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Geotechnical Engineering ReportCreekside on Parmer

Harris Branch Tract E-33, Parmer Lane, West of Cameron RoadAustin, Texas

November 11, 2014Terracon Project No. 96145163

Prepared for:Austin HB Residential Properties, Ltd.

Austin, Texas

Prepared by:Terracon Consultants, Inc.

Austin, Texas

Terracon Consul tants, Inc . 5307 Industr ial Oaks Boulevard, Sui te 160 Aust in, Texas 78735 Regist rat ion No. F-3272P [512] 442 1122 F [512] 442 1181 terracon.com

November 11, 2014

Austin HB Residential Properties, Ltd.1010 Rio Grande, Suite BAustin, Texas 78701

Attention Mr. John McCulloughP: (512) 413-7099E: [email protected]

Regarding: Geotechnical Engineering ReportCreekside on ParmerHarris Branch Tract E-33, Parmer Lane, West of Cameron RoadAustin, TexasTerracon Project No. 96145163

Dear Mr. McCullough:

Terracon Consultants, Inc. (Terracon) is pleased to submit our Geotechnical Engineering Reportfor the Creekside on Parmer project to be located on East Parmer Lane near Cameron Road, inAustin, Texas. We trust that this report is responsive to your project needs. Please contact us ifyou have any questions or if we can be of further assistance.

We appreciate the opportunity to work with you on this project and look forward to providingadditional Geotechnical Engineering and Construction Materials Testing services in the future.

Copies Submitted: (1) Electroniccc: Charles E. Steinman, P.E. – CSF Civil Group, LLC ([email protected])

TABLE OF CONTENTS


PageEXECUTIVE SUMMARY ............................................................................................................ i1.0 INTRODUCTION ........................................................................................................... 12.0 PROJECT INFORMATION ............................................................................................ 1

2.1 Site Location and Description.............................................................................. 12.2 Project Description .............................................................................................. 22.3 Proposed Finished Floor Elevations and Grading ............................................... 2

3.0 SUBSURFACE CONDITIONS ....................................................................................... 33.1 Geology .............................................................................................................. 33.2 Typical Profile ..................................................................................................... 33.3 Swell Test Results .............................................................................................. 53.4 Groundwater ....................................................................................................... 6

4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION ..................................... 64.1 Geotechnical Considerations .............................................................................. 64.2 Earthwork............................................................................................................ 7

4.2.1 Compaction Requirements ...................................................................... 84.2.2 Grading and Drainage ............................................................................. 9

Interceptor Drains......................................................................104.2.3 Utility Trench Plugs ............................................................................... 11

4.3 Floor Slab Subgrade Preparation ...................................................................... 114.3.1 Additional Floor Slab Preparation In Cut Areas...................................... 14

4.4 Foundation System ........................................................................................... 144.4.1 Design Recommendations – Monolithic Slab-On-Grade ........................ 144.4.2 Foundation Construction Considerations ............................................... 17

Slab-on-Grade ..........................................................................17Foundation Construction Monitoring ..........................................18

4.5 Seismic Design Information .............................................................................. 184.6 Lateral Earth Pressures .................................................................................... 194.7 Pavements ........................................................................................................ 20

5.0 GENERAL COMMENTS .............................................................................................. 24APPENDIX A – FIELD EXPLORATION

Exhibit A-1 Site Location MapExhibit A-2 Boring Location PlanExhibit A-3 Boring Location AerialExhibit A-4 Field Exploration DescriptionExhibits A-5 through A-23 Boring Logs

APPENDIX B – LABORATORY TESTINGExhibit B-1 Laboratory TestingExhibits B-2 and B-3 ASTM D422 – Grain Size Distribution

APPENDIX C – SUPPORTING DOCUMENTSExhibit C-1 General NotesExhibit C-2 Unified Soil ClassificationsExhibit C-3 City of Austin MSWL Certification of Compliance

Geotechnical Engineering ReportCreekside on Parmer ■ Austin, TexasNovember 11, 2014 ■ Terracon Project No. 96145163


EXECUTIVE SUMMARY

A geotechnical investigation has been performed for the Creekside on Parmer multi-family projectto be located on Harris Branch Tract E-33 on East Parmer Lane near Cameron Road, in Austin,Texas. Subsurface conditions were evaluated using 17 borings drilled at the site.

Based on the information obtained from our subsurface exploration, the site can be developed forthe proposed project. The following geotechnical considerations were identified:

n Stripping should include surface vegetation, trees, loose topsoil, or other unsuitable materialssuch as organic matter, as well as the over-excavation required in the building areas.Proofrolling should be performed to detect weak areas. Weak areas such as subgradesexhibiting rutting and/or deflection should be removed and replaced with select fill or soilsexhibiting similar characteristics as the adjacent in-situ soils.

n Highly expansive clay soils (Strata I/II) were encountered in the borings. Structures supportedover these soils can experience higher than normal/tolerable shrink/swell movements.Subgrade preparation for grade-supported floor slab design is presented in Section 4.3 andis also discussed in Section 4.1.

n The proposed apartment buildings can be supported on monolithic slab-on-grade foundationsystems provided proper subgrade preparation is implemented. The slab and beamfoundations should be sized for a total load allowable bearing pressure of 2,500 psf or a netdead load allowable bearing pressure of 1,700 psf, if bearing in properly compacted select fillsoils.

n Pavements in parking areas should be designed with at least 2 inches of asphalt over 9 inchesof base material over moisture conditioned subgrade. As an alternative, 5 inches of reinforcedconcrete over moisture conditioned subgrade may be used.

n Pavements in light to medium duty traffic areas should be designed with at least 2.5 inches ofasphalt over 10 inches of base material over moisture conditioned subgrade. As analternative, 6 inches of reinforced concrete over moisture conditioned subgrade may be used.

n Close monitoring of the construction operations discussed herein will be critical in achievingthe design subgrade support. We therefore recommend that the Terracon be retained tomonitor this portion of the work.

This summary should be used in conjunction with the entire report for design purposes. It shouldbe recognized that details were not included or fully developed in this section, and the report mustbe read in its entirety for a comprehensive understanding of the items contained herein. Section5.0 – GENERAL COMMENTS should be read for an understanding of the report limitations.


GEOTECHNICAL ENGINEERING REPORTCREEKSIDE ON PARMER

HARRIS BRANCH TRACT E-33, PARMER LANE, WEST OF CAMERONROAD

AUSTIN, TEXASTerracon Project No. 96145163

November 11, 2014

1.0 INTRODUCTION

Terracon is pleased to submit our Geotechnical Engineering Report for the Creekside on Parmermulti-family project to be located on East Parmer Lane near Cameron Road, in Austin, Texas.This project was authorized by Mr. David Buicko, of Austin HB Residential Properties throughsignature of our “Agreement for Services” on August 12, 2014. The project scope was performedin general accordance with Terracon Proposal No. P96140933 dated July 31, 2014.

The purpose of this report is to describe the subsurface conditions observed at the borings drilledfor this project, analyze and evaluate the test data, and provide recommendations with respectto:

■ Foundation design and construction recommendations;■ Site, subgrade, and fill preparation;■ Lateral earth pressure and drainage for site retaining walls;■ Pavement design and construction; and■ Seismic site classification according to IBC 2012.

2.0 PROJECT INFORMATION

2.1 Site Location and Description

Item Description

Location The project site is an approximate 21.01-acre tract of land located on thesouth side of Parmer Lane, west of Cameron Road, in Austin, Texas.

Existing Improvements The site is unimproved.

Existing Ground CoverThe site is covered with variable vegetation. Much of the site containssignificant amounts of mesquite scrub/trees. There are more heavilywooded areas in the east and west portions of the site.


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Item Description

Existing TopographyWithin the proposed building areas, the site varies in elevation betweenapproximately 582 and 624 feet, sloping downhill to the south/easttowards the Harris Branch River.

2.2 Project Description

Item DescriptionSite layout See Exhibit A-2, Boring Location Plan, in Appendix A.

Proposed ImprovementsThe project will include the proposed construction of twelve (12) 3-storyand six (6) 2-story, multi-family apartment/townhome buildings, along withcovered parking, a clubhouse/pool and surface pavement areas.

Building Construction Anticipated to be wood frame construction. Monolithic slab and gradebeam foundation systems are assumed to be the foundation of choice.

Maximum Column Loads Unknown; typical light frame loading assumed.Cut and Fill Slopes Some cut and fill slopes are anticipated.Free-standing RetainingWalls Miscellaneous walls up to 6-8 feet in height assumed.

Below-Grade Areas Not anticipated.

2.3 Proposed Finished Floor Elevations and Grading

FLOOR SLAB GRADING

Building FFE (feet) Approximate Cut(feet) Approximate Fill (feet)

Building 1 615.1 About 1 to 4½ -Building 2 613.9 Up to about 1 Up to about 2Building 3 611.0 Up to about 3½ Up to about 4Building 4 610.3 6 to 7½ -Building 5 620.1 Up to about 2¾ Up to about 1Building 6 617.2 About 2 to 9 -Building 7 599.0 to 609.7 Up to about 10 Up to about 2¾Building 8 597.8 Up to about 1 Up to about 3½Building 9 589.2 to 599.9 About ½ to 7½ Up to about 5½

Building 10 587.2 to 597.9 About 1 to 3½ Up to about 7Building 11 596.9 About 3½ to 8 -Building 12 585.0 to 595.7 About ½ to 6½ Up to about 8½Building 13 593.7 Up to about 1 Up to about 3¼



Building FFE (feet) Approximate Cut(feet) Approximate Fill (feet)

Building 14 583.6 to 594.3 Up to about 3 About 1½ to 10½Building 15 592.0 - About 2½ to 7Building 16 589.7 - About 3½ to 7½Building 17 591.2 About 1 to 3½ -Building 18 590.9 Up to about 1 -

Building19/Clubhouse 620.7 About 2½ to 4 -

3.0 SUBSURFACE CONDITIONS

3.1 Geology

Based on our review of available geologic information1 and the samples obtained from the testborings, the study area appears to lie within an area characterized by the Taylor Group clay ofUpper Cretaceous Age. The Taylor Group generally consists of highly plastic expansive clay soilsranging in color from tan to dark gray.

3.2 Typical Profile

Based on the results of the borings, subsurface conditions on the project can be generalized asbelow.

Description

ApproximateDepth Rangeof Stratum,

feet

Material Encountered Soil Consistency /Soil Density

Stratum I 0 to 6 Fat Clay (CH) to Lean Clay (CL) – DarkBrown to Grayish-Brown Stiff to Hard

Stratum II 1 to >20Fat Clay (CH) to Lean Clay (CL) to Lean Clay

with Sand (CL) – Light Brown to Tan toGrayish-Brown to Yellowish-Brown

Very Stiff to Hard

The Stratum I dark brown to grayish-brown soils encountered in the borings generally exhibited avery high shrink/swell potential as indicated by the following measured liquid limits, plastic limits,and fines contents (percent passing the No. 200 sieve):

1 Garner, L.E. and Young, K.P., “Environmental Geology of the Austin Area: An Aid to Urban Planning”,Bureau of Economic Geology, The University of Texas at Austin, 1976.



SampleLocation Depth (feet) Liquid Limit

(%)Plastic Limit

(%)Plasticity Index

(%)Fines(%)

Boring B-2 2 – 4 57 15 42 -Boring B-4 2 – 4 41 25 16 -Boring B-5 2 – 4 47 16 31 -Boring B-7 0 – 2 61 18 43 62Boring B-9 0 – 2 67 15 52 -

Boring B-11 0 – 2 70 18 52 -Boring B-13 2 – 4 69 16 53 95Boring B-15 2 – 4 79 19 60 -Boring B-16 2 – 4 79 18 61 -Boring B-19 0 – 2 66 16 50 -

Average - 64 18 46 -

The in-situ moisture content of the Stratum I soils ranged from 16 percent dry of, to 10 percentwet of corresponding plastic limits. The measured values of unconfined compressive strength ofthe Stratum I fat clay soils were found to vary from approximately 2.7 to 12 tons per square foot(tsf) (average ~6.2 tsf). Hand penetrometer (HP) readings on the Stratum I soils were found tovary from 1.75 to over 4.5 tsf. Generally, the Stratum I soils was visually observed to besignificantly darker in color than the Stratum II soils.

The Stratum II light brown to tan to grayish-brown to yellowish-brown soils encountered in theborings generally exhibited a very high shrink/swell potential as indicated by the followingmeasured liquid limits, plastic limits, and fines contents:


(%)Plastic Limit

(%)Plasticity Index

(%)Fines(%)

Boring B-1 2 – 4 34 14 20 82Boring B-1 6 – 8 36 14 22 -Boring B-3 4 – 6 58 15 43 93Boring B-3 8 – 10 54 16 38 -Boring B-4 4 – 6 35 16 19 60Boring B-4 8 – 10 39 15 24 -Boring B-5 6 – 8 42 15 27 71Boring B-6 2 – 4 63 16 47 -Boring B-6 6 – 8 75 22 53 -Boring B-7 6 – 8 79 22 57 -Boring B-8 2 – 4 58 16 42 -




(%)Plastic Limit

(%)Plasticity Index

(%)Fines(%)

Boring B-8 8 – 10 72 20 52 -Boring B-9 8 – 10 78 22 56 -

Boring B-10 2 – 4 61 18 43 -Boring B-10 8 – 10 79 22 57 -Boring B-11 6 – 8 69 19 50 99Boring B-12 4 – 6 85 23 62 -Boring B-12 8 – 10 73 23 50 -Boring B-13 6 – 8 76 19 57 -Boring B-14 2 – 4 76 18 58 -Boring B-14 6 – 8 75 20 55 -Boring B-15 8 – 10 56 13 43 -Boring B-16 8 – 10 84 21 63 98Boring B-17 4 – 6 75 18 57 -Boring B-17 8 – 10 89 20 69 -

Average - 65 18 47 -

The in-situ moisture content of the Stratum II soils ranged from 10 percent dry of, to 8 percent wetof corresponding plastic limits. The measured values of unconfined compressive strength of theStratum I fat clay soils were found to vary from approximately 4 to 15 tsf (average ~9.5 tsf). Handpenetrometer (HP) readings on the Stratum II soils were found to vary from 1.75 to over 4.5 tsf.

Conditions encountered at the boring locations are indicated on each individual boring log.Stratification boundaries on the boring logs represent the approximate location of changes insubsurface material types; in-situ, the transition between materials may be gradual. Details for theborings can be found on the boring logs on Exhibits A-5 through A-23 of Appendix A.

3.3 Swell Test Results

Six free swell tests were performed on soil samples and the results are presented in the followingtable. After surcharge pressures were applied that represent the approximate in-situ overburdenpressure, the sample was inundated with water for about 72 hours while measurements of verticaldisplacement were taken. The magnitude of swell is recorded as a function of the change inthickness during the test in relation to the thickness of the sample loaded to its overburdenpressure.



BoringNo.

Approx.Sample

Depth, ft.

ConfiningPressure

(psf)Stratum Initial

Moisture, %Final

Moisture, % Free Swell, %

B-3 6 to 8 840 II 16 26 6.0B-8 8 to 10 1,080 II 20 27 6.2

B-10 6 to 8 840 II 24 29 6.0B-12 4 to 6 600 II 26 31 5.9B-14 4 to 6 600 II 22 27 5.6B-17 6 to 8 840 II 23 29 5.7

Based on our laboratory results, the samples tested generally exhibit a very high swell potential.

3.4 Groundwater

The borings were dry augered to depths of about 5 to 20 feet below existing grade. Groundwaterwas not observed during dry augering.

Although not observed, groundwater at the site should be anticipated in more perviousseams/fissures of the subgrade soils and/or in “perched” areas immediately above less permeableseams/layers of the subsurface soils. During periods of wet weather, zones of seepage mayappear and isolated zones of “perched water” may become trapped (or confined) by zonespossessing a low permeability. Please note that it often takes several hours/days for water toaccumulate in a borehole, and geotechnical borings are relatively fast, short-term boreholes thatare backfilled the same day. Long-term groundwater readings can more accurately be achievedusing monitoring wells. Please contact us if this is desired. Groundwater conditions should beevaluated just prior to construction.

4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION

The following recommendations are based upon the data obtained in our field and laboratoryprograms, project information provided to us, and on our experience with similar subsurface andsite conditions.

4.1 Geotechnical Considerations

We understand that the project is to consist of the construction of twelve (12) 3-story and six (6)2-story, multi-family apartment/townhome buildings, along with covered parking, a clubhouse/pooland surface pavement areas with proposed FFE’s and grading detailed in Section 2.3. In additionto the proposed apartment buildings, a water quality pond and adjacent pavements will also be



constructed. If any of the above information is incorrect, Terracon should be notified to review andmodify and/or verify recommendations in writing.

Based on our test borings, expansive soils (both Strata I and II) that exhibit a very high potentialfor volumetric change during moisture variations are present at the site. Free swell test results,as discussed in Section 3.3 – Swell Test Results were found to range from about 5.6 and 6.2percent for the Stratum I and II soils. The soils exhibit a Potential Vertical Rise (PVR) of up toabout 6¾ inches as estimated by the Texas Department of Transportation (TxDOT) Method TEX-124-E, if present in a dry condition.

This report provides recommendations to help mitigate the effects of soil shrinkage andexpansion. However, even if these procedures are followed, some movement and cracking in thestructures should be anticipated. The severity of cracking and other damage such as uneven floorslabs will probably increase if any modification of the site results in excessive wetting or drying ofthe expansive soils. Eliminating the risk of movement and distress may not be feasible, but it maybe possible to further reduce the risk of movement if significantly more expensive measures (suchas drilled piers and suspended floor slabs) are used during construction. We would be pleased todiscuss other construction alternatives with you upon request.

Based on the subsurface conditions observed at the site, it is our opinion that monolithic slab-on-grade foundation systems would be appropriate to support the proposed multi-family apartmentbuildings and leasing office provided the subgrade for the buildings are prepared to reduce theshrink/swell potential of the subgrade to more tolerable levels. Recommendations for this type offoundation system are presented in the following subsections along with other geotechnicalengineering considerations for this project.

4.2 Earthwork

Construction areas should be stripped of vegetation, topsoil, and other unsuitable materials.Roots of trees to be removed within construction areas should be grubbed to full depths, includingthe dry soil around the roots.

Once final subgrade elevations have been achieved (including the over-excavation required forbuilding pads), the exposed subgrade, should be carefully and thoroughly proofrolled with a 20-ton pneumatic roller or a fully-loaded dump truck to detect weak zones in the subgrade. Weakareas detected during proofrolling, as well as zones containing debris or organics, and voidsresulting from removal of tree roots, etc., should be removed and replaced with soils exhibitingsimilar classification, moisture content, and density as the adjacent in-situ soils. Proper sitedrainage should be maintained during construction so that ponding of surface runoff does notoccur and causes construction delays and/or inhibit site access.



Subsequent to proofrolling, and just prior to placement of fill, the exposed subgrade within theconstruction areas should be evaluated for moisture and density. If the moisture and/or densityrequirements do not meet the criteria described in the table below, the subgrade should bescarified to a minimum depth of 6 inches, moisture adjusted and compacted to at least 95 percentof the Standard Proctor (ASTM D 698) maximum dry density.

Select fill and on-site soils should meet the following criteria.

Fill Type 1 USCS Classification Acceptable Location For Placement

ImportedSelect Fill 2,3

CL, SC, and/or GC(10≤PI≤20)

Select fill material should be used for all gradeadjustments within the building limits.

General Fill 4 CL, CH, GC General fill is for use within other non-structural areasof the site. If imported, paving fill should have a PI≤35.

1. Prior to any filling operations, samples of proposed borrow and/or on-site materials should beobtained for laboratory testing. The tests will provide a basis for evaluation of fill compaction by in-place density testing. A qualified soil technician should perform sufficient in-place density tests duringthe filling operations to evaluate that proper levels of compaction, including dry unit weight andmoisture content, are being attained.

2. Imported select fill should consist of crushed limestone base material meeting the requirements ofthe Texas Department of Transportation (TxDOT) 2004 Standard Specifications Item 247, Type A,Grade 3, or a low-plasticity coarse-grained soil with a plasticity index between 10 and 20 percent, amaximum gravel content (percentage retained on No. 4 sieve) of 40 percent, and rocks no larger than4 inches in their largest dimension. As an alternative, a low-plasticity granular fill material which doesnot meet these specifications may be used only if approved by Terracon.

3. Based on the laboratory testing performed during this exploration, the on-site Stratum I/II soils arenot suitable for re-use as select fill. Portions of the Stratum I/II lean clay soils may be suitable for re-use as select fill if the PI is less than 20; however, before the final determination can be made as towhether or not the material is acceptable, the excavated material should be separated from organicsand debris and stockpiled for further laboratory testing in order to confirm its suitability for re-use asselect fill.

4. Excavated on-site soils, if free of organics, debris, and rocks larger than 4 inches, may be consideredfor use as fill in pavement, landscape, or other general areas. For economic reasons, expansive soilsare often used in pavement and/or flatwork areas. The owner should be aware that the risk exists forfuture movements of the subgrade soils which may result in movement and/or cracking of pavementsand/or flatwork.

4.2.1 Compaction RequirementsRecommended compaction and moisture content criteria for engineered fill materials are asfollows:



BENEATH FOUNDATIONS, SLAB, AND ALL ASSOCIATED FLATWORK AREAS DEFINEDAS BUILDING AREA LIMITS

Material Type and Location

Per the Standard Proctor Test (ASTM D 698)

MinimumCompaction

Requirement (%)

Range of Moisture Contents forCompaction

Minimum MaximumCrushed Limestone Base / Imported Select

Fill95 1 -3% +3%

Building Subgrade and Moisture ConditionedBuilding Pad Fills 93 +2% +6%

1. For fills greater than 5 feet in depth, the compaction should be increased to at least 100 percent ofthe ASTM D 698 maximum dry density.

BENEATH PAVEMENTS AND OTHER NON-STRUCTURAL AREAS OF THE SITE

Material Type and Location

Per the Standard Proctor Test (ASTM D 698)

MinimumCompaction

Requirement (%)

Range of Moisture Contents forCompaction

Minimum Maximum

Paving Fill with PI ≤ 20 95 -3% +3%

Paving Fill with PI > 20 and Subgrade 95 Optimum +4%

Crushed Limestone Base (beneathpavements) 95 1 -3% +3%

1. Per the Modified Proctor Test (ASTM D 1557).

Engineered fill materials should be placed in horizontal, loose lifts not exceeding 8 inches inthickness and should be thoroughly compacted. Where light compaction equipment is used, as iscustomary within a few feet of retaining walls and in utility trenches, the lift thickness may need tobe reduced to achieve the desired degree of compaction.

We recommend that engineered fill be tested for moisture content and compaction duringplacement. Should the results of the in-place density tests indicate the specified moisture orcompaction limits have not been met, the area represented by the test should be reworked andretested as required until the specified moisture and compaction requirements are achieved.

4.2.2 Grading and DrainageThe performance of the foundation systems for the proposed apartment buildings will not only bedependent upon the quality of construction, but also upon the stability of the moisture content ofthe near-surface soils. Therefore, we highly recommend that site drainage be developed so thatponding of surface runoff near the structures does not occur. Accumulation of water near the



structure’s foundations may cause significant moisture variations in the soils adjacent to thefoundations, thus increasing the potential for structural distress.

Positive drainage away from the structures must be provided during construction and maintainedthrough the life of the proposed project. Infiltration of water into excavations should be preventedduring construction. It is important that foundation soils are not allowed to become wetted. Allgrades must provide effective drainage away from the structures during and after construction.The easiest way to achieve this would be to provide concrete aprons around the exterior perimeterof the buildings for a distance of at least 6 feet (about 1 foot wider than the select fill pad overbuild).The concrete should be sloped to provide drainage away from the buildings and all joints shouldbe sealed, particularly those directly abutting the buildings. In lieu of providing concrete apronsand if sloping unpaved ground is planned around the buildings, then the select fill overbuild(recommended 5 feet beyond building limits) should be excavated to a depth of at least 2 feetbelow final grades, removed and replaced with a minimum of 2 feet of moisture conditioned andcompacted Stratum I/II fat clay soils. The Stratum I/II fat clay soils should be compacted andmoisture conditioned per Section 4.2.1. This procedure is recommended to reduce the possibilityof surface runoff infiltrating into the more pervious select fill soils and ponding below the proposedbuilding. We would be glad to discuss other measures (e.g. horizontal or vertical barriers) toreduce moisture infiltration in unpaved areas, if desired. Exposed (unpaved) ground should besloped at a minimum 5 percent away from each building for at least 10 feet beyond the perimeterof each building.

Roof runoff and surface drainage should be collected and discharged away from the structures toprevent wetting of the foundation soils. Roof gutters should be installed and connected todownspouts and pipes directing roof runoff at least 10 feet away from the structures, or dischargedon to positively sloped pavements.

If irrigation is planned, sprinkler mains and spray heads should preferably be located at least 5feet away from the structures such that they cannot become a potential point source of waterdirectly adjacent to the structures. In addition, the owner and/or builder should be made awarethat placing large bushes and trees adjacent to the structures may cause significant moisturevariations in the soils underlying the structures. In general, tree roots can adversely influence thesubsurface soil moisture content to a distance of 1 to 1½ times the mature height of the tree andbeyond the tree canopy. Watering of vegetation should be performed in a timely and controlledmanner and prolonged watering should be avoided. Landscaped irrigation adjacent to thefoundation units should be minimized or eliminated. Special care should be taken such thatunderground utilities do not develop leaks with time.

Interceptor DrainsIn conjunction with the building pad preparation discussed in Section 4.3 – Floor Slab SubgradePreparation, we suggest that, in an effort to reduce the amount of water possibly flowing into thesubgrade of the buildings, interceptor (French) drains be installed just up gradient from the



buildings, particularly in the areas with proposed cuts. The drains should consist of gravel-packedtrenches (gravel meeting ASTM C33, Grade 57 or 67) wrapped in filter fabric (Mirafi 140N orsimilar) with an embedded perforated PVC pipe (minimum 4-inch diameter) to collect any water.The trench drain should be sloped at a minimum 1% to gravity drain toward an appropriate outletor storm sewer pipe. The trench drain should be a minimum of 12 inches wide and 36 inchesdeep, but should extend deeper than the bottom of the select fill building pad.

4.2.3 Utility Trench PlugsUtility trenches are a common source of water infiltration and migration. All utility trenches thatpenetrate beneath the buildings should be effectively sealed to restrict water intrusion and flowthrough the trenches that could migrate below the buildings. We recommend constructing aneffective clay or flowable fill “trench plug” that extends at least 2 feet out from the face of thebuilding exterior. The clay fill/flowable fill should be placed to completely surround the utility lineand it should fill the utility trench completely in width and height, with the exception of topsoil atthe surface. If clay plug is used, it should be fat clay with a minimum PI of 30 and should becompacted in accordance with recommendations in Section 4.2.1. If flowable fill is used, it shouldbe in accordance with TxDOT Item 401.

4.3 Floor Slab Subgrade Preparation

As mentioned previously, the soils at this site exhibit a PVR of up to about 6¾ inches. A commonmethod of subgrade preparation to reduce potential expansion of the subgrade would be toprovide a pad of properly placed and compacted select fill, in conjunction with moistureconditioned clays, beneath the floor slabs. The corresponding decrease in the potential soilmovement is primarily a function of the fill pad thickness and the moisture levels of the underlyingclay subgrade. While the indicated preparations do not eliminate the potential for soil movement,the magnitude of such movements may be reduced to more conventional and acceptable levels.

Based on the proposed site grading plan provided to us, the FFE’s for the proposed multi-familyapartment buildings are summarized in Section 2.3, along with our interpretation of theapproximate cut/fill requirements. If any of this information is incorrect, Terracon should be notifiedto review and modify and/or verify recommendations in writing.

For the proposed apartment buildings, we recommend that the near-surface soils be prepared asstated below to reduce the potential for foundation movements associated with volumetricchanges of the underlying clay soils due to moisture variation. Typically, the subgrade within thebuilding areas are prepared to reduce the maximum estimated PVR to about one inch or less.The subgrade preparation options presented below should reduce post-construction floor slabmovements to about one inch. If a 1½-inch PVR design is desired, the indicated thickness ofselect fill may be decreased by 1-foot. The level of subgrade preparation should be based on theperformance desired by the owner, taking into consideration the effects which foundationmovements could have upon the structures.



In several cases, much of the select fill is the above-grade filling that would be required regardless.

BUILDINGS 1, 2, 3, 4, 7, 8, 9, 10, 11, 12, 13, 14

ComponentMinimum Material Thickness (feet) 1

Option 1 Option 2 Option 3Select Fill 7½ 6½ 5½

Moisture Conditioned Subgrade 2 4 6

Minimum Total Thickness 9½ 10½ 11½1. To achieve a PVR of 1½ inches, the indicated thickness of select fill may be reduced by 1-foot.

BUILDING 5 & 19 (CLUBHOUSE)


Option 4 Option 5 Option 6Select Fill 4 3 2

Moisture Conditioned Subgrade 1 2½ 4

Minimum Total Thickness 5 5½ 61. To achieve a PVR of 1½ inches, the indicated thickness of select fill may be reduced by 1-foot.

BUILDINGS 6 & 17


Option 7 Option 8 Option 9Select Fill 6½ 5½ 4½


Minimum Total Thickness 8½ 9½ 10½1. To achieve a PVR of 1½ inches, the indicated thickness of select fill may be reduced by 1-foot.

BUILDINGS 15, 16 & 18


Option 10 Option 11 Option 12Select Fill 8 7 6


Minimum Total Thickness 10 11 12

1. To achieve a PVR of 1½ inches, the indicated thickness of select fill may be reduced by 1-foot.

With each alternative, the indicated thickness of moisture conditioned subgrade soils afterremoval of on-site soils should be moisture conditioned to between +2 and +6 percent of optimummoisture content and compacted to ≥93 percent of the Standard Proctor (ASTM D 698) maximumdry density. Upon completion of moisture conditioning and compacting of exposed soils, properlycompacted select fill should be placed and compacted within the building areas as indicated inthe tables above for the selected options. No less than the above indicated thickness of select



fill soil should be provided in the building pad areas. With these preparation options, post-construction floor slab movements should be on the order of about 1-inch. Due to themultiple options, we suggest that the option performed under each building be noted onthe final as-built set of plans for final documentation purposes.

Water added to the clays in the moisture conditioning process may need to soak into the soils atleast overnight prior to compaction to achieve a uniform moisture level within the clay soils. Theclay soils may become difficult to handle and compact and may present construction equipmentaccess difficulties at the moisture levels described above. The contractor should also provideappropriate equipment to achieve the proper level of compaction at the moisture levels indicatedabove. This should reduce the swell potential of these soils, in addition to reducing theirpermeability, which should help to protect the underlying clay subgrade from changes in moisturecontent.

Prior to moisture conditioning of the subgrade, it should be thoroughly proofrolled with a 20-tonroller to detect weak zones in the subgrade as discussed in Section 4.2 – Earthwork. Then, priorto placement and compaction of select fill, the soil subgrade should be scarified, moistureadjusted, and compacted as given above. All fill material placed within the building footprintshould meet the requirements of Select Fill described in Section 4.2 – Earthwork. The abovesubgrade preparation recommendations should be applied to an area extending a minimum of 5feet outside of building and canopy areas, including attached walkways, ramps, swimming poolareas, pool decks, garages, and any other architectural members. Material and placementrequirements for select fill, as well as other subgrade preparation recommendations, arepresented in Section 4.2 – Earthwork. We suggest the use of crushed limestone base as theselect fill material within the upper 6 inches of the fill pad from a standpoint of construction accessduring wet weather, as well as from a standpoint of floor slab support.

Flatwork will be subject to post-construction movements also. For any flatwork (sidewalks, ramps,etc.) outside of the building areas which will be sensitive to movement, subgrade preparation asdiscussed above should be considered to reduce differential movements between the flatworkand the adjacent building. If subgrade preparation as given above for building areas is notimplemented in the exterior flatwork areas, those areas may be susceptible to post-constructionmovements (up to about 6¾ inches) as discussed above for in-situ soil conditions.

We should also note that the potential movement values indicated are based upon moisturevariations in the subgrade due to circumstances such as moisture increases due to rainfall andloss of evapotranspiration. In circumstances where significant water infiltration beneath the floorslab occurs (such as a leaking utility line or water seepage from outside the building resulting frompoor drainage), movements in isolated floor slab areas could potentially be in excess of thoseindicated in this report.



4.3.1 Additional Floor Slab Preparation In Cut AreasAs discussed in Section 2.3, cuts of up to about 10 feet into the Stratum II fat clays are anticipated.This material has the potential to, and commonly does, swell significantly upon exposure to theelements. The combination of releasing the overburden pressure by removal of the overlying soils,and exposing it to possible moisture variations due to exposure to the elements, are the twoprimary factors attributed to this formation heaving. Therefore, we recommend that in all buildingareas with 5 or more feet of planned cuts, that two (2) extra feet of Stratum II soils be moistureconditioned, in addition to the indicated thicknesses of moisture conditioned subgrade soilspresented in Section 4.3 prior to placing select fill.

For example, according to the proposed site grading plan, the north-western portion of the south-east half of Building 7 will require cuts of up to about 10 feet. Therefore, if floor slab subgradepreparation Option 1 is chosen, than the subgrade preparation should consist of 7½ feet of selectfill overlying 4 feet of moisture conditioned Stratum II soils.

4.4 Foundation System

As mentioned in Section 4.1 – Geotechnical Considerations, it is our opinion that monolithicslab-on-grade foundation systems would be appropriate to support the proposed multi-familyapartment buildings provided the subgrade for the buildings are prepared to reduce theshrink/swell potential of the subgrade to more tolerable levels. Recommendations for this type offoundation system are presented in the following subsections along with other geotechnicalengineering considerations for this project.

4.4.1 Design Recommendations – Monolithic Slab-On-GradeA monolithic slab-on-grade foundation system (either conventionally reinforced or post-tensioned)would be appropriate to support the multi-family apartment buildings provided subgradepreparation as described in Section 4.3 – Floor Slab Subgrade Preparation is followed.

The slab foundation design parameters presented in the following tables are based on the criteriapublished by the Building Research Advisory Board (BRAB), the Prestressed Concrete Institute(PCI), the Wire Reinforcement Institute (WRI), and the Post-Tensioning Institute (PTI) 3rd Edition.These are essentially empirical design methods and the recommended design parameters arebased on our understanding of the proposed project, our interpretation of the information and datacollected as a part of this study, our area experience, and the criteria published in the BRAB, PCI,WRI, and PTI design manuals.

Conventional Slab and Beam System Parameters for Subgrade Prepared as in Section 4.3Minimum embedment of grade beams below finalgrade1 24 inches

Bearing Pressures (allowable) 2 Net dead plus sustained live load – 1,700 psf



Conventional Slab and Beam System Parameters for Subgrade Prepared as in Section 4.3Net total load – 2,500 psf

Subgrade Modulus (k) 3 150 pci if on crushed limestone base100 pci if on alternative select fill

Approximate Potential Vertical Rise (PVR) About 1-inch 4

1. Embedment is to reduce surface water migration below the foundation elements and to develop properend bearing and is not based on structural considerations. The grade beam width and depth should beproperly evaluated by the structural engineer. Grade beams may be thickened and widened at interiorcolumn locations to serve as spread footings at these concentrated load areas.

2. Grade beams may bear on properly compacted imported select fill soils.3. Several design methods use the modulus of subgrade reaction, k, to account for soil properties in design

of flat, floor slabs. The modulus of subgrade reaction is a spring constant that depends on the kind ofsoil, the degree of compaction, and the moisture content. Based on our recommendations provided inSection 4.3, the above indicated subgrade modulus can be used for design of a flat, grade-supportedfloor slab.

4. Differential movements may result from variances in subsurface conditions, loading conditions andconstruction procedures. We recommend that measures be taken whenever practical to increase thetolerance of the building to post-construction foundation movements. An example of such measureswould be to provide frequent control joints for exterior masonry veneers and interior sheetrock walls(particularly near doors and windows) to control cracking across such walls and concentrate movementalong the joints.

BRAB/WRI/PCI Parameters for Subgrade Prepared as in Section 4.3

Design PlasticityIndex (PI) 1, 2

Buildings 1, 2, 3, 4, 7, 8, 9, 10, 11, 12,13, 14

1-inch PVR Option 351½-inch PVR Option 41

Building 5 & 19 (Clubhouse)1-inch PVR Option 301½-inch PVR Option 32

Building 6 & 171-inch PVR Option 361½-inch PVR Option 39

Buildings 15, 16 & 181-inch PVR Option 471½-inch PVR Option 50

Climatic Rating (Cw) 17Unconfined Compressive Strength 2 1.0 tsf

Soil Support Index(C) for BRAB 2

Buildings 1, 2, 3, 4, 7, 8, 9, 10, 11, 12,13, 14

1-inch PVR Option 0.791½-inch PVR Option 0.72

Building 5 & 19 (Clubhouse)1-inch PVR Option 0.841½-inch PVR Option 0.82

Building 6 & 171-inch PVR Option 0.781½-inch PVR Option 0.74



BRAB/WRI/PCI Parameters for Subgrade Prepared as in Section 4.3

Buildings 15, 16 & 181-inch PVR Option 0.661½-inch PVR Option 0.63

1. The BRAB effective PI is equal to the near surface PI if that PI is greater than all of the PI values in theupper 15 feet; otherwise it is the weighted average of the PI values in the upper 15 feet. The WRI/PCIeffective PI is always the weighted average of the PI values in the upper 15 feet.

2. For subgrade prepared as in Section 4.3.

Post Tensioning Institute (PTI) Parameters for Subgrade Prepared as in Section 4.3 1

Depth of Seasonal Moisture Change 2 Up to 15 feet

Plasticity Index 3

Select fill – 15Stratum I soils – 16 to 61Stratum II soils – 19 to 69

Percent Finer than 2 Microns (estimated) 3 Select fill – 25Stratum I/II soils – 40 to 80

Soil Fabric Factor 1.0Approximate Thornthwaite Moisture Index -12Estimated Constant Soil Suction 3.5 pFRange of Soil Suction 3.0 to 4.5 pF1. Based on our analysis of the field and laboratory data, design parameters were computed using the

Addendum to the 2004 Post-Tensioning Institute (PTI) method2 for slab-on-grade design and thesubsequent Errata to the Addendum approved by the PTI Slab-on-Grade Committee on February 7,2008.

2. The moisture beneath a shallow foundation will change in response to wetting and drying conditionsaround the foundation perimeter. The moisture condition has a significant effect on slab behavior and ishighly variable with time, changing seasonally, with annual climate conditions, drainage patterns, groundcover, and vegetation (trees and shrubs).

3. The plasticity index and the clay mineral percentage are values of the soil that can be estimated bylaboratory tests, and, although variable from location to location, remain relatively constant with time.

Post Tensioning Institute (PTI) Parameters (Continued)

Building(s) PVR DesignOption

Edge Moisture VariationDistance, em 1, 2, 3

Differential Soil Movement,ym (Center Lift) 2, 3

Center Lift Edge Lift Center Lift Edge Lift

1, 2, 3, 4, 7, 8, 9,10, 11, 12, 13, 14

1-inch 8.0 feet 4.2 feet 1-inch 1-inch1½-inch 8.0 feet 4.1 feet 1.1 inches 1-inch

Building 5 & 19(Clubhouse)

1-inch 8.5 feet 4.3 feet 1.3 inches 1-inch1½-inch 8.3 feet 4.3 feet 1.6 inches 1.1 inches

2. Post-Tensioning Institute, “Addendum No. 1 to the 3rd Edition of the Design of Post-Tensioned Slabs-on-Ground”, Post-Tensioning Institute, Phoenix, AZ, May 2007.



Post Tensioning Institute (PTI) Parameters for Subgrade Prepared as in Section 4.3 1

Building 6 & 171-inch 8.0 feet 4.2 feet 1.1 inches 1 inch

1½-inch 7.8 feet 4.1 feet 1.3 inches 1-inch

Buildings 15, 16& 18

1-inch 7.8 feet 4.0 feet 1-inch 1-inch1½-inch 7.5 feet 3.9 feet 1.1 inches 1-inch

1. The maximum moisture variation distance is termed the edge moisture variation distance, em, and is animportant factor governing the design of post-tensioned floor slabs. The em is related to percent fine clayand climatic conditions as well as other parameters, such as soil fabric factor and unsaturated diffusioncoefficient.

2. The differential movements, ym, and edge moisture variation distances, em, were calculated by modelingsoil profiles using the commercial software program VOLFLO as recommended by the PTI manual.

3. For subgrade prepared as in Section 4.3.

When considering a grade-supported floor slab, the design of the floor slab involves theinteraction of the floor slab and the soil support system to resist moments and shears induced bythe applied structural loads. Floor slabs can be thickened, or stiffening beams can be added, toaid in resisting moments and shears. Expansive soils are the primary concern at this site.Recommendations to reduce the risk associated with these soils are presented in Section 4.3 –Floor Slab Subgrade Preparation. Joints should be constructed at regular intervals asrecommended by the American Concrete Institute (ACI) to help control the location of anycracking.

For a slab foundation system designed and constructed as recommended in this report, post-construction settlements should about 1-inch. Settlement response of a select fill supported slabis influenced more by the quality of construction than by soil-structure interaction. Therefore, it isessential that the recommendations for foundation construction be strictly followed during theconstruction phases of the building pad and foundation.

The use of a vapor retarder should be considered beneath concrete slabs-on-grade that will becovered with wood, tile, carpet or other moisture-sensitive or impervious coverings, or when theslabs will support equipment sensitive to moisture. When conditions warrant the use of a vaporretarder, the slab designer and slab contractor should refer to ACI 302 for procedures andcautions about the use and placement of a vapor retarder.

4.4.2 Foundation Construction ConsiderationsSlab-on-Grade

Grade beams and footings should be neat excavated if possible. If neat excavation is not possible,the foundation should be properly formed. If a toothed bucket is used, excavation with this bucketshould be stopped approximately 6 inches above final grade and the grade beam/footingexcavation completed with a smooth-mouthed bucket or by hand labor. Debris in the bottom ofthe excavation should be removed prior to steel placement. The foundation excavation should be



sloped sufficiently to create internal sumps for runoff collection and removal. If surface runoffwater or groundwater seepage in excess of one inch accumulates at the bottom of the foundationexcavation, it should be collected, removed, and not allowed to adversely affect the quality of thebearing surface.

If used, the post-tensioned slab-on-grade construction technique should be carefully monitoredby qualified personnel. The sophistication of this construction procedure requires careful attentionto details such as concrete integrity and anchorages, along with tendon spacing, support,covering, and stressing. Poor construction could result in a non-functional slab foundation system.

Foundation Construction MonitoringThe performance of the foundation system for the proposed structure will be highly dependentupon the quality of construction. Thus, we recommend that the foundation installation bemonitored by Terracon to identify the proper bearing strata and depths and to help evaluatefoundation construction. We would be pleased to develop a plan for foundation monitoring to beincorporated in the overall quality control program.

4.5 Seismic Design Information

Code Used Seismic DesignCategory Site Classification

2012 International Building Code (IBC) A1 D2

1. Per IBC 2012 Section 1613.3.1.2. Per IBC 2012 Table 1613.3.2. The 2012 IBC requires a site soil profile determination extending a

depth of 100 feet for seismic site classification. The current scope does not include the required 100-foot soil profile determination. Borings extended to a maximum depth of approximately 20 feet andthis seismic site class definition assumes that materials with similar characteristics are below themaximum depth of the subsurface exploration. Additional exploration to deeper depths would berequired to confirm the conditions below the current depth of exploration. Alternatively, a geophysicalexploration could be used in order to attempt to justify a higher seismic class. If you desireparameters for earlier versions of IBC, please contact us.

Ground Motion Parameter Value (g)1

Ss 0.064S1 0.034

SMS 0.103SM1 0.082SDS 0.068SD1 0.055

1. Site Latitude 30.38391°N and Longitude 97.64413°W.



4.6 Lateral Earth Pressures

Presented below are at-rest, active, and passive earth pressure coefficients for various backfilltypes adjacent to below-grade walls or site retaining walls. At-rest earth pressures arerecommended in cases where little wall yield is expected (such as structural below-grade walls).Active earth pressures may be used in cases where the walls can exhibit a certain degree ofhorizontal movement (such as cantilevered retaining walls). The recommendations in this sectionapply to those walls which are installed in open cut or embankment fill areas such that the backfillextends out from the base of the wall at an angle of at least 45 degrees from vertical for the entireheight and length of the wall.

Backfill TypeEstimatedTotal Unit

Weight (pcf)

Lateral Earth Pressure Coefficients1

At Rest (KO) Active (KA) Passive (KP)

Crushed Limestone 140 0.45 0.3 3.5Clean Sand 120 0.5 0.35 3.0Clean Gravel 120 0.45 0.3 3.51. Coefficients represent ultimate values. Appropriate safety factors should be applied.

The above values do not include a hydrostatic or ground-level surcharge component. To preventhydrostatic pressure build-up, retaining walls should incorporate functional drainage (via free-draining aggregate or manufactured drainage mats) within the backfill zone. The effect ofsurcharge loads, where applicable, should be incorporated into wall pressure diagrams by addinga uniform horizontal pressure component equal to the applicable lateral earth pressure coefficienttimes the surcharge load, applied to the full height of the wall.

The compactive effort should be controlled during backfill operations adjacent to walls.Overcompaction can produce lateral earth pressures in excess of at-rest magnitudes. Compactionlevels adjacent to walls should be maintained between 95 and 100 percent of Standard Proctor(ASTM D 698) maximum dry density.

For retaining walls bearing on on-site soils, we recommend a coefficient of sliding resistance of0.4 (maximum allowable sliding resistance of 500 psf) and a maximum footing bearing capacityof 2,500 psf. All retaining walls should be checked against failure due to overturning, sliding, andoverall slope stability. Such an analysis can only be performed once the dimensions of the walland cut/fill scenarios are known. Retaining walls placed to bear upon the highly expansive StratumI/II fat clays observed on this site will be subject to the potential movements described previously(up to about 6¾ inches).

We recommend that a buffer area of at least 5 feet for all pavement areas be placed betweenretaining walls (with a minimum height of 4 feet or more), and the adjacent construction. In buildingareas, this buffer zone from retaining walls should be increased to at least 10 feet. These



recommended buffer zones are to reduce the potential of distress from any long-term (“creep”)movements of the wall and backfill. Pedestrian sidewalks may be exempted from the abovecriteria; however, some distress could still be observed in the sidewalks due to movements of theretaining walls and backfill.

A wall drain (consisting of freely-draining aggregate or manufactured drainage mat, along withoutlet piping) is recommended for collection and removal of surface water percolation behind thewalls. Proper control of surface water percolation will help to prevent buildup of higher wallpressures. In unpaved areas, the final 12 inches of backfill should preferably consist of clayeysoils to help to reduce percolation of surface water into the backfill.

4.7 Pavements

Both flexible (asphaltic concrete) and rigid (reinforced Portland cement concrete) pavementsystems may be considered for site pavement applications. These two types of pavement are notconsidered equal. Over the life of the pavement, concrete pavements would be expected to exhibitbetter performance and require less maintenance.

Detailed traffic loads and frequencies were not available for the pavements. However, weanticipate that traffic will consist primarily of passenger vehicles in the parking areas (assumedas the light duty pavements) and passenger vehicles combined with occasional garbage anddelivery/moving trucks in driveways (assumed as light-medium duty pavements). If heavier trafficloading is expected or other traffic information is available, Terracon should be provided with theinformation and allowed to review the pavement sections provided herein. Tabulated below arethe assumed traffic frequencies and loads used to design pavement sections for this project.

Pavement Type Traffic Design Index Description

Parking Areas(Passenger VehiclesOnly):

DI-1

Light traffic – Few vehicles heavier thanpassenger cars, panel, and pick-up trucks; noregular use by heavily loaded two-axle trucks orlightly loaded larger vehicles. (EAL* < 5)

Driveways andDumpster Enclosures(Light-Medium Duty):

DI-2

Light to medium traffic – Similar to DI-1,including not over 50 heavily loaded two-axletrucks or lightly loaded larger vehicles per day.No regular use by heavily loaded trucks withthree or more axles. (EAL = 6 – 20)

* Equivalent daily 18-kip single axle load applications.

Lime treatment of fat clay subgrade soils, such as the on-site Stratum I/II soils, typically enhancesthe workability and support characteristics of the subgrade, as well as provides a barrier to reducemoisture infiltration into the underlying clay subgrade. Lime treatment also typically helps toreduce the shrink/swell potential of the lime-treated layer. However, excessive concentrations of



sulfates in the soils can result in poor performance of lime treated subgrade. Based on ourprevious experience, lime treatment is rarely considered in the Austin area for multi-familyapartment projects such as this, therefore we have not provided lime treated subgrade pavementsections in this report. If this is desired, please contact us. If lime treatment of the subgrade isplanned, we recommend that the subgrade soils be further investigated for the presence ofsulfates during construction.

Listed below are pavement component thicknesses which may be used as a guide for pavementsystems at the site assuming that the on-site soils will generally act as the pavement subgrade,and that the pavement subgrade is prepared as outlined in the “Moisture Conditioned Subgrade”portions of this section and in accordance with our general recommendations for site preparationin Section 4.2 – Earthwork. We should note that these systems were derived based on generalcharacterization of the subgrade. No specific testing (such as CBR, resilient modulus tests, etc.)was performed for this project to evaluate the support characteristics of the subgrade.

FLEXIBLE PAVEMENT SYSTEM

ComponentMaterial Thickness (Inches)DI-1 DI-2

Asphaltic Concrete (HMAC) 2.0 2.5

Crushed Limestone Base 9.0 10.0

Moisture Conditioned Subgrade 6.0 6.0

RIGID PAVEMENT SYSTEM

ComponentMaterial Thickness (Inches)DI-1 DI-2

Reinforced Concrete 5.0 6.0

Moisture Conditioned Subgrade 6.0 6.0 1

1. Dumpster pads should be constructed with 7 inches of concrete over moisture conditionedsubgrade.

Reinforcing Steel: #3 bars spaced at 18 inches on centers in both directions.

Control Joint Spacing: In accordance with ACI 330R-08, control joints should be spacedno greater than 12.5 feet for 5-inch thick concrete and no greaterthan 15 feet for 6-inch thick or greater concrete. If sawcut, controljoints should be cut within 6 to 12 hours of concrete placement.Sawcut joints should be at least ¼ of the slab thickness.

Expansion Joint Spacing: ACI 330R-08 indicates that regularly spaced expansion joints maybe deleted from concrete pavements. Therefore, the installation of



expansion joints is optional and should be evaluated by thedesign/construction team. Expansion joints, if not sealed andmaintained, can allow infiltration of surface water into thesubgrade.

Dowels at Expansion Joints: ¾-inch smooth bars, 18 inches in length, with one end treated toslip, spaced at 12 inches on centers at each joint.

Presented below are our recommended material requirements for the various pavement sections.

Hot Mix Asphaltic Concrete (HMAC) – The asphaltic concrete surface course should beplant mixed, hot laid Type D (Fine-Graded Surface Course) meeting the masterspecification requirements in TxDOT Item 340 or City of Austin (COA) Item 340. Foracceptance and payment evaluation purposes, we suggest considering the use of theprovisions in COA Item 340.

Reinforced Portland Cement Concrete (PCC) – Concrete should be designed to exhibit aflexural strength (third-point loading) of at least 500 psi at 28 days. As an option, a 28-daycompressive strength of 3,500 psi may be used.

Crushed Limestone Base – Base material should be composed of crushed limestonemeeting the requirements of TxDOT Item 247, Type A, Grade 1 or COA Item 210. Thebase should be compacted to a minimum of 95 percent of the maximum density asdetermined by the modified moisture/density relation (ASTM D 1557) at -3 to +3 percentof optimum moisture content. (As an option, compaction to at least 100 percent of theTEX-113-E maximum dry density may also be considered.) Each lift of base should bethoroughly proofrolled just prior to placement of subsequent lifts and/or asphalt. Particularattention should be paid to areas along curbs and adjacent to landscape islands and stormdrain inlets. Placement of the base material should extend at least 12 inches behind curbs.

Moisture Conditioned Subgrade – The soil subgrade should be scarified to a depth of 6inches, moisture conditioned, and recompacted to at least 95 percent of the maximum drydensity as determined by ASTM D 698. Select fill and on-site soils should be moistureconditioned and compacted as described in Section 4.2.1 – Compaction Requirements.Care should be taken such that the subgrade does not dry out or become saturated priorto pavement construction. The pavement subgrade should be thoroughly proofrolled witha rubber-tired vehicle (fully loaded water or dump truck) immediately prior placement ofbase material. Particular attention should be paid to areas along curbs and adjacent tolandscape islands and storm drain inlets. Placement of the moisture conditioned subgradeshould extend at least 18 inches behind curbs.



Pavement design methods are intended to provide structural sections with adequate thicknessover a particular subgrade such that wheel loads are reduced to a level the subgrade can support.The support characteristics of the subgrade for pavement design do not account for shrink/swellmovements of an expansive clayey subgrade. Thus, the pavement may be adequate from astructural standpoint, yet still experience cracking and deformation due to shrink/swell relatedmovement of the subgrade. It is, therefore, important to minimize moisture changes in thesubgrade to reduce shrink/swell movements. Proper perimeter drainage should be provided sothat infiltration of surface water from unpaved areas surrounding the pavement is minimized.

On most projects, rough site grading is accomplished relatively early in the construction phase.Fills are placed and compacted in a uniform manner. However, as construction proceeds,excavations are made into these areas; dry weather may desiccate some areas; rainfall andsurface water saturates some areas; heavy traffic from concrete and other delivery vehiclesdisturbs the subgrade; and many surface irregularities are filled in with loose soils to temporarilyimprove subgrade conditions. As a result, the pavement subgrade should be carefully evaluatedas the time for pavement construction approaches. This is particularly important in and aroundutility trench cuts. All pavement areas should be moisture conditioned and properly compacted tothe recommendations in this report immediately prior to paving. Thorough proofrolling ofpavement areas using a fully-loaded water truck or dump truck (rubber-wheeled vehicle that canimpart point wheel loads) should be performed no more than 36 hours prior to surface paving.Any problematic areas should be reworked and compacted at that time.

Openings in pavement, such as landscape islands, are sources for water infiltration intosurrounding pavements. Water collects in the islands and migrates into the surrounding basematerial and subgrade soils thereby degrading support of the pavement. The civil design for thepavements should include features to restrict or to collect and discharge excess water from theislands. Examples of features are self-contained planters, edge drains connected to the stormwater collection system or other suitable outlet, and impermeable barriers preventing lateralmigration of water such as a cutoff wall installed to a depth below the pavement structure.

Long-term pavement performance will be dependent upon several factors, including maintainingsubgrade moisture levels and providing for preventive maintenance. The followingrecommendations should be considered at a minimum:

■ Adjacent site grading at a minimum 2% grade away from the pavements;■ A minimum ¼ inch per foot slope on the pavement surface to promote proper surface

drainage;■ Install joint sealant and seal cracks immediately;■ Placing compacted, low permeability clay backfill against the exterior side of curb and

gutter; and,■ Placing curb and gutters through any base material and directly on subgrade soils.



Preventive maintenance should be planned and provided for through an on-going pavementmanagement program. These activities are intended to slow the rate of pavement deteriorationand to preserve the pavement investment. Preventive maintenance consists of both localizedmaintenance (e.g. crack and joint sealing and patching) and global maintenance. This is usuallythe first priority when implementing a planned pavement maintenance program and provides thehighest return on investment for pavements. Prior to implementing any maintenance, additionalengineering observation is recommended to determine the type and extent of preventivemaintenance.

5.0 GENERAL COMMENTS

Terracon should be retained to review the final design plans and specifications so comments canbe made regarding interpretation and implementation of our geotechnical recommendations inthe design and specifications. Terracon also should be retained to provide testing and observationduring excavation, grading, foundation installation, and other construction phases of the project.

The analysis and recommendations presented in this report are based upon the data obtainedfrom the borings performed at the indicated locations and from other information discussed in thisreport. This report does not reflect variations that may occur between borings, across the site, ordue to the modifying effects of weather. The nature and extent of such variations may not becomeevident until during or after construction. If variations appear, we should be immediately notifiedso that further evaluation and supplemental recommendations can be provided.

The scope of services for this project does not include, either specifically or by implication, anyenvironmental or biological (e.g., mold, fungi, bacteria) assessment of the site or identification orprevention of pollutants, hazardous materials, or conditions. If the owner is concerned about thepotential for such contamination or pollution, other studies should be undertaken.

For any excavation construction activities at this site, all Occupational Safety and HealthAdministration (OSHA) guidelines and directives should be followed by the Contractor duringconstruction to provide a safe working environment. In regards to worker safety, OSHA Safetyand Health Standards require the protection of workers from excavation instability in trenchsituations.

This report has been prepared for the exclusive use of our client for specific application to theproject discussed and has been prepared in accordance with generally accepted geotechnicalengineering practices. No warranties, either express or implied, are intended or made. Site safety,excavation support, and dewatering requirements are the responsibility of others. In the eventthat changes in the nature, design, or location of the project as outlined in this report are planned,the conclusions and recommendations contained in this report shall not be considered valid



unless Terracon reviews the changes and either verifies or modifies the conclusions of this reportin writing.

APPENDIX AFIELD EXPLORATION

SITE VICINITY PLAN

A-15307 Industrial Oaks Blvd, Suite 160 Austin, Texas 78735

PH. (512) 442-1122 FAX. (512) 442-1181

96145163

10/30/2014

ADK

ADK

ADK

ADK

N.T.S.

Project Manager:

Drawn by:

Checked by:

Approved by:

Project No.

Scale:

File Name:

Date:

Exhibit

96145163DIAGRAM IS FOR GENERAL LOCATIONONLY, AND IS NOT INTENDED FOR

CONSTRUCTION PURPOSES

SITE

CREEKSIDE ON PARMERE. PARMER LANE, HARRIS BRANCH TRACT E-33

AUSTIN, TEXAS

BORING LOCATION DIAGRAM


PH. (512) 442-1122 FAX. (512) 442-1181

96145163

10/30/2014

ADK

ADK

ADK

ADK

AS SHOWN

Project Manager:

Drawn by:

Checked by:

Approved by:

Project No.

Scale:

File Name:

Date:

Exhibit

96145163DIAGRAM IS FOR GENERAL LOCATION

ONLY, AND IS NOT INTENDED FORCONSTRUCTION PURPOSES. SCALE

SHOWN IS APPROXIMATE.


AUSTIN, TEXAS

B-18B-19

B-1 B-2

B-3

B-4B-5 B-6 B-8

B-9B-7

B-10B-11

B-12

B-13 B-14

B-15

B-16B-17

BORING LOCATION AERIAL


PH. (512) 442-1122 FAX. (512) 442-1181

96145163

10/30/2014

ADK

ADK

ADK

ADK

AS SHOWN

Project Manager:

Drawn by:

Checked by:

Approved by:

Project No.

Scale:

File Name:

Date:

Exhibit

96145163DIAGRAM IS FOR GENERAL LOCATION

ONLY, AND IS NOT INTENDED FORCONSTRUCTION PURPOSES. SCALE

SHOWN IS APPROXIMATE.

B-1


AUSTIN, TEXAS

B-2B-3

B-4

B-18B-19

B-5

B-6 B-8

B-9B-7

B-10B-11

B-12

B-14B-13

B-15

B-17B-16

Geotechnical Engineering ReportCreekside on Parmer ■ Austin, Texas ■ Terracon Project No. 96145163November 11, 2014 ■ Terracon Project No. 96145163

Exhibit A-4

Field Exploration Description

Subsurface conditions were evaluated by drilling seventeen (17) borings (B-1 through B-17) todepths of about 15 to 20 feet within the proposed building areas and two (2) borings (B-18 and B-19) to depths of about 5 feet within the proposed pavement areas. Prior to drilling, trees and brushwere cleared by others to provide pathways to the boring locations. The borings were drilled withtruck-mounted rotary drilling equipment at the approximate locations shown on Exhibits A-2 andA-3 of Appendix A. Boring depths were measured from the existing ground surface at the time ofour field activities. The boring coordinates were located in the field through the use of a Garminhandheld GPS unit. The coordinates are presented on the top of the boring logs. Elevations wereapproximated based on the site topography survey provided to us.

The boring logs, which include the subsurface descriptions, types of sampling used, andadditional field data for this study, are presented on the boring logs in Appendix A. Criteria definingterms, abbreviations and descriptions used on the boring logs are presented in Appendix C.

Soil samples were generally recovered using thin-walled, open-tube samplers (Shelby tubes). Apocket penetrometer test was performed on each sample of cohesive soil in the field to serve asa general measure of consistency.

Samples were removed from the samplers in the field, visually classified, and appropriately sealedin sample containers to preserve the in-situ moisture contents. Samples were then placed in coreboxes for transportation to our laboratory in Austin, Texas.

1.0

8.0

20.0

FAT CLAY (CH), dark brown, hard

LEAN CLAY WITH SAND (CL),calcareous nodules, light brown to tan toyellowish-brown, very stiff to hard

FAT CLAY (CH), yellowish-brown to tan,hard, blocky, marly

with gray seams below about 18 feet

Boring Terminated at 20 Feet

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

3.75 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5 tsf (HP)

UC 9.20 5.4

82

15

10

10

12

16

121

34-14-20

36-14-22

622.5+/-

615.5+/-

603.5+/-

Hammer Type: Rope and CatheadStratification lines are approximate. In-situ, the transition may be gradual.

LOCATION

DEPTH

GR

AP

HIC

LO

G Building 19/ClubhouseLatitude: 30.369332° Longitude: -97.620191°

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ

Parmer Lane, West of Cameron Road Austin, TexasSITE:

Page 1 of 1

Advancement Method:Dry Augered 0 to 20 feet

Abandonment Method:Backfilled with Auger Cuttings

5307 Industrial Oaks Blvd., Suite 160Austin, Texas

Notes:

Project No.: 96145163

Drill Rig: Mobile B-57

Boring Started: 10/7/2014

BORING LOG NO. B-1Austin HB Residential Properties, Ltd.CLIENT:Austin, Texas

Driller: Texas Geo Bore

Boring Completed: 10/7/2014

Exhibit:

Elevations approximated from the sitetopography plan provided to us.

A-5

See Appendix C for explanation of symbols andabbreviations.

See Appendix B for description of laboratoryprocedures and additional data (if any).

See Exhibit A-4 for description of fieldprocedures

PROJECT: Creekside on Parmer

FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)

Approximate Surface Elev: 623.5 (Ft.) +/- DE

PT

H (

Ft.)

5

10

15

20

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)

No free water observedWATER LEVEL OBSERVATIONS

4.0

15.0

FAT CLAY (CH), with scattered gravel,dark brown, hard

FAT CLAY (CH), with calcareousnodules, light brown to tan toyellowish-brown, hard, blocky, marly, withferrous staining


3.5 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 9.47 3.7

19

13

14

20

28

104 57-15-42

614.5+/-

603.5+/-


LOCATION

DEPTH

GR

AP

HIC

LO

G Building 1Latitude: 30.369313° Longitude: -97.619679°

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

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-33

BO

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G L

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S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-6





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


3.0

15.0


FAT CLAY (CH), light brown to tan toyellowish-brown, blocky, marly, withferrous staining



4.25 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 6.91 3

93

17

12

13

16

17

112

58-15-43

54-16-38

616+/-

604+/-

6.0


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-7





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)

Approximate Surface Elev: 619 (Ft.) +/- DE

PT

H (

Ft.)

5

10

15

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


4.0

12.0

15.0

LEAN CLAY (CL), with scattered gravel,dark brown to grayish-brown, hard

LEAN CLAY (CL), with calcareousnodules and scattered gravel and sandyseams, light brown to tan to grayish-tan,hard

FAT CLAY (CH), light brown to tan toyellowish-brown with gray seams, hard,marly, with ferrous staining


4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 11.43 4.2

60

16

9

6

5

9 122

41-25-16

35-16-19

39-15-24

616.5+/-

608.5+/-

605.5+/-


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-8





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


4.0

12.0

15.0

FAT CLAY (CH), dark brown to brown,hard, varies to lean clay (CL)

LEAN CLAY WITH SAND (CL), withcalcareous nodules, light brown to tan toyellowish-brown, hard, marly, with ferrousstaining

FAT CLAY (CH), tan to yellowish-brown,hard, blocky, marly, with ferrous staining


4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 15.14 5.9 71

15

11

9

9

9

122

47-16-31

42-15-27

615.5+/-

607.5+/-

604.5+/-


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-9





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


2.0

15.0

FAT CLAY (CH), dark brown to brown,very stiff to hard

FAT CLAY (CH), with calcareousnodules, light brown to tan toyellowish-brown, hard, marly, with ferrousstaining



3.5 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 12.27 6.3

22

13

18

20

16

116 63-16-47

75-22-53

611+/-

598+/-


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-10





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


3.0

15.0

FAT CLAY (CH), with scattered gravel,dark brown, very stiff to hard

FAT CLAY (CH), with calcareousnodules in the upper 10 feet, light brown tograyish-brown to tan, hard, blocky, marly,with ferrous staining



4.5 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 3.29 6.7 6214

15

15

21

21

111 61-18-43

79-22-57

609+/-

597+/-


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-11





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


2.0

20.0

FAT CLAY (CH), trace gravel, darkbrown, hard

FAT CLAY (CH), with calcareousnodules in the upper 6 feet, light brown tograyish-brown to tan to yellowish-brown,hard, blocky, marly, with ferrous staining


4.5 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 10.15 4

15

13

20

19

20

108

58-16-42

72-20-52

595.5+/-

577.5+/-

6.2


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-12





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

20

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


2.0

15.0

FAT CLAY (CH), trace gravel, darkbrown, hard

FAT CLAY (CH), with calcareousnodules in the upper 6 feet, light brown tograyish-brown to tan to yellowish-brown,hard, blocky, marly, with ferrous staining



4.25 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 10.30 3

18

13

12

22

21

103

67-15-52

78-22-56

588.5+/-

575.5+/-


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-13





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


2.0

20.0

FAT CLAY (CH), dark brown, stiff

FAT CLAY (CH), with calcareousnodules in the upper 4 feet, light brown tograyish-brown to tan, hard, blocky, marly,with ferrous staining



1.75 tsf (HP)

1.75 tsf (HP)

4.0 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 4.00 3.9

23

18

23

24

22

105 61-18-43

79-22-57

605+/-

587+/-

6.0


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-14





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

20

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


6.0

15.0

FAT CLAY (CH), with calcareousnodules in the lower 2 feet, dark brown,hard

FAT CLAY (CH), trace calcareousnodules, light brown to grayish-brown totan to yellowish-brown, hard, blocky,marly, with ferrous staining



4.5 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 12.05 3.7

99

24

24

15

17

19

112

70-18-52

69-19-50

583+/-

574+/-


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-15





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


3.0

15.0

FAT CLAY (CH), with calcareousnodules, dark brown, hard

FAT CLAY (CH), trace calcareousnodules, light brown to grayish-brown totan to yellowish-brown, hard, blocky,marly, with ferrous staining


4.25 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 3.34 7.3 22

23

25

25

22

104

85-23-62

73-23-50

589.5+/-

577.5+/-

5.9


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

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Page 1 of 1




Notes:







Exhibit:


A-16





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


5.0

15.0

FAT CLAY (CH), with calcareousnodules in the lower 2 feet, dark brown,hard

FAT CLAY (CH), with calcareousnodules in the upper 3 feet, light brown tograyish-brown to tan to yellowish-brownwith gray seams, hard, blocky, marly, withferrous staining


4.25 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 4.76 3 95

26

21

21

20

19

98 69-16-53

76-19-57

592+/-

582+/-


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-17





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


2.0

20.0

FAT CLAY (CH), dark brown tograyish-brown, hard

FAT CLAY (CH), trace calcareousnodules, light brown to grayish-brown totan to yellowish-brown, very stiff above 4feet, hard below about 4 feet, blocky,marly, with ferrous staining

with gypsum seams at about 18 feet


2.5 tsf (HP)

3.5 tsf (HP)

4.5 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 5.12 2.6

28

26

22

21

24

103

76-18-58

75-20-55

583+/-

565+/-

5.6


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-18





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

20

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


6.0

15.0

FAT CLAY (CH), dark brown tograyish-brown, stiff to hard



1.5 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 7.26 6.3

25

20

22

16

15

106 79-19-60

56-13-43

587+/-

578+/-


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

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S.G

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Page 1 of 1




Notes:







Exhibit:


A-19





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


4.0

15.0

FAT CLAY (CH), with calcareousnodules in the lower 2 feet, dark brown,stiff to hard

FAT CLAY (CH), trace calcareousnodules, light brown to grayish-brown totan to yellowish-brown with gray seams,hard, blocky, marly, with ferrous staining


2.25 tsf (HP)

4.25 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 8.04 6.6

98

29

22

18

23

22

111

79-18-61

84-21-63

582+/-

571+/-


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-20





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


2.0

20.0

FAT CLAY (CH), dark brown tograyish-brown, stiff to very stiff



2.0 tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 2.70 4.7 27

12

17

22

26

97

75-18-57

89-20-69

582+/-

564+/-

5.7


LOCATION

DEPTH

GR

AP

HIC

LO


TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-21





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

10

15

20

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


4.0

5.0


FAT CLAY (CH), trace calcareousnodules, light brown to grayish-brown totan to yellowish-brown with gray seams,hard, blocky, marlyBoring Terminated at 5 Feet

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 6.57 5.8 17

16

11

106

621.5+/-

620.5+/-


LOCATION

DEPTH

GR

AP

HIC

LO

G Entry Pavement AreaLatitude: 30.369787° Longitude: -97.620603°

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-22





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


4.0

5.0


FAT CLAY (CH), trace calcareousnodules, light brown to grayish-brown totan to yellowish-brown with gray seams,hard, blocky, marlyBoring Terminated at 5 Feet

4.5+ tsf (HP)

4.5+ tsf (HP)

4.5+ tsf (HP)

UC 6.23 2.6 26

14

13

90 66-16-50

619.5+/-

618.5+/-


LOCATION

DEPTH

GR

AP

HIC

LO

G Entry Pavement AreaLatitude: 30.369555° Longitude: -97.619913°

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

G

EO

SM

AR

T L

OG

-NO

WE

LL 9

614

516

3 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ


Page 1 of 1




Notes:







Exhibit:


A-23





FIE

LD T

ES

TR

ES

ULT

S

TE

ST

TY

PE

CO

MP

RE

SS

IVE

ST

RE

NG

TH

(tsf

)

ST

RA

IN (

%)

STRENGTH TEST

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

DR

Y U

NIT

WE

IGH

T (

pcf)

ATTERBERGLIMITS

LL-PL-PI

ELEVATION (Ft.)


PT

H (

Ft.)

5

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

SW

ELL

(%

)


APPENDIX BLABORATORY TESTING


Exhibit B-1

Laboratory Testing

Samples obtained during the field program were visually classified in the laboratory by ageotechnical engineer. A testing program was conducted on selected samples, as directed by thegeotechnical engineer, to aid in classification and evaluation of engineering properties requiredfor analyses.

Results of the laboratory tests are presented on the boring logs located in Appendix A and/or arediscussed in Section 3.0 – Subsurface Conditions of the report. Laboratory test results wereused to classify the soils encountered as generally outlined by the Unified Soil ClassificationSystem.

Samples not tested in the laboratory will be stored for a period of 30 days subsequent to submittalof this report and will be discarded after this period, unless we are notified otherwise.

0

5

10

15

20

25

30

35

40

45

50

55

60

65

70

75

80

85

90

95

100

0.0010.010.1110100

6 16 20 30 40 501.5 2006 810

81.8

92.9

59.7

70.9

62.4

0.0

0.8

12.1

3.1

22.0

14

LL PL PI

%Clay%Silt

41 3/4 1/2 60

fine

HYDROMETERU.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS

14

15

16

15

18

20

43

19

27

43

D100

Cc Cu

SILT OR CLAY

4

%Sand%GravelD30 D10

B-1

B-3

B-4

B-5

B-7

LEAN CLAY with SAND(CL)

FAT CLAY(CH)

SANDY LEAN CLAY(CL)

LEAN CLAY with SAND(CL)

GRAVELLY FAT CLAY with SAND(CH)

34

58

35

42

61

0.079

4.75

9.5

9.5

9.5

9.5

B-1

B-3

B-4

B-5

B-7

2.0

4.0

4.0

6.0

0.0

GRAIN SIZE IN MILLIMETERS

PE

RC

EN

T F

INE

R B

Y W

EIG

HT

coarse fine

3/8 3 100 1403 2

COBBLESGRAVEL SAND

USCS Classification

18.2

6.3

28.2

26.0

15.7

D60

coarse medium

2.0

4.0

4.0

6.0

0.0

Boring ID Depth

Boring ID Depth

GRAIN SIZE DISTRIBUTIONASTM D422


PROJECT NUMBER: 96145163PROJECT: Creekside on Parmer

SITE: Parmer Lane, West of Cameron Road Austin, Texas

CLIENT: Austin HB Residential Properties,Ltd. Austin, Texas

EXHIBIT: B-2

LAB

OR

AT

OR

Y T

ES

TS

AR

E N

OT

VA

LID

IF S

EP

AR

AT

ED

FR

OM

OR

IGIN

AL

RE

PO

RT

.

GR

AIN

SIZ

E: U

SC

S-2

961

451

63 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ

TE

RR

AC

ON

2012

.GD

T

11/1

1/14

0

5

10

15

20

25

30

35

40

45

50

55

60

65

70

75

80

85

90

95

100

0.0010.010.1110100

6 16 20 30 40 501.5 2006 810

98.8

95.4

98.1

0.0

0.0

0.0

14

LL PL PI

%Clay%Silt

41 3/4 1/2 60

fine

HYDROMETERU.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS

19

16

21

50

53

63

D100

Cc Cu

SILT OR CLAY

4

%Sand%GravelD30 D10

B-11

B-13

B-16

FAT CLAY(CH)

FAT CLAY(CH)

FAT CLAY(CH)

69

69

84

4.75

4.75

4.75

B-11

B-13

B-16

6.0

2.0

8.0

GRAIN SIZE IN MILLIMETERS

PE

RC

EN

T F

INE

R B

Y W

EIG

HT

coarse fine

3/8 3 100 1403 2

COBBLESGRAVEL SAND

USCS Classification

1.2

4.6

1.9

D60

coarse medium

6.0

2.0

8.0

Boring ID Depth

Boring ID Depth

GRAIN SIZE DISTRIBUTIONASTM D422


PROJECT NUMBER: 96145163PROJECT: Creekside on Parmer

SITE: Parmer Lane, West of Cameron Road Austin, Texas

CLIENT: Austin HB Residential Properties,Ltd. Austin, Texas

EXHIBIT: B-3

LAB

OR

AT

OR

Y T

ES

TS

AR

E N

OT

VA

LID

IF S

EP

AR

AT

ED

FR

OM

OR

IGIN

AL

RE

PO

RT

.

GR

AIN

SIZ

E: U

SC

S-2

961

451

63 H

AR

RIS

BR

AN

CH

TR

AC

T E

-33

BO

RIN

G L

OG

S.G

PJ

TE

RR

AC

ON

2012

.GD

T

11/1

1/14

APPENDIX CSUPPORTING DOCUMENTS

Exhibit: C-1

Unconfined Compressive StrengthQu, (tsf)

0.25 to 0.50

1.00 to 2.00

2.00 to 4.00

0.50 to 1.00

less than 0.25

> 4.00

Non-plasticLowMediumHigh

DESCRIPTION OF SYMBOLS AND ABBREVIATIONSS

AM

PL

ING

WA

TE

R L

EV

EL

FIE

LD

TE

ST

S

GENERAL NOTES

Over 12 in. (300 mm)12 in. to 3 in. (300mm to 75mm)3 in. to #4 sieve (75mm to 4.75 mm)#4 to #200 sieve (4.75mm to 0.075mmPassing #200 sieve (0.075mm)

Particle Size

< 55 - 12> 12

Percent ofDry Weight

Descriptive Term(s)of other constituents

RELATIVE PROPORTIONS OF FINES

01 - 1011 - 30

> 30

Plasticity Index

Soil classification is based on the Unified Soil Classification System. Coarse Grained Soils have more than 50% of their dryweight retained on a #200 sieve; their principal descriptors are: boulders, cobbles, gravel or sand. Fine Grained Soils haveless than 50% of their dry weight retained on a #200 sieve; they are principally described as clays if they are plastic, andsilts if they are slightly plastic or non-plastic. Major constituents may be added as modifiers and minor constituents may beadded according to the relative proportions based on grain size. In addition to gradation, coarse-grained soils are definedon the basis of their in-place relative density and fine-grained soils on the basis of their consistency.

LOCATION AND ELEVATION NOTES

Percent ofDry Weight

Major Componentof Sample

TraceWithModifier

RELATIVE PROPORTIONS OF SAND AND GRAVEL GRAIN SIZE TERMINOLOGY

TraceWithModifier

DESCRIPTIVE SOIL CLASSIFICATION

BouldersCobblesGravelSandSilt or Clay

Descriptive Term(s)of other constituents

N

(HP)

(T)

(DCP)

(PID)

(OVA)

< 1515 - 29> 30

Term

PLASTICITY DESCRIPTION

Water levels indicated on the soil boringlogs are the levels measured in theborehole at the times indicated.Groundwater level variations will occurover time. In low permeability soils,accurate determination of groundwaterlevels is not possible with short termwater level observations.

Water Level Aftera Specified Period of Time

Water Level After aSpecified Period of Time

Water InitiallyEncountered

ShelbyTube

Unless otherwise noted, Latitude and Longitude are approximately determined using a hand-held GPS device. The accuracyof such devices is variable. Surface elevation data annotated with +/- indicates that no actual topographical survey wasconducted to confirm the surface elevation. Instead, the surface elevation was approximately determined from topographicmaps of the area.

Standard Penetration TestResistance (Blows/Ft.)

Hand Penetrometer

Torvane

Dynamic Cone Penetrometer

Photo-Ionization Detector

Organic Vapor Analyzer

ST

RE

NG

TH

TE

RM

S Standard Penetration orN-Value

Blows/Ft.

Descriptive Term(Consistency)

Descriptive Term(Density)

CONSISTENCY OF FINE-GRAINED SOILS

(50% or more passing the No. 200 sieve.)Consistency determined by laboratory shear strength testing, field

visual-manual procedures or standard penetration resistance

Standard Penetration orN-Value

Blows/Ft.

(More than 50% retained on No. 200 sieve.)Density determined by Standard Penetration Resistance

RELATIVE DENSITY OF COARSE-GRAINED SOILS

Hard > 30

> 50 15 - 30Very Stiff

Stiff

Medium Stiff

Very Soft 0 - 1

Medium Dense

SoftLoose

Very Dense

8 - 1530 - 50Dense

4 - 810 - 29

2 - 44 - 9

Very Loose 0 - 3

Exhibit C-2

UNIFIED SOIL CLASSIFICATION SYSTEM

Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests A Soil Classification

Group Symbol Group Name B

Coarse Grained Soils: More than 50% retained on No. 200 sieve

Gravels: More than 50% of coarse fraction retained on No. 4 sieve

Clean Gravels: Less than 5% fines C

Cu 4 and 1 Cc 3 E GW Well-graded gravel F Cu 4 and/or 1 Cc 3 E GP Poorly graded gravel F

Gravels with Fines: More than 12% fines C

Fines classify as ML or MH GM Silty gravel F,G,H Fines classify as CL or CH GC Clayey gravel F,G,H

Sands: 50% or more of coarse fraction passes No. 4 sieve

Clean Sands: Less than 5% fines D

Cu 6 and 1 Cc 3 E SW Well-graded sand I Cu 6 and/or 1 Cc 3 E SP Poorly graded sand I

Sands with Fines: More than 12% fines D

Fines classify as ML or MH SM Silty sand G,H,I Fines classify as CL or CH SC Clayey sand G,H,I

Fine-Grained Soils: 50% or more passes the No. 200 sieve

Silts and Clays: Liquid limit less than 50

Inorganic: PI 7 and plots on or above “A” line J CL Lean clay K,L,M PI 4 or plots below “A” line J ML Silt K,L,M

Organic: Liquid limit - oven dried

0.75 OL Organic clay K,L,M,N

Liquid limit - not dried Organic silt K,L,M,O

Silts and Clays: Liquid limit 50 or more

Inorganic: PI plots on or above “A” line CH Fat clay K,L,M PI plots below “A” line MH Elastic Silt K,L,M

Organic: Liquid limit - oven dried

0.75 OH Organic clay K,L,M,P

Liquid limit - not dried Organic silt K,L,M,Q Highly organic soils: Primarily organic matter, dark in color, and organic odor PT Peat

A Based on the material passing the 3-inch (75-mm) sieve B If field sample contained cobbles or boulders, or both, add “with cobbles

and/or boulders” (or both) to group name. C Gravels with 5 to 12% fines require dual symbols: GW-GM well-graded

gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorly graded gravel with silt, GP-GC poorly graded gravel with clay.

D Sands with 5 to 12% fines require dual symbols: SW-SM well-graded sand with silt, SW-SC well-graded sand with clay, SP-SM poorly graded sand with silt, SP-SC poorly graded sand with clay

E Cu = D60/D10 Cc = 6010

2

30

DxD

)(D

F If soil contains 15% sand, add “with sand” to group name. G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM.

H If fines are organic, add “with organic fines” to group name. I If soil contains 15% gravel, add “with gravel” to group name. J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay. K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel,”

whichever is predominant. L If soil contains 30% plus No. 200 predominantly sand, add “sandy” to

group name. M If soil contains 30% plus No. 200, predominantly gravel, add

“gravelly” to group name. N PI 4 and plots on or above “A” line. O PI 4 or plots below “A” line. P PI plots on or above “A” line. Q PI plots below “A” line.

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