

0 to 5Index (PI)Plasticity

Highly Plastic

Soil Terms

913468

New Stamp

Environmental Consulting& Geotechnical ServicesAssuring site and subsurface conditions meet the criteria forpurchase, development and construction.

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Product Certification& CodeEvaluationThe ETL and Warnock Hersey Marks show a product or system’s conformance to code and ensures the on-going verification of compliance.

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Building EnclosureCommissioningDesign and construction professionals provide solutions to reduce the potential for premature building failure, increase a building’s energy efficiency, and expected life cycle.

Property Management Support ServicesProviding a variety of building systems testing, inspection, and consulting services to optimize the value and life of the property asset.

Mock-Up & Field TestingOn-site (air infiltration, water leakage, and structural performance for fenestration) or in lab validation of a curtain wall’s design, workmanship, and material selection to ensure its performance

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BPFSNA30-2

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IQP

Professional Service Industries, Inc. (PSI)IntertekMT Group

[email protected]

Offices Nationwide & International

www.psiusa.com www.intertek.com/building

Contact

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