preliminary geotechnical engineering report · 2019-01-29 · preliminary geotechnical engineering...

REPORT COVER PAGE

Preliminary Geotechnical Engineering Report1800 Walnut

Kansas City, MissouriJanuary 29, 2018

Terracon Project No. 02185012.001

Prepared for:Copaken Brooks

Kansas City, Missouri

Prepared by:Terracon Consultants, Inc.

Lenexa, Kansas

Terracon Consul tants, Inc. 13910 W. 96 t h Terrace Lenexa, Kansas 66215P (913) 492 7777 F (913) 492 7443 terracon.com

REPORT COVER LET TER T O SIGN

January 29, 2018

Copaken Brooks1100 Walnut, Suite 2000Kansas City, Missouri 64106

Attn: Mr. Eric WyanckoP: (816) 701 5000E: [email protected]

Re: Preliminary Geotechnical Engineering Report1800 WalnutKansas City, MissouriTerracon Project No. 02185012.001

Dear Mr. Wyancko:

We have completed a limited geotechnical exploration for the above referenced project. Thisstudy was performed in general accordance with Terracon Proposal No. P02185012 datedJanuary 6, 2017. This preliminary report presents the findings of the subsurface exploration andprovides preliminary geotechnical recommendations concerning the design and construction offoundations for the proposed project.

We appreciate the opportunity to be of service to you on this project. If you have any questionsconcerning this report, or if we may be of further service, please contact us.

Sincerely,Terracon Consultants, Inc.

Daniel A. Barnett, P.G. Michael W. Laney, P.E.Project Geologist Senior AssociateMissouri: 2007035892 Missouri: PE-2014011241

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REPORT TOPICSREPORT TOPICS

INTRODUCTION ............................................................................................................. 1SITE CONDITIONS ......................................................................................................... 1GEOTECHNICAL CHARACTERIZATION ...................................................................... 1PROJECT DESCRIPTION .............................................................................................. 3GEOTECHNICAL OVERVIEW ....................................................................................... 4DEEP FOUNDATIONS ................................................................................................... 5GENERAL COMMENTS ................................................................................................. 5

Note: This report was originally delivered in a web-based format. Orange Bold text in the report indicates a referencedsection heading. The PDF version also includes hyperlinks which direct the reader to that section and clicking on the

logo will bring you back to this page. For more interactive features, please view your project online atclient.terracon.com.

ATTACHMENTS

EXPLORATION AND TESTING PROCEDURESSITE LOCATION AND EXPLORATION PLANSEXPLORATION RESULTS (Boring Log)SUPPORTING INFORMATION (General Notes and Unified Soil Classification System)

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INTRODUCTION

Preliminary Geotechnical Engineering Report1800 Walnut

Kansas City, MissouriTerracon Project No. 02185012.001

January 29, 2018

INTRODUCTION

This report presents the results of our subsurface exploration and geotechnical engineeringevaluation performed for the proposed apartment building to be located at 1800 Walnut in KansasCity, Missouri. One exploratory boring was performed at the site. This report describes thesubsurface conditions encountered at the site, presents the test data, and provides preliminarygeotechnical recommendations regarding excavation and foundations. Maps showing the siteand boring location are shown in the Site Location and Exploration Plan sections, respectively.

SITE CONDITIONS

The following description of site conditions is derived from our site visit in association with thefield exploration and our review of publicly available geologic and topographic maps.

Item Description

Project LocationThe project is located at 1800 Walnut Street in Kansas City, Missouri.39.091436° N, 94.582829° W (See Exhibit D)

ExistingImprovements The project site is an asphalt-surfaced parking lot.

Current Ground Cover Asphalt

Existing TopographyA topographic site plan was not provided. Based on topography obtainedfrom the Kansas City Missouri Geographic Information System (KCMO GIS),site grades slope down to the southwest.

GEOTECHNICAL CHARACTERIZATION

Site Geology

Based on our review of a Missouri Department of Natural Resources geologic publication, theproject site is located on the edge of the Abandoned Lower Turkey Creek Valley (ALTCV). TheALTCV is an ice-margin diversion channel with a length of approximately 6½ miles and a width ofapproximately ½ mile. A glacial ice lobe of pre-Illinoian age (0.5 to 2.5 million years before present)

Preliminary Geotechnical Engineering Report1800 Walnut ■ Kansas City, MissouriJanuary 29, 2018 ■ Terracon Project No. 02185012.001


dammed the Kansas River, which formed a large ice-margin lake to the west of present-day KansasCity. When the ice lobe dam melted, the water from the large ice-margin lake drained rapidly to theeast, carving the Pennsylvanian-age bedrock into a valley with a depth of over 240 feet. This deeplycarved valley was subsequently filled with alluvial soils. Alluvial clay soils were encountered at theboring locations to depths ranging from approximately 44½ to 52 feet bgs.

The alluvial clay soils were underlain by bedrock units of the Kansas City Group in the TimeStratigraphic Unit age classification. The specific bedrock members encountered were theWinterset Limestone Member and Stark Shale Member. These sedimentary strata were depositedprimarily in wide spread marine environments which covered much of the northwest Missouri andeastern Kansas and is known as the Forrest City Basin. Bedrock units comprise the valley wall ofthe ALTCV. Based on our knowledge of subsurface conditions in the vicinity of the site, the valleywall slopes down to the southeast at an apparent inclination of approximately 8(H):1(V).

Subsurface Profile

We have developed a general characterization of the subsurface soil and groundwater conditionsbased upon our review of the data and our understanding of the geologic setting and plannedconstruction. The following table provides our geotechnical characterization.

The geotechnical characterization forms the basis of our geotechnical calculations and evaluationof site preparation, foundation options and pavement options. As noted in General Comments,the characterization is based upon widely spaced exploration points across the site, and variationsare likely.

Stratum Approximate Depth toBottom of Stratum (bgs) Material Description Comments

1 8 inches Asphaltic concrete --

2 7½ feet Existing fillComposed of lean clay

soils with variableamounts of gravel

3 44½ feet Native lean clay

Contained sand andfine gravel below 33 ½

feet, very soft tomedium stiff

4 57 feet Winterset Limestone Member Slightly weathered

5

Undetermined: The boringterminated within thisstratum at a depth of

approximately 58¾ feet

Stark Shale Member Slightly weathered



Conditions encountered at the boring location are indicated on the boring log shown in theExploration Results section and are attached to this report. Stratification boundaries on theboring log represent the approximate location of changes in soil and rock types; in situ, thetransition between materials may be gradual.

Groundwater Conditions

The boring was advanced using mud rotary techniques wherein drilling fluid is pumped into theboring to flush cuttings and cool the drill bit. Introduction of drilling fluids into the boring masksindications of naturally occurring groundwater. Based on the historical borings, groundwater wasencountered at the site at depths ranging from approximately 17½ to 25 feet bgs. Long-termobservations in piezometers or observation wells, sealed from the influence of surface water,would be needed to develop more detailed groundwater information. Groundwater levelfluctuations occur due to variations in rainfall, runoff, and other factors not evident at the time theborings were drilled. The potential for groundwater level fluctuations should be considered whendeveloping the design and construction plans for the project.

PROJECT DESCRIPTION

Item Description

Proposed Structure

We understand the project includes construction of a 15-story apartmentbuilding and two-level parking garage. We understand the building andparking garage will be concrete-framed structures. The floor slab of theapartment building will be grade-supported.

Finished FloorElevation (FFE)

The FFE of the structure had not been determined at the time this report wasprepared. We considered the lowest level of the building and parkinggarage will be located within 2 feet of existing grades.

Maximum Loads

Anticipated structural loads for the structures were not provided. Weconsidered the following maximum loads:

■ Columns: 2,000 kips■ Walls: 5 kips per linear foot■ Slabs: 150 pounds per square foot

Grading/SlopesA site grading plan was not provided at the time this report was prepared. Inpreparing this report, we considered up to 2 feet of cut and fill will be requiredto develop final grades.

Below GradeStructures

We have not been informed of any planned below-grade structures. Weconsidered the structures will have below-grade elevator pits.

Free-StandingRetaining Walls None planned



GEOTECHNICAL OVERVIEW

Based on the subsurface conditions encountered at the boring locations and the estimated structuralloads of the building, we recommend the building be supported by drilled shaft foundations bearingin bedrock strata. The bedrock surface below the site has been eroded as described in Site Geologyand slopes down the southeast. As such, the bearing elevations of drilled shafts will be variable (i.e.drilled shafts constructed at the south end of the site will be longer that drilled shafts constructed atthe north end of the site). These conditions should be considered when estimating construction costsfor drilled shaft foundations. Drilled shaft design recommendations are provided in the followingsection of this report.

Terracon performed a ground penetrating radar (GPR) survey at the project site to search for thepresence of debris that could impact construction. The results of the GPR survey were providedunder separate cover (Terracon Report No. 02185012, dated January 24, 2018). Figure 1 belowwas contained in the referenced GPR report. Anomalies consistent with buried debris/foundationsand underground storage tanks (USTs) were identified with GPR. Construction of drilled shaftsthrough the buried debris could be difficult and require special procedures by the drilled shaftcontractor. These conditions should be considered when estimating construction costs for theproject.

Figure 1. GPR anomalies



DEEP FOUNDATIONS

Drilled Shaft Design Parameters

Depth(feet bgs)

Net Allowable EndBearing Pressure,

Q (psf) 2

Allowable Unit Skin Friction 3

Compressionsd (psf)

Upliftsu (psf)

0 to 3 1 Neglect Neglect Neglect

3 to 44½ Neglect Neglect 200

Below 44½ 60,000 2,000 1,500

1. Neglect soil resistance in upper 3 feet bgs to frost action and other disturbance.2. Considers a factor of safety of 2. The base of the drilled shafts must extend a minimum of 2 shaft diameters into

bedrock strata to achieve the recommended bearing capacities.3. Straight-sided drilled shafts cast in direct contact with adjacent clay soils and bedrock (uncased). Considers a

factor of safety of 2.

Allowable compressive capacity may be computed by multiplying the end area of the shaft timesthe end bearing value plus the area of the shaft sides within the rock socket times the allowableskin friction. Allowable tensile capacity may be calculated using the allowable unit skin friction inuplift for the various layers along the shaft, neglecting end bearing, and adding the weight of theshaft; only the portion of the shaft which is reinforced should be considered available to resistuplift forces.

Tensile reinforcement should extend to the bottom of shafts subjected to uplift loading. Buoyantunit weights of the soil and concrete should be used in the calculations below the highestanticipated groundwater elevation.

GENERAL COMMENTS

The general geotechnical considerations contained in this report are provided for preliminaryplanning purposes only. Terracon should be retained to review specific design development plansand to prepare design level geotechnical reports for specific structures. Terracon also should beretained to provide observation and testing services during grading, excavation, foundationconstruction and other earth-related construction phases of the project.

Our analysis and opinions are based upon our understanding of the project, the geotechnicalconditions in the area, and the data obtained from our site exploration. Natural variations will occurbetween exploration point locations or due to the modifying effects of construction or weather.The nature and extent of such variations may not become evident until during or after construction.Terracon should be retained to provide observation and testing services during pertinentconstruction phases. If variations appear, we can provide further evaluation and supplemental



recommendations. If variations are noted in the absence of our observation and testing serviceson-site, we should be immediately notified so that we can provide evaluation and supplementalrecommendations.

Our scope of services does not include either specifically or by implication any environmental orbiological (e.g., mold, fungi, bacteria) assessment of the site or identification or prevention ofpollutants, hazardous materials or conditions. If the owner is concerned about the potential forsuch contamination or pollution, other studies should be undertaken.

Our services and any correspondence or collaboration through this system are intended for thesole benefit and exclusive use of our client for specific application to the project discussed andare accomplished in accordance with generally accepted geotechnical engineering practices withno third party beneficiaries intended. Any third party access to services or correspondence issolely for information purposes to support the services provided by Terracon to our client. Relianceupon the services and any work product is limited to our client, and is not intended for third parties.Any use or reliance of the provided information by third parties is done solely at their own risk. Nowarranties, either express or implied, are intended or made.

Site characteristics as provided are for design purposes and not to estimate excavation cost. Anyuse of our report in that regard is done at the sole risk of the excavating cost estimator as theremay be variations on the site that are not apparent in the data that could significantly impactexcavation cost. Any parties charged with estimating excavation costs should seek their own sitecharacterization for specific purposes to obtain the specific level of detail necessary for costing.Site safety, and cost estimating including, excavation support, and dewateringrequirements/design are the responsibility of others. If changes in the nature, design, or locationof the project are planned, our conclusions and recommendations shall not be considered validunless we review the changes and either verify or modify our conclusions in writing.


ATTACH MENTS

ATTACHMENTS


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EXPLORATION PROCEDURES

Field Exploration

The boring was drilled with a track-mounted, rotary drill rig using continuous flight hollow-stemaugers and mud rotary technique to advance the borehole. A field log of the boring was preparedby a professional geologist during drilling operations. Samples of the soil encountered in the boringwas obtained using split-barrel sampling procedures. In the split-barrel sampling procedure, astandard 2-inch outside diameter split-barrel sampling spoon is driven into the ground by a140-pound automatic hammer falling a distance of 30 inches. The number of blows required toadvance the sampling spoon the last 12 inches of a normal 18-inch penetration is recorded as theStandard Penetration Test (SPT) resistance value. The SPT resistance values, also referred to asN-values, are indicated on the boring logs at the test depths.

The samples were tagged for identification, sealed to reduce moisture loss, and taken to ourlaboratory for further examination. The drill crew backfilled the boring with auger cuttings aftercompletion of drilling/sampling and prior to leaving the site. The existing pavement was patchedwith cold-asphalt patch product.

SITE LOCA TION AND EXPLORATI ON PLANS

SITE LOCATION AND EXPLORATION PLANS

SITE LOCATION1800 Walnut ■ Kansas City, MOJanuary 29, 2018 ■ Terracon Project No. 02185012

TOPOGRAPHIC MAP IMAGE COURTESY OF THE U.S. GEOLOGICAL SURVEYQUADRANGLES INCLUDE: KANSAS CITY, MO (1/1/1996).

DIAGRAM IS FOR GENERAL LOCATION ONLY, AND ISNOT INTENDED FOR CONSTRUCTION PURPOSES

SITE

EXPLORATION PLAN1800 Walnut ■ Kansas City, MOJanuary 29, 2018 ■ Terracon Project No. 02185012

DIAGRAM IS FOR GENERAL LOCATION ONLY, AND ISNOT INTENDED FOR CONSTRUCTION PURPOSES

AERIAL PHOTOGRAPHY PROVIDEDBY MICROSOFT BING MAPS

EXPLORATION RESULTS

EXPLORATION RESULTS

806.5+/-

799.5+/-

762.5+/-

750+/-

748.5+/-

1-1-1N=2

1-2-3N=5

WOH

3-4-6N=10

1-2-3N=5

2-2-3N=5

2-2-3N=5

4-2-2N=4

5-50/5"

50/2"

2

5

18

18

18

18

18

12

4

2

0.7

7.5

44.5

57.0

58.7

8" ASPHALTIC CONCRETEFILL - LEAN CLAY , trace gravel, brown and dark brown

LEAN CLAY (CL), gray brown and light brown, very soft to medium stiff

trace sand and fine gravel below 33.5 feet

LIMESTONE, gray, moderately to slightly weathered

SHALE, very dark gray and black, slightly weathered

Boring Terminated at 58.7 Feet

WOH: Weight of Hammer

GR

AP

HIC

LO

G

Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.Classification of rock materials has been estimated by the drill crew based on disturbed samples.Core samples and/or petrographic analysis may reveal other rock types.

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 0

2185

012

18

00 W

ALN

UT

.GP

J T

ER

RA

CO

N_D

AT

AT

EM

PLA

TE

.GD

T 1

/26

/18

ELEVATION (Ft.)

Approximate Surface Elev: 807 (Ft.) +/-

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

25

30

35

40

45

50

55

SA

MP

LE T

YP

E

FIE

LD T

ES

TR

ES

ULT

S

RE

CO

VE

RY

(In

.)

DEPTH

LOCATION See Exploration Plan

Latitude: 39.0915° Longitude: -94.5828°

Page 1 of 1

Advancement Method:Continuous flight hollow-stem auger: 0-10 feetMud rotary: below 10 feet

Abandonment Method:Boring backfilled with Auger Cuttings and/or Bentonite

13910 W 96th TerLenexa, KS

Notes:

Project No.: 02185012

Drill Rig: 988

Boring Started: 01-19-2018

BORING LOG NO. B-1Copaken BrooksCLIENT:Kansas City, Missouri

Driller: SF

Boring Completed: 01-19-2018

PROJECT: 1800 Walnut

Elevation obtained from mapping software

See Exploration and Testing Procedures for adescription of field and laboratory procedures usedand additional data (If any).

See Supporting Information for explanation ofsymbols and abbreviations.

1800 Walnut Street Kansas City, MissouriSITE:

WATER LEVEL OBSERVATIONSWater level not determined

SUPPORTING INFORMA TION

SUPPORTING INFORMATION

UNIFIED SOIL CLASSIFICATION SYSTEM1800 Walnut ■ Kansas City, MissouriJanuary 29, 2018 ■ Terracon Project No. 02185012.001UNIFIED SOI L CLASSI FICATI ON SYSTEM

Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests ASoil Classification

GroupSymbol Group Name B

Coarse-Grained Soils:More than 50% retainedon No. 200 sieve

Gravels:More than 50% ofcoarse fractionretained on No. 4 sieve

Clean Gravels:Less than 5% fines C

Cu ³ 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 coarsefraction passes No. 4sieve

Clean Sands:Less than 5% fines D

Cu ³ 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 theNo. 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 PeatA Based on the material passing the 3-inch (75-mm) sieveB If field sample contained cobbles or boulders, or both, add “with cobbles

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 poorlygraded gravel with silt, GP-GC poorly graded gravel with clay.

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

E Cu = D60/D10 Cc =6010

230

DxD

)(D

F If soil contains ³ 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 ³ 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 ³ 30% plus No. 200 predominantly sand, add

“sandy” to group name.MIf soil contains ³ 30% plus No. 200, predominantly gravel, add

“gravelly” to group name.NPI ³ 4 and plots on or above “A” line.OPI < 4 or plots below “A” line.P PI plots on or above “A” line.QPI plots below “A” line.

DESCRIPTION OF ROCK PROPERTIES1800 Walnut ■ Kansas City, MissouriJanuary 29, 2018 ■ Terracon Project No. 02185012.001ROCK VERSION 1

WEATHERINGTerm DescriptionUnweathered No visible sign of rock material weathering, perhaps slight discoloration on major discontinuity surfaces.Slightlyweathered

Discoloration indicates weathering of rock material and discontinuity surfaces. All the rock material may bediscolored by weathering and may be somewhat weaker externally than in its fresh condition.

Moderatelyweathered

Less than half of the rock material is decomposed and/or disintegrated to a soil. Fresh or discolored rock ispresent either as a continuous framework or as corestones.

Highlyweathered

More than half of the rock material is decomposed and/or disintegrated to a soil. Fresh or discolored rock ispresent either as a discontinuous framework or as corestones.

Completelyweathered All rock material is decomposed and/or disintegrated to soil. The original mass structure is still largely intact.

Residual soil All rock material is converted to soil. The mass structure and material fabric are destroyed. There is a largechange in volume, but the soil has not been significantly transported.

STRENGTH OR HARDNESS

Description Field Identification Uniaxial CompressiveStrength, psi (MPa)

Extremely weak Indented by thumbnail 40-150 (0.3-1)

Very weak Crumbles under firm blows with point of geological hammer, can bepeeled by a pocket knife 150-700 (1-5)

Weak rock Can be peeled by a pocket knife with difficulty, shallow indentationsmade by firm blow with point of geological hammer 700-4,000 (5-30)

Medium strong Cannot be scraped or peeled with a pocket knife, specimen can befractured with single firm blow of geological hammer 4,000-7,000 (30-50)

Strong rock Specimen requires more than one blow of geological hammer tofracture it 7,000-15,000 (50-100)

Very strong Specimen requires many blows of geological hammer to fracture it 15,000-36,000 (100-250)Extremely strong Specimen can only be chipped with geological hammer >36,000 (>250)

DISCONTINUITY DESCRIPTIONFracture Spacing (Joints, Faults, Other Fractures) Bedding Spacing (May Include Foliation or Banding)

Description Spacing Description SpacingExtremely close < ¾ in (<19 mm) Laminated < ½ in (<12 mm)

Very close ¾ in – 2-1/2 in (19 - 60 mm) Very thin ½ in – 2 in (12 – 50 mm)Close 2-1/2 in – 8 in (60 – 200 mm) Thin 2 in – 1 ft. (50 – 300 mm)

Moderate 8 in – 2 ft. (200 – 600 mm) Medium 1 ft. – 3 ft. (300 – 900 mm)Wide 2 ft. – 6 ft. (600 mm – 2.0 m) Thick 3 ft. – 10 ft. (900 mm – 3 m)

Very Wide 6 ft. – 20 ft. (2.0 – 6 m) Massive > 10 ft. (3 m)Discontinuity Orientation (Angle): Measure the angle of discontinuity relative to a plane perpendicular to the longitudinal axis of thecore. (For most cases, the core axis is vertical; therefore, the plane perpendicular to the core axis is horizontal.) For example, ahorizontal bedding plane would have a 0-degree angle.

ROCK QUALITY DESIGNATION (RQD) 1

Description RQD Value (%)Very Poor 0 - 25

Poor 25 – 50Fair 50 – 75

Good 75 – 90Excellent 90 - 100

1. The combined length of all sound and intact core segments equal to or greater than 4 inches in length, expressed as apercentage of the total core run length.

Reference: U.S. Department of Transportation, Federal Highway Administration, Publication No FHWA-NHI-10-034, December 2009Technical Manual for Design and Construction of Road Tunnels – Civil Elements

preliminary geotechnical engineering report · 2019-01-29 · preliminary geotechnical engineering...

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