Division D Geotechnical Report - San Antonio

CITY OF SAN ANTONIO DIVISION D STINSON MUNICIPAL AIRPORT GEOTECHNICAL REPORT STINSON MONUMENT AND DIRECTIONAL SIGNAGE

DIVISION D

Division D

Geotechnical Report

CITY OF SAN ANTONIO DIVISION D STINSON MUNICIPAL AIRPORT GEOTECHNICAL REPORT STINSON MONUMENT AND DIRECTIONAL SIGNAGE

DIVISION D

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Geotechnical Engineering Study

Stinson Airport Monument and Directional Signage

San Antonio, Texas

Arias Job No. 2016-426

Prepared For

Gonzalez De La Garza

August 22, 2017

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TABLE OF CONTENTSPage

Arias Geoprofessionals i Arias Job No. 2016-426

INTRODUCTION................................................................................................................... 1

SCOPE OF SERVICES......................................................................................................... 1

PROJECT DESCRIPTION .................................................................................................... 1

FIELD EXPLORATION.......................................................................................................... 1

LABORATORY TESTING ..................................................................................................... 2

SUBSURFACE CONDITIONS............................................................................................... 2 Geology............................................................................................................................. 2 Site Stratigraphy and Engineering Properties .................................................................... 3 Groundwater...................................................................................................................... 5

DESIGN RECOMMENDATIONS AND DRILLED SHAFT INSTALLATION............................ 5 Potential Expansive Soil Movements ................................................................................. 5 Straight-Shaft Drilled Shafts .............................................................................................. 6 Lateral Pile Capacity.........................................................................................................10 Drilled Shaft Construction Considerations.........................................................................12 IBC Site Classification and Seismic Design Coefficients...................................................14

CONSTRUCTION CRITERIA ...............................................................................................14 Drainage...........................................................................................................................14 Trench Excavations ..........................................................................................................15

GENERAL COMMENTS ......................................................................................................15 Geotechnical Design Review............................................................................................15 Subsurface Variations ......................................................................................................15 Quality Assurance Testing................................................................................................15 Standard of Care ..............................................................................................................16

APPENDIX A: FIGURES AND SITE PHOTOGRAPHS .................................................A-1

APPENDIX B: BORING LOGS AND KEY TO TERMS ..................................................B-1

APPENDIX C: FIELD AND LABORATORY EXPLORATION .........................................C-1

APPENDIX D: GRAIN SIZE DISTRIBUTION CURVES .................................................D-1

APPENDIX E: PLANS AND ELEVATIONS OF MONUMENT SIGNS............................E-1

APPENDIX F: ASFE INFORMATION – GEOTECHNICAL REPORT ............................ F-1

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TABLE OF CONTENTSPage

Arias Geoprofessionals ii Arias Job No. 2016-426

APPENDIX G: PROJECT QUALITY ASSURANCE .......................................................G-1

TablesTable 1: Generalized Soil Conditions and Soil Properties - Boring B-1 ................................. 3 Table 2: Generalized Soil Conditions and Soil Properties - Boring B-2 ................................. 4 Table 3: Generalized Soil Conditions and Soil Properties - Boring B-3 ................................. 4 Table 4: Groundwater Measurements in Borings.................................................................. 5 Table 5: Drilled Shaft Design Parameters for Axial Loading – Boring B-1............................. 7 Table 6: Drilled Shaft Design Parameters for Axial Loading – Boring B-2............................. 8 Table 7: Drilled Shaft Design Parameters for Axial Loading – Boring B-3............................. 9 Table 8: Geotechnical Input Parameters for Lpile Analyses at Boring B-1 ...........................10 Table 9: Geotechnical Input Parameters for Lpile Analyses at Boring B-2 ...........................11 Table 10: Geotechnical Input Parameters for Lpile Analyses at Boring B-3 .........................12 Table 11: Drilled Shaft Installation Considerations...............................................................13 Table 12: Seismic Design Parameters.................................................................................14

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Arias Geoprofessionals 1 Arias Job No. 2016-426

INTRODUCTION

This report presents the results of a Geotechnical Engineering Study for the proposed Monument and Directional Signs at Stinson Airport in San Antonio, Texas. A Vicinity Map is included as Figure 1 in Appendix A.

This project was authorized by means of Standard Agreement for Professional Services Contract No. 4600014506 (TO-0000020); between Gonzalez De La Garza and Arias Geoprofessionals (Arias), effective May 26, 2016. Our scope of services was performed in general accordance with revised Arias Proposal No. 2016-426, dated June 14, 2016 (revised April 19, 2017).

SCOPE OF SERVICES

The purpose of this geotechnical engineering study was to perform a subsurface exploration and laboratory testing to: (1) establish engineering properties of the subsurface soil and groundwater conditions present on the site and (2) develop drilled shaft foundations design parameters for monument and directional signs.

Environmental studies were not a part of our scope of services. Our scope of work did not include evaluating foundations for walls.

PROJECT DESCRIPTION

Arias previously submitted a geotechnical report dated March 31, 2017 that presented mat foundation and earthwork recommendations for the monument signs at Stinson Municipal Airport in San Antonio, Texas. The Project has since expanded to include directional signsthat are to be supported on drilled shaft foundations. In addition, Arias has been requested to provide recommendations for the support of monument signs on drilled shafts. Landscaping will be installed between the monument sign and the low wall and in front of the low walls.Plans and elevation profiles of monument signs (obtained from project design team) are presented in Appendix E.

FIELD EXPLORATION

Two (2) soil borings were drilled and sampled for monument signs at the approximate locationsshown on the Boring Location Plan provided as Figure 2 in Appendix A. The borings were each drilled to a depth of approximately 15 feet, which was measured from below the existing ground surface on March 1, 2017. Since the project design team requested recommendations for supporting the signs and monuments on drilled piers, we performed additional drilling on July 15, 2017 to extend the previous borings to a depth of 25 feet. At the same time, we drilled a boring to a depth of 25 at the proposed directional sign.

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The borings were sampled in accordance with ASTM D1587 for thin-walled tubes and ASTM D1586 for Split Spoon sampling techniques as described in Appendix C. A truck-mounted drill rig using continuous flight augers together with the sampling tool noted was used to secure the subsurface soil samples.

Soil classifications and borehole logging were conducted during the exploration by one of our field-logging technicians, who is under the supervision of the project Geotechnical Engineer. Final soil classifications, which are presented on the borings logs in Appendix B, were determined based on field observations and the results of laboratory tests performed in accordance with applicable ASTM procedures. After completion of drilling, the open boreholes were backfilled using soil cuttings generated during drilling operations.

LABORATORY TESTING

As a supplement to the field exploration, laboratory testing was conducted to determine soil moisture content, Atterberg Limits, percent passing the US Standard No. 200 sieve andunconfined compressive strength. The laboratory results are reported on the boring logs included in Appendix B, and are plotted as Grain Size Distribution Curves in Appendix D.

A key to the terms and symbols used on the logs is also included in Appendix B. The laboratory testing was done in accordance with applicable ASTM procedures with the specifications and definitions for these tests listed in Appendix C.

Remaining soil samples recovered from this exploration will be routinely discarded following submittal of this report.

SUBSURFACE CONDITIONS

Geology, generalized soil stratigraphy, and groundwater conditions at the project site are discussed in the following sections. The subsurface and groundwater conditions are based on conditions encountered at the boring locations to the depth explored.

GeologyA Geologic Map is included as Figure 3 in Appendix A. The earth materials underlying the project site have been regionally mapped as Fluviatile Terrace Deposits (Qt). Fluviatile Terrace Deposits are alluvial soils consisting of clays and granular soils (i.e. sand or gravel) containing various amounts of clay, silt, sand, and/or gravel. The geotechnical engineering considerations for these types of deposits include the potential for significant variations over short distances and the potential of expansive clays being present.

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Site Stratigraphy and Engineering PropertiesThe general stratigraphic conditions and at the boring locations are provided subsequently in Tables 1, 2 and 3 at Borings B-1, B-2 and B-3, respectively. The presence and thickness of the various subsurface materials can be expected to vary away from and between the exploration locations. The descriptions conform to the Unified Soils Classification System(ASTM D 2487).

Table 1: Generalized Soil Conditions and Soil Properties - Boring B-1

Depth(feet) Material Type PI

RangeNo. 200

Range

N-valueRange

PPRange,

tsfUc

Range

0 to 4SANDY FAT CLAY (CH); very stiff; dark brown to brown; with occasional clayey sand seams

and calcareous material

*39 *44 -- 3.0 to 4.5+ *2.95

4 to 8CLAYEY GRAVEL with sand(GC); dense; light brown and

brown*20 *21 16 - 50 -- --

8 to 10LEAN CLAY (CL); very hard; light

brown *15 *90 *91/10” -- --

10 to 18CLAYEY SAND with gravel (SC);

very dense to medium dense; light brown to brown

-- *27 27 –50/6” -- --

18 to 23SANDY LEAN CLAY (CL); very

stiff; tan *14 -- -- -- --

23 to 25SILTY CLAYEY SAND (SC-SM);

dense; tan and brown *5 34 45 -- --

Where: Depth - Depth from existing ground surface during geotechnical study, feetPI - Plasticity Index, %No. 200 - Passing #200 sieve, %N - Standard Penetration Test (SPT) value, blows per foot or inches if notedUc - Unconfined compressive strength, tsf PP - Pocket Penetrometer Value, tsf* - Only one test performed-- - No Test

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Table 2: Generalized Soil Conditions and Soil Properties - Boring B-2Depth(feet) Material Type PI

RangeNo. 200 Range

N-valueRange

UcRange

0 to 4 SANDY FAT CLAY (CH); very stiff to stiff; dark brown *40 *66 *10 *2.87

4 to 6 CLAYEY GRAVEL with sand (GC);medium dense to dense; tan & brown *20 *22 -- --

6 to 18 CLAYEY SAND with gravel (SC); loose to very dense; brown and tan 18 - 22 30 - 38 3 - 69 --

18 to 23CLAYEY GRAVEL (GC); dense; tan

and brown *43 *40 *45 --

23 to 25FAT CLAY (CH); very stiff; tan and

brown *48 *95 *24 --

Where: Depth - Depth from existing ground surface during geotechnical study, feetPI - Plasticity Index, %No. 200 - Passing #200 sieve, %N - Standard Penetration Test (SPT) value, blows per foot or inches if notedUc - Unconfined compressive strength, tsf * - Only one test performed-- - No Test

Table 3: Generalized Soil Conditions and Soil Properties - Boring B-3

Depth(feet) Material Type PI

RangeNo. 200

Range

N-valueRange

PPRange,

tsfUc

Range

0 to 6 SANDY LEAN CLAY (CL); stiff tohard; dark brown to brown *21 *62 *8 4.0 *6.05

6 to 18CLAYEY SAND with Gravel (SC); medium dense to dense; brown

and tan*24 *24 23 - 41 --

18 to 23SILTY, CLAYEY SAND with

Gravel and (SC-SM); very dense; brown and tan

*4 *30 *71 -- --

23 to 25CLAYEY GRAVEL with sand

(GC); very dense; tan and brown *25 *28 *59 -- --

Where: Depth - Depth from existing ground surface during geotechnical study, feetPI - Plasticity Index, %No. 200 - Passing #200 sieve, %N - Standard Penetration Test (SPT) value, blows per foot or inches if notedPP - Pocket Penetrometer value, tsfUc - Unconfined compressive strength, tsf * - Only one test performed-- - No Test

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GroundwaterA dry soil sampling method was used to obtain the soil samples at the project site. Groundwater was not encountered during the drilling of Borings B-1 and B-2 on March 1, 2017. However, groundwater was observed in all three borings during our drilling on July 15, 2017. A summary of groundwater information is presented in the following table.

Table 4: Groundwater Measurements in Borings

Boring No.Groundwater Depths (feet)

During Drilling After Completion

B-1 24.0 23.2

B-2 23.0 22.8

B-3 23.3 22.8

Note: Depth is measured from existing ground surface at the time of drilling on July 15, 2017.

Groundwater levels will often change significantly over time and should be verified immediately prior to construction. Water levels in open boreholes may require several hours to several days to stabilize depending on the permeability of the soils. Groundwater levels at this site may differ during construction because fluctuations in groundwater levels can result from seasonal conditions, rainfall, drought, or temperature effects. Pockets or seams of gravels, sands, silts or open fractures and joints can store and transmit “perched” groundwater flow or seepage. Should dewatering become necessary during construction, it is considered “means and methods” and is solely the responsibility of the Contractor.

DESIGN RECOMMENDATIONS AND DRILLED SHAFT INSTALLATION

Potential Expansive Soil MovementsThe dark brown sandy fat clay (CH), which was encountered in borings B-1 and B-2 to a depth of about 4 feet, has high shrink-swell characteristics. The dark brown sandy lean clay (CL), which was encountered in boring B-3 to a depth of about 4 feet, has moderate shrink-swell characteristics. Expansive clay materials shrink when they lose water and swell or grow in volume when they gain water content. The potential of expansive soils to shrink and swell is related to the Plasticity Index (PI). Clayey soils with a higher PI have a greater potential for soil volume changes due to moisture content variations. Change in soil moisture is the single most important factor affecting the shrinking and swelling of clays. The most pronounced movements are commonly observed when soils are exposed to extreme moisture fluctuations that occur between drought conditions and wet seasons.

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At Borings B-1 and B-2, we estimate the potential vertical rise (PVR) to be about 2½ inchesat Borings B-1 and B-2 and about 2 inches at boring B-3 using the Tex-124-E method outlined by the Texas Department of Transportation (TXDOT). This method provides an estimate of the PVR using the liquid limits, plasticity indices, and existing water contents.

The PVR is estimated in the seasonally active zone, which is assumed to be 15 feet based upon assumed changes in soil moisture content from a dry to a wet condition. However, soil movements in the field depend on the actual changes in moisture content. Thus, actual soil movements could be less than that calculated if little soil moisture variations occur, or the actual movement could exceed the estimated values if actual soil moisture content changes exceed the assumed dry and wet limits outlined by the PVR method. Such moisture conditions that deviate from the limits of the PVR method may be the result of extended droughts, flooding, perched groundwater infiltration, poor surface drainage, and/or leaking irrigation lines.

Straight-Shaft Drilled ShaftsThe monument and directional signs are expected to transmit relatively light axial compression loading to the proposed straight-sided drilled shafts. The drilled shafts will also be subject to: (1) lateral loading; and (2) tension loading due to wind-induced uplift forces and potential uplift loading induced on the upper 4 feet of the shafts due to expansive soil-related heaving. Accordingly, the drilled shafts will need to be anchored adequately below the zone of seasonal moisture change to resist uplift loading.

Drilled shafts should be designed in accordance with the allowable side friction (i.e. compression and tension loading) and end bearing values given subsequently in Tables 5, 6, and 7 at Borings B-1, B-2, and B-3, respectively. The design methodology for developing allowable values and associated factors of safety together with other pertinent information is provided in the “Notes” given below the tables.

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Table 5: Drilled Shaft Design Parameters for Axial Loading – Boring B-1

Depth (feet) Material

Recommended Design ParametersAllowable

Skin Friction psf

Allowable End

Bearing psf

Uplift Forcekips

0 - 4 Very Stiff SANDY FAT CLAY Neglect ---

20*D

4 - 8 Medium Dense to Dense CLAYEY GRAVEL with SAND 500 ---

8 -10 Very Hard LEAN CLAY 1,000 --

10 - 18 Very Dense to Medium Dense CLAYEY SAND with GRAVEL 800 --

18 - 23 Very Stiff to Hard SANDY LEAN CLAY 800 9,000

23 - 25 Dense SILTY CLAYEY SAND 500 10,000

Constraints to be Imposed During Pier Design

Minimum embedment depth 20 feet(See note 2)

Minimum Spacing Center to Center 3 shaft diameters

Minimum shaft diameter 18 inches

Notes:1. The depths provided are below the existing ground surface at the time of the borings.

2. Shafts should be a minimum diameter of 18 inches, and be spaced a minimum of 3 shaft diameters center to center. The minimum embedment depth of 20 feet was selected to anchor the drilled shaftssufficiently below the expansive clay, which has the potential to impose uplift forces due to soil heaving. If shafts are extended to depths greater than 20 feet, there is a progressively risk for encountering groundwater, which was measured at a depth of about 23 feet at the time of the borings.

3. Shaft capacities were evaluated based on design methodologies included in FHWA-IF-99-025 - Drilled Shafts: Construction Procedures and Design Methods. Both end bearing and side friction resistance may be used in evaluating the allowable bearing capacity of the pier shafts for the strata shown above.Recommended design parameters include a factor of safety of 2 for skin friction and of 3 for end bearing.For compression loading, frictional resistance is neglected in the upper 4 feet and for a length equal to 1 pier diameter from the bottom of the shaft.

4. The uplift force in kips resulting from expansion of soils in the active zone may be computed using the above formula where D is the shaft diameter in feet. Uplift resistance along the shaft can be used from a depth of 4 feet to the bottom of the shaft. Sustained dead loads will also aid in resisting uplift forces.

5. Sufficient reinforcing steel should be placed within the pier to account for tension and lateral loading as applicable. Vertical steel should be a minimum of 1% of the gross cross-sectional area of the shaft; however, the final reinforcing requirements should be determined by the project structural engineer. Tensile rebar steel should be designed in accordance with ACI Code Requirements.

6. Total and differential settlement of drilled shafts is expected to be less than 1 inch and ½ inch, respectively. Estimated settlements are based on performance of properly installed piers in the South Texas areas. A detailed settlement estimate is outside of the scope of this service.

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Skin Friction psf

Allowable End

Bearing psf

Uplift Forcekips

0 - 4 Very Stiff to Stiff SANDY FAT CLAY Neglect ---

20*D

4 - 6 Medium Dense to Dense CLAYEY GRAVEL with SAND 400 ---

6 - 13 Loose CLAYEY SAND with GRAVEL 200

13 -18 Very Dense CLAYEY SAND with GRAVEL 800 --

18 - 23 Dense CLAYEY GRAVEL with SAND 800 12,000

23 - 25 Very Stiff FAT CLAY 800 9,000











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Skin Friction psf

Allowable End

Bearing psf

Uplift Forcekips

0 - 6 Stiff to Hard SANDY FAT CLAY Neglect ---

20*D6 -18 Medium Dense to Dense CLAYEY SAND with GRAVEL 600 --

18 - 23 Very Dense SILTY, CLAYEY SAND with GRAVEL 800 12,000

23 - 25 Very Dense CLAYEY GRAVEL with SAND 800 12,000











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Lateral Pile CapacityLateral pile analyses including capacity, maximum shear, and maximum bending moment will be evaluated by the project structural engineer using Lpile or similar software. In Tables 8 to10 given subsequently, Arias presents geotechnical input parameters for the encountered soils in Borings, B-1, B-2 and B-3, respectively. The depths to the top and bottom of each layer were interpreted using data developed at the explored boring locations and layer boundaries as shown on the logs for the respective borings.

Table 8: Geotechnical Input Parameters for Lpile Analyses at Boring B-1

Depth(ft)

MaterialLPILE SoilType

e CuK

Static e50

0 - 4 Very Stiff SANDY FAT CLAY 3 0.069 6.94 0 250 0.009

4 - 8Medium Dense to Dense CLAYEY

GRAVEL with SAND4 0.069 0 32 90 --

8 -10 Very Hard LEAN CLAY 3 0.072 27.8 -- 1,000 0.005

10 - 18Very Dense to Medium Dense CLAYEY SAND

with GRAVEL4 0.072 -- 32 225 --

18 - 23 Very Stiff to Hard SANDY LEAN CLAY 3 0.072 27.8 0 1,000 0.005

23 - 25 Dense SILTY CLAYEY SAND 4 0.036 0 32 125 --

Where: e = effective soil unit weight, pci

cu = undrained soil shear strength, psi= undrained angle of internal friction, degrees

K = modulus of subgrade reaction, pcie50 = 50% strain value

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Depth(ft)

MaterialLPILE Soil Type

e CuK

Static e50

0 - 4 Very Stiff to Stiff SANDY FAT CLAY 3 0.069 6.94 0 250 0.009

4 - 6Medium Dense to Dense CLAYEY

GRAVEL with SAND4 0.069 0 32 125 --

6 - 13 Loose CLAYEY SAND with GRAVEL 4 0.066 0 28 25 --

13 -18 Very Dense CLAYEY SAND with GRAVEL 4 0.072 -- 32 225 --

18 - 23 Dense CLAYEY GRAVEL with SAND 4 0.072 0 32 175 --

23 - 25 Very Stiff FAT CLAY 3 0.036 17.4 -- 750 0.006




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Depth(ft)

MaterialLPILE Soil Type

e CuK

Static e50

0 - 6 Stiff to Hard SANDY FAT CLAY 3 0.069 6.94 0 250 0.009

6 -18Medium Dense to

Dense CLAYEY SAND with GRAVEL

4 0.069 0 32 125 --

18 - 23Very Dense SILTY, CLAYEY SAND with

GRAVEL4 0.072 0 32 225 --

23 - 25 Very Dense CLAYEY GRAVEL with SAND 4 0.036 0 32 125 --




Drilled Shaft Construction Considerations

It is important to note that very hard clay dense to very dense clayey sand and clayey gravel was encountered in the boring locations. Thus, high-torque drilling equipment will likely be required for the drilled shaft construction. Additionally, sloughing may occur due to the presence of granular soils and ground water. The Contractor should be prepared for such conditions.

The Contractor should verify groundwater conditions before production drilled shaft installation begins. Comments pertaining to high-torque drilling equipment, groundwater, slurry, and temporary casing are based on conditions encountered at the locations of Borings B-1 to B-3. Conditions at individual drilled shaft locations may differ from those presented and may require that these issues be implemented to successfully install the shafts. Construction considerations for drilled shafts are outlined in the following table.

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Table 11: Drilled Shaft Installation Considerations

Recommended installation procedure USACE refers to FHWA(FHWA-NHI-10-016, May 2010)

High-torque drilling equipment anticipated Yes

Groundwater anticipated Yes

Temporary casing anticipated

Yes; extent depends upon subsurface soil and groundwater conditions encountered during

construction. Casing anticipated to be extended through water-bearing gravel, sand and clay soils;

and sufficiently into the underlying relatively impervious layer to achieve an adequate seal.

Please note that very stiff fat clay was encountered at 23 feet in Boring B-2. However,

this low permeability stratum was not encountered to the explored depths in B-1 and B-3. If

temporary casing is required, and an impermeable layer is not encountered to seal the casing,

Contractor may need to use slurry method for drilled shaft installation.

Slurry installation anticipatedYes, if casing is needed and a seal cannot be achieved in the relatively impervious layer as

noted above.

Concrete placement

Same day as drilling. If the excavation cannot be drilled and filled with concrete on the same day,

temporary casing or slurry may be needed to maintain an open excavation.

Maximum water accumulation in excavation 2 inches

Concrete installation method needed if water accumulates

Tremie or pump to displace water

Quality assurance monitoring

Geotechnical Engineer’s representative should be present during drilling of all shafts, should observe drilling and document the installed depth, should

confirm and document the bearing material type at the base of excavation and cleanliness of base, and should observe placement of steel rebars.

The following installation techniques will aid in successful construction of the drilled shafts:

The clear spacing between rebar or behind the rebar cage should be at least 3 times the maximum size of coarse aggregate.

Centralizers on the rebar cage should be installed to keep the cage properly positioned.

Cross-bracing of a reinforcing cage may be used when fabricating, transporting, and/or lifting. However, experience has shown that cross-bracing can contribute to the development of voids in a concrete shaft. Therefore, we recommend the removal of the cross-bracing prior to lowering the cage in the open shaft.

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The use of a tremie should be employed so that concrete is directed in a controlled manner down the center of the shaft to the shaft bottom. The concrete should not be allowed to ricochet off the pier reinforcing steel nor off the side walls.

The concrete should be designed to achieve the desired design strength when placed at a 7-inch slump, plus or minus 1-inch tolerance. Adding water to a mix designed for a lower slump does not meet these recommendations.

IBC Site Classification and Seismic Design CoefficientsSection 1613 of the International Building Code (2015) requires that every structure be designed and constructed to resist the effects of earthquake motions, with the seismic design category to be determined in accordance with Section 1613 or ASCE 7. Site classification using the International Building Code (2015) is based on the soil profile encountered to the 100-foot depth. The stratigraphy at the site location was explored to a maximum 25-foot depth.

The clays and granular soils having similar consistency were extrapolated to be present between 25 and 100-foot depths. Based on the site class definitions included in Table 1613.5.2 and 1613.5.5 of the 2015 Code and the encountered generalized stratigraphy, we characterize the site as Site Class D.

Seismic design coefficients were determined using the on-line software, Seismic Hazard Curves and Uniform Response Spectra, version 5.1.0, dated February 10, 2011 accessed at (http://earthquake.usgs.gov/hazards/designmaps/javacalc.php). Analyses were performed considering the 2015 International Building Code. Input included Site Coordinate (29.342639,-98.471292) and Site Class D. Seismic design parameters for the site are summarized in the following table.

Table 12: Seismic Design Parameters

Site Classification Fa Fv Ss S1

D 1.6 2.4 0.085g 0.029g

Where: Fa = Site coefficientFv = Site coefficientSs = Mapped spectral response acceleration for short periodsS1 = Mapped spectral response acceleration for a 1-second period

CONSTRUCTION CRITERIA

DrainageGood positive drainage during and after construction is very important to reduce soil volume changes that can detrimentally affect the performance of the planned monuments. Proper attention to surface and subsurface drainage details during the design and construction phase of development can aid in preventing many potential soil related problems during and following the completion of the project.

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Trench ExcavationsExcavations should comply with OSHA Standard 29CFR, Part 1926, Subpart P and all State of Texas and local requirements. A trench is defined as a narrow excavation in relation to its depth. In general, the depth is greater than the width, but the bottom width of the trench is not greater than 15 feet. Trenches greater than 5 feet in depth require a protective system such as trench shields, trench shoring, or sloping back the excavation side slopes.

GENERAL COMMENTS

This report was prepared as an instrument of service for this project exclusively for the use of Gonzalez De La Garza and the project design team. If the development plans change relative to layout or if different subsurface conditions are encountered during construction, we should be informed and retained to ascertain the impact of these changes on our recommendations. We cannot be responsible for the potential impact of these changes if we are not informed.Important information about this geotechnical report is provided in the ASFE publication included in Appendix F.

Geotechnical Design ReviewArias should be given the opportunity to review the design and construction documents. The purpose of this review is to check to see if our geotechnical recommendations are properly interpreted into the project plans and specifications. Please note that design review was notincluded in the authorized scope and additional fees may apply.

Subsurface VariationsSoil and groundwater conditions may vary away from the sample boring locations. Transition boundaries or contacts, noted on the boring logs to separate soil types, are approximate. Actual contacts may be gradual and vary at different locations. The Contractor should verify that similar conditions exist throughout the proposed area of excavation. If different subsurface conditions or highly variable subsurface conditions are encountered during construction, we should be contacted to evaluate the significance of the changed conditions relative to our recommendations.

Quality Assurance TestingThe long-term success of the project will be affected by the quality of materials used for construction and the adherence of the construction to the project plans and specifications. As Geotechnical Engineer of Record (GER), we should be engaged by the Owner to provide Quality Assurance (QA) testing. Our services will be to evaluate the degree to which constructors are achieving the specified conditions they’re contractually obligated to achieve, and observe that the encountered materials during earthwork for foundation installation are consistent with those encountered during this study. In the event that Arias is not retained to provide QA testing, we should be immediately contacted if differing subsurface conditions are encountered during construction. Differing materials may require modification to the

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recommendations that we provided herein. A message to the Owner with regard to the project QA is provided in the ASFE publication included in Appendix G.

Arias has an established in-house laboratory that meets the standards of the American Standard Testing Materials (ASTM) specifications of ASTM E-329 defining requirements for Inspection and Testing Agencies for soil, concrete, steel and bituminous materials as used in construction. We maintain soils, concrete, asphalt, and aggregate testing equipment to provide the testing needs required by the project specifications. All of our equipment is calibrated by an independent testing agency in accordance with the National Bureau of Standards. In addition, Arias is accredited by the American Association of State Highway & Transportation Officials (AASHTO), the United States Army Corps of Engineers (USACE) and the Texas Department of Transportation (TxDOT), and also maintains AASHTO Materials Reference Laboratory (AMRL) and Cement and Concrete Reference Laboratory (CCRL) proficiency sampling, assessments and inspections.

Furthermore, Arias employs a technical staff certified through the following agencies: the National Institute for Certification in Engineering Technologies (NICET), the American Concrete Institute (ACI), the American Welding Society (AWS), the Precast/Prestressed Concrete Institute (PCI), the Mine & Safety Health Administration (MSHA), the Texas Asphalt Pavement Association (TXAPA) and the Texas Board of Professional Engineers (TBPE). Our services are conducted under the guidance and direction of a Professional Engineer (P.E.) licensed to work in the State of Texas, as required by law.

Subgrade preparation and fill placement operations should be observed and tested by the Geotechnical Engineer or his/her representative. As a guideline, a minimum of 3 tests should be performed per lift. Any areas not meeting the required compaction should be recompacted and retested until compliance is met.

Standard of CareSubject to the limitations inherent in the agreed scope of services as to the degree of care and amount of time and expenses to be incurred, and subject to any other limitations contained in the agreement for this work, Arias has performed its services consistent with that level of care and skill ordinarily exercised by other professional engineers practicing in the same locale and under similar circumstances at the time the services were performed.

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Arias Geoprofessionals A-1 Arias Job No. 2016-426

APPENDIX A: FIGURES AND SITE PHOTOGRAPHS

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142 Chula Vista, San Antonio, Texas 78232Phone: (210) 308-5884 • Fax: (210) 308-5886

VICINITY MAPStinson Airport Monument Signage

San Antonio, Texas

Date: August 2, 2017 Job No.: 2016-426 Figure 11 of 1

Drawn By: RWL Checked By: GKApproved By: JS Scale: N.T.S.

Approximate Site Locations

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BORING LOCATION PLANStinson Airport Monument Signage

San Antonio, Texas

Date: August 2, 2017 Job No.: 2016-426REVISIONS: Drawn By: RWL Checked By: GKNo.: Date: Description: Approved By: SAH Scale: N.T.S.

Figure 21 of 1

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PORTION OF GEOLOGIC ATLAS OF TEXAS

(San Antonio Sheet)LEGEND

Symbol Name AgeQt Fluviatile Terrace Deposits Quaternary Period / HolooceneEwi Wilcox Group Tertiary Period / EoceneEmi Midway Group Tertiary Period / EoceneQle Leona Formation Quaternary Period / Pleitoscene

Fault Segment with Indication of Relative Movement


GEOLOGIC MAPStinson Monument Signage Design

San Antonio, Texas

Date: August 2, 2017 Job No.: 2016-426 Figure 31 of 1

Drawn By: RWL Checked By: GKApproved By: CMS Scale: N.T.S.

U D

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Arias Geoprofessionals B-1 Arias Job No. 2016-426

APPENDIX B: BORING LOGS AND KEY TO TERMS

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GW

GP

GM

GC

SW

SP

SM

SC

ML

CL

MH

CH

Massive or Weakly Bedded Limestones

Mor

e th

an h

alf o

f mat

eria

l SM

ALLE

R

than

No.

200

Sie

ve s

ize

FOR

MA

TIO

NA

L M

ATE

RIA

LS

GROUP SYMBOLS

KEY TO TERMS AND SYMBOLS USED ON BORING LOGS

CO

AR

SE-G

RA

INED

SO

ILS

GR

AVE

LSSA

ND

S

Mor

e th

an H

alf o

f Coa

rse

fract

ion

is

LAR

GER

than

No.

4 S

ieve

siz

e

Mor

e th

an h

alf o

f mat

eria

l LAR

GER

than

No.

200

Sie

ve s

ize

MAJOR DIVISIONS

Silty Gravels, Gravel-Sand-Silt Mixtures

Poorly-Graded Gravels, Gravel-Sand Mixtures, Little or no Fines

Well-Graded Gravels, Gravel-Sand Mixtures, Little or no Fines

DESCRIPTIONS

Clayey Sands, Sand-Clay Mixtures

Silty Sands, Sand-Silt Mixtures

Poorly-Graded Sands, Gravelly Sands, Little or no Fines

Well-Graded Sands, Gravelly Sands, Little or no FinesC

lean

Gra

vels

(li

ttle

or n

o Fi

nes)

Gra

vels

with

Fi

nes

(App

reci

able

am

ount

of F

ines

)

Cle

an S

ands

(li

ttle

or n

o Fi

nes)

Sand

s w

ith F

ines

(A

ppre

ciab

le

amou

nt o

f Fin

es)

Liqu

id L

imit

less

th

an 5

0Li

quid

Lim

it gr

eate

r tha

n 50

LIMESTONE

MARLSTONE

SANDSTONE

Clayey Gravels, Gravel-Sand-Clay Mixtures

Massive Sandstones, Sandstones with Gravel Clasts

Inorganic Clays of High Plasticity, Fat Clays

Inorganic Silts, Micaceous or Diatomaceous Fine Sand or Silty Soils, Elastic Silts

Inorganic Clays of Low to Medium Plasticity, Gravelly Clays, Sandy Clays, Silty Clays, Lean Clays

Inorganic Silts & Very Fine Sands, Rock Flour, Silty or Clayey Fine Sands or Clayey Silts with Slight Plasticity

Indurated Argillaceous Limestones

Indicates Final Observed Groundwater Level

Indicates Initial Observed Groundwater Location

Cretaceous Clay Deposits

Massive or Poorly Bedded Chalk Deposits

Mudstone or Massive Claystones

FIN

E-G

RA

INED

SO

ILS

Mor

e th

an h

alf o

f Coa

rse

fract

ion

is

SMAL

LER

than

No.

4 S

ieve

siz

e

SILT

S &

C

LAYS

SILT

S &

C

LAYS

GROUNDWATER

MARINE CLAYS

CHALK

CLAYSTONE

Very Dense

30 - 50

Over 50

10 - 30

Consistency and Strength of Cohesive Soils

Number of Blows per ft., N

Unconfined Compressive

Strength, qᵤ (tsf)Consistency

Density of Granular Soils

Relative Density

Very Loose

Number of Blows per ft.,

N0 - 4

4 - 10 Loose

Medium

Dense

Below 2

2 - 4 Soft

Very Soft

Stiff

Less than 0.25

0.25 - 0.5

0.5 - 1.0

1.0 - 2.0

Medium (Firm)

Very Stiff

Hard

4 - 8

8 - 15

15 - 30

Over 30 Over 4.0

2.0 - 4.0

SP

SW

Arias GeoprofessionalsITEM 2016-426

Group Symbol

GW(Less than 5% finesC )

Cu < 4 and/or GP[Cc < or Cc > 3]D

Gravels with Fines GM(More than 12% finesC )

GC

Sands Clean Sands SW(Less than 5% finesH ) Cu < 6 and/or SP

[Cc < or Cc > 3]D

Sands with Fines SM(More than 12% finesH )

SC

Silts and Clays inorganic CL

ML

organic OL

Silts and Clays inorganic CH

MH

organic OH

HIGHLY ORGANIC SOILS PTA Based on the material passing the 3-inch (75mm) sieveB If field sample contained cobbles or boulders, or both, add "with cobbles or boulders, or both" to group nameC Gravels with 5% to 12% fines require dual symbols:

GW-GM well-graded gravel with siltGW-GC well-graded gravel with clayGP-GM poorly-graded gravel with siltGP-GC poorly-graded gravel with clay

D Cu = D60/D10 Cc =

E If soil contains ≥ 15% sand, add "with sand" to group nameF If fines classify as CL-ML, use dual symbol GC-GM, or SC-SMG If fines are organic, add "with organic fines" to group nameH Sand with 5% to 12% fines require dual symbols:

SW-SM well-graded sand with siltSW-SC well-graded sand with claySP-SM poorly-graded sand with siltSP-SC poorly-graded sand with clay

I If soil contains ≥ 15% gravel, add "with gravel" to group nameJ If Atterberg limits plot in hatched area, soil is a CL-ML, silty clayK If soil contains 15% to < 30% plus No. 200, add "with sand" or "with gravel," whichever is predominantL If soil contains ≥ 30% plus No. 200, predominantly sand, add "sandy" to group nameM If soil contains ≥ 30% plus No. 200, predominantly gravel, add "gravelly" to group nameN PI ≥ 4 and plots on or above "A" lineO PI < 4 or plots below "A" lineP PI plots on or above "A" lineQ PI plots below "A" line

TERMINOLOGY

Boulders Over 12-inches (300mm) Parting Inclusion < 1/8-inch thick extending through samplesCobbles 12-inches to 3-inches (300mm to 75mm) Seam Inclusion 1/8-inch to 3-inches thick extending through sampleGravel 3-inches to No. 4 sieve (75mm to 4.75mm) Layer Inclusion > 3-inches thick extending through sampleSand No. 4 sieve to No. 200 sieve (4.75mm to 0.075mm)Silt or Clay Passing No. 200 sieve (0.075mm)Calcareous Containing appreciable quantities of calcium carbonate, generally nodular

Stratified Alternating layers of varying material or color with layers at least 6mm thickLaminated Alternating layers of varying material or color with the layers less than 6mm thickFissured Breaks along definite planes of fracture with little resistance to fracturingSlickensided Fracture planes appear polished or glossy sometimes striatedBlocky Cohesive soil that can be broken down into small angular lumps which resist further breakdownLensed Inclusion of small pockets of different soils, such as small lenses of sand scattered through a mass of clayHomogeneous Same color and appearance throughout

(D30)2

D10 x D60

KEY TO TERMS AND SYMBOLS USED ON BORING LOGSTABLE 1 Soil Classification Chart (ASTM D 2487-11)

Group NameB

Organic ClayK,L,M,N

Organi SiltK,L,M,O

Fat ClayK,L,M

Clayey GravelE,F,G

Well-Graded SandI

Poorly-Graded SandI

Silty SandF,G,I

Clayey SandF,G,I

Well-Graded GravelE

Poorly-Graded GravelE

Silty GravelE,F,G

Soil ClassificationCriteria of Assigning Group Symbols and Group Names Using Laboratory TestsA

More than 50% retained on No. 200 sieve

FINE-GRAINED SOILS

COARSE-GRAINED SOILS

Primarily organic matter, dark in color, and organic odor

Liquid limit less than 50

Liquid limit 50 or more

PI > 7 and plots on or above "A" lineJ

PI < 4 or plots below "A" lineJ

PI plots on or above "A" linePI plots on or below "A" line

Fines classify as CL or CH

(50% or more of coarse fraction passes No. 4 sieve)

50% or more passes the No. 200 sieve

Cu ≥ 4 and 1 ≤ Cc ≤ 3DGravels Clean Gravels

Elastic SiltK,L,M

Organic ClayK,L,M,P

Organic SiltK,L,M,Q

Peat

Lean ClayK,L,M

SiltK,L,M

Fines classify as CL or CH

Cu ≥ 6 and 1 ≤ Cc ≤ 3D

Fines classify as ML or MH

(More than 50% of coarse fraction retained on No. 4 sieve)

Fines classify as ML or MH

<0.75

<0.75

Liquid limit - oven driedLiquid limit - not dried

Liquid limit - oven driedLiquid limit - not dried

Arias GeoprofessionalsITEM 2016-426

Arias Geoprofessionals C-1 Arias Job No. 2016-426

APPENDIX C: FIELD AND LABORATORY EXPLORATION

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Arias Geoprofessionals C-2 Arias Job No. 2016-426

FIELD AND LABORATORY EXPLORATION

The field exploration program included drilling at selected locations within the site and intermittently sampling the encountered materials. The boreholes were drilled using single flight auger (ASTM D 1452). Samples of encountered materials were obtained using a split-barrel sampler while performing the Standard Penetration Test (ASTM D 1586), or using a thin-walled tube sampler (ASTM D 1587). The sample depth interval and type of sampler used is included on the soil boring log. Arias’ field representative visually logged each recovered sample and placed a portion of the recovered sampled into a plastic bag for transport to our laboratory.

SPT N values and blow counts for those intervals where the sampler could not be advanced for the required 18-inch penetration are shown on the soil boring log. If the test was terminated during the 6-inch seating interval or after 10 hammer blows were applied used and no advancement of the sampler was noted, the log denotes this condition as blow count during seating penetration.

Arias performed soil mechanics laboratory tests on selected samples to aid in soil classification and to determine engineering properties. Tests commonly used in geotechnical exploration, the method used to perform the test, and the column designations on the boring log where data are reported are summarized as follows:

Test Name Test Method Log DesignationWater (moisture) content of soil and rock by mass ASTM D 2216 WC

Liquid limit, plastic limit, and plasticity index of soils ASTM D 4318 PL, LL, PI

Amount of material in soils finer than the No. 200 sieve ASTM D 1140 -200

Unconfined Compressive Strength of Soil ASTM D 2166 Uc

The laboratory results are reported on the soil boring log.

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Arias Geoprofessionals D-1 Arias Job No. 2016-426

APPENDIX D: GRAIN SIZE DISTRIBUTION CURVES

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Arias Geoprofessionals E-1 Arias Job No. 2016-426

APPENDIX E: PLANS AND ELEVATIONS OF MONUMENT SIGNS

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Arias Geoprofessionals F-1 Arias Job No. 2016-426

APPENDIX F: ASFE INFORMATION – GEOTECHNICAL REPORT

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Arias Geoprofessionals G-1 Arias Job No. 2016-426

APPENDIX G: PROJECT QUALITY ASSURANCE

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8811 Colesville Road Suite G106 Silver Spring, Maryland 20910 Voice: 301.565.2733 Fax: 301.589.2017 E-mail: [email protected] Internet: www.asfe.org

PROJECT QUALITY ASSURANCE

1

Construction materials engineering and testing (CoMET) consultants perform quality-assurance (QA) services to evaluate the degree to which constructors are achieving

obligated to achieve. Done right, QA can save you time and money; prevent unanticipated-conditions claims, change orders, and disputes; and reduce short-term and long-term risks, especially by detecting molehills before they grow into mountains.

follow bad advice; e.g., “CoMET consultants are all the same. They all have accredited

standard QA scope of service, meaning that – must propose

the cheapest QA service it can live with, jeopardizing service quality and aggravating risk for the entire project team. Besides, the advice is based on misinformation.

Fact: , and the quality of those that are varies

important – nonetheless means that a facility

others just barely scrape by. And what an accrediting body typically evaluates – management, staff, facilities, and equipment – can change substantially before the next review, two, three, or more years from now.

Fact: Many have no

organizations of questionable merit, while not for

– want you to believe that price is the only

of course. Firms that sell low price typically lack the facilities, equipment, personnel, and

achieve the reliability concerned owners need to achieve quality in quality assurance.

A Message to Owners

Done right, QA can save you time and

money; prevent claims and disputes; and

reduce risks.

right because they follow bad advice.

are not accredited.

CoMET

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To derive maximum value from your

project manager to serve actively on the project team from beginning to end, a level

planning and design stages, experienced CoMET professionals can help the design

and establish appropriate observation, testing, and instrumentation procedures and protocols. They can also analyze plans and specs much as constructors do, looking for the little errors,

become the basis for big extras and big claims. They can provide guidance about operations that need closer review than others, because of their criticality or potential for error or abuse. They can also relate their experience with the various constructors that have expressed interest in your project.

services focus on two distinct issues: those that relate to geotechnical engineering and those that relate to the other elements of construction.

The geotechnical issues are critically important because they are essential to the “observational method” geotechnical

They apply the observational method by developing a sampling plan for a project, and

samples are properly obtained, packaged, and transported. The engineers review the samples and, typically, have them tested in their own laboratories. They use the information they

and develop preliminary recommendations

like excavations, site grading, foundation-bearing grades, and roadway and parking-lot preparation and surfacing.

their recommendations until they or

to verify that

the subsurface conditions the engineers

predicted are those that actually exist.

When unanticipated conditions are observed,

Responding to client requests, many

able to perform overall construction QA, encompassing – in addition to geotechnical issues – reinforced concrete, structural steel,

all CoMET consultants are alike, some owners take bids for the overall CoMET package,

someone other than the geotechnical engineer

Firms that sell low price typically lack the facilities, equipment, personnel,

concerned owners need to achieve quality in quality assurance.

To derive maximum value, require the project manager to

serve actively on the project team from beginning to end.

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3


a project site, to brief them on what to look for and where, when, and how to look. (

, because no one else

issues.) And once they arrive at a project site,

about what they observe, because they regard

operations is almost always penny-wise and pound-foolish. Still, because owners are given

explain why

To derive the biggest bang for the QA buck, identify three or even four quality-focused

available free at www.asfe.org.) Ask about

clients and client representatives involved;

Insist upon receiving

licenses, and insurance coverages.

Once you identify the two or three most

preferably at their own facility, so you can inspect their laboratory, speak with management and technical staff, and form an opinion about

manager participate in the meeting. You will

experienced personnel who are familiar with the codes and standards involved and know how to:

perform the necessary observation, inspection, and testing;

respond to the unexpected.

Important: Many of the services CoMET QA

operations and outcomes – require the good judgment afforded by extensive training and experience, especially in situations where standard operating procedures do not apply. You need to know who will be exercising that judgment: a 15-year “veteran” or a rookie?

on site to verify that the subsurface conditions they predicted are those that

actually exist.

the geotechnical engineer of record (GER)

always penny-wise and pound-foolish, helping to explain

why “geo” issues are the number-one source of construction-

industry claims and disputes.

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4


Also consider the tools CoMET personnel

calibration; others, less so. Passion is a good

not current, be cautious. You cannot trust test

about their reporting practices, including report

of nonconformance, and how they resolve complaints.

the constructor to pay for CoMET services. so you

fund QA via the constructor, have the CoMET fee included as an allowance in the bid documents. This arrangement ensures that you

prevents the CoMET fee from becoming part of

that the International Building Code (IBC) for Special Inspection

(SI) services commonly performed by the CoMET consultant as a service separate from

Because failure to comply could result in denial of an occupancy or use permit, having a contractual agreement that conforms to the IBC mandate is essential.)

constructor, have the CoMET fee included as

an allowance in the bid documents. Note,

too, that the International Building Code

(IBC) requires the owner to pay for Special

Inspection (SI) services.

CoMET consultants can usually quote their fees as unit fees, unit fees with estimated total (invoiced on a unit-fee basis), or lump-sum (invoiced on a percent-completion basis

which method is used, estimated quantities

their total-fee estimates by using quantities they know are too low and then request change orders long before QA is complete.

Once you and the CoMET consultant settle on the scope of service and fee, enter into a written

own contracts; most owners sign them. Some owners prefer to use different contracts, but that can be a mistake when the contract was prepared for construction services. Professional

Wholly avoidable problems occur when a contract includes

involved and fail to include those that do.

Many of the services

require good judgment.

is needed to deal promptly

with the unanticipated.

Some owners create wholly avoidable

problems by using a contract prepared for

construction services.

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8811 Colesville Road Suite G106 Silver Spring, Maryland 20910 Voice: 301.565.2733 Fax: 301.589.2017 E-mail: [email protected] Internet: www.asfe.org


QA for owners, not constructors. While constructors are commonly allowed to review QA reports as a courtesy, you need to make it clear that constructors do not have a legal right to rely on those reports; i.e., if constructors want to forgo their own observation and testing and rely on results derived from a scope created to meet only the needs of the owner, they

. In all too many cases where owners have not made that clear, some constructors have alleged that they did have a legal right to rely on QA reports and, as a result, the CoMET consultant – not they – are responsible for their failure to deliver what they contractually promised to provide. The outcome can be delays and disputes that entangle you and all other principal project

that possesses the resources and attitude needed to manage this and other risks as an element

early. Keep it engaged. And listen to what the CoMET consultant says. A good CoMET consultant can provide great value.

For more information, speak with your ASFE-Member CoMET consultant or contact ASFE directly.

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Documents

Division D Geotechnical Report - San Antonio