GENERAL OVGENERAL OVGEOTECHNICGEOTECHNIC

HIGHWAY PHIGHWAY PHIGHWAY PHIGHWAY P

Lesson 1 Lesson 1

VERVIEW OF VERVIEW OF CAL INPUT TO CAL INPUT TO PROJECTSPROJECTSPROJECTSPROJECTS

-- Topic 2Topic 2

GENERAL OVERVGENERAL OVERVGEOTECHNICAL GEOTECHNICAL 1 Recognize the Import1 Recognize the Import1. Recognize the Import1. Recognize the Import

Theory, and ExperiencTheory, and Experienc2 Recall Basic Geotech2 Recall Basic Geotech2. Recall Basic Geotech2. Recall Basic Geotech

ACTIVITY:ACTIVITY: QuestionQuestion--

VIEW OF VIEW OF INPUTINPUT

tance of Testingtance of Testingtance of Testing, tance of Testing, cece

hnical Phaseshnical Phaseshnical Phaseshnical Phases

--AnswerAnswer

Geotechnical ParGeotechnical ParProject PhasesProject PhasesggPlanningPlanningggPlanningPlanning

-- Prepare Terrain ReconPrepare Terrain Recon-- Perform Site InspectionPerform Site InspectionPerform Site InspectionPerform Site Inspection

ggAlternate DesignAlternate Design-- Assess Major Soil ProbAssess Major Soil ProbAssess Major Soil ProbAssess Major Soil Prob-- Implement SubsurfaceImplement Subsurface

rticipation in rticipation in

nnaissance Reportnnaissance Reportnnnn

blemsblemsblemsblemse Programe Program

Geotechnical ParGeotechnical ParProject Phases (CProject Phases (CggAdvance Detailed PlanAdvance Detailed PlanggAdvance Detailed PlanAdvance Detailed Plan

-- Complete Testing and Complete Testing and -- Submit Foundation InvSubmit Foundation InvSubmit Foundation InvSubmit Foundation Inv

ggFinal DesignFinal Design-- Review Final PlansReview Final PlansReview Final PlansReview Final Plans-- Prepare PrePrepare Pre--bid Geotecbid Geotec

rticipation in rticipation in Cont’d)Cont’d)nsnsnsnsAnalysisAnalysis

vestigation Reportvestigation Reportvestigation Reportvestigation Report

chnical Packagechnical Package

Geotechnical ParGeotechnical ParProject Phases (CProject Phases (CggConstructionConstructionggConstructionConstruction

-- Brief Project StaffBrief Project Staff-- Trouble Shoot GeotechTrouble Shoot GeotechTrouble Shoot GeotechTrouble Shoot Geotech

ggPost ConstructionPost Construction-- Monitor ResultsMonitor ResultsMonitor ResultsMonitor Results-- Participate in Court of Participate in Court of

rticipation in rticipation in Cont’d)Cont’d)

hnical Problemshnical Problemshnical Problemshnical Problems

Claims ActionsClaims Actions

TestingTestinggg

ExperExperExperExper

TheoryTheoryTheoryTheory

riencerienceriencerience

Terrain ReconnaiTerrain Reconnaiissanceissance

Site InspectionSite Inspection

Subsurface BorinSubsurface Borinngsngs

Soil ProfileSoil Profile

Pipe Organ LandsPipe Organ LandsPreliminary Soil ProfilePreliminary Soil Profile

6000

5900

5800

57005700

5600

5500

5400Original GRND Line Test

Hole “B”

Test Hole “D”

5300

5200

5100

5000Test Hole5000

4900

0+00 5+00 10+00

Fault

Hole “C”

0+00 5+00 10+00

slideslide

6000

5900

5800

5700Test Hole Test 5700

5600

5500

5400

Test Hole “I”

Test Hole “E”

Hole “G” Hole

“F”Silt

Clayey Deposit

5300

5200

5100

5000

Water Table

Green Clay

5000

4900

15+00 20+00 26+0015+00 20+00 26+00

Typical Final SoilTypical Final Soil

Elevation (Ft.)Elevation (Ft.)560560

540540 Sand & Gravel (Fill)Sand & Gravel (Fill)33

520520

500500

Sand & Gravel (Fill)Sand & Gravel (Fill)

Medium DenMedium DenU-1U-1

500500

480480

Medium VMedium VU-2U-2

U-3U-3

44’

460460

440440

Very DSand &

Very DSand &

440440

l Profilel Profile

30’30’

nse Silty Sandnse Silty Sand N ≈ 17 (7 to 30) Blows/Ft.N ≈ 17 (7 to 30) Blows/Ft.

Varved ClayVarved ClayC = 900 PSFC = 900 PSFN ≈ 8 (6 to 12) Blows/Ft.N ≈ 8 (6 to 12) Blows/Ft.

Dense & GravelDense

& Gravel N ≈ 54 (28 to 96) Blows/Ft.N ≈ 54 (28 to 96) Blows/Ft.

Soil TestingSoil Testing

Coulomb’s EquatCoulomb’s EquatS= C + (Norma

S

CN

S

Φ

N

Φ

tiontional Force) Tan Φ

Φ

S

C

S = C

N

C

Geotechnical AnaGeotechnical Anaalysis alysis

Embankments Embankments Major Design ConMajor Design ConggStabilityStabilityggStabilityStabilityggSettlementSettlementggEff t St tEff t St tggEffects on Structure Effects on Structure

nsiderationsnsiderations

Design SolutionsDesign SolutionsEmbankment ProEmbankment ProggChange AlignmentChange AlignmentggChange AlignmentChange AlignmentggLower GradeLower GradeggC t bC t bggCounterbermCounterbermggExcavate and ReplaceExcavate and Replace

s to s to oblemsoblems

e Weak soilse Weak soils

Structural FoundaStructural Founda

ggShallow FoundationsShallow FoundationsggShallow Foundations Shallow Foundations -- Bearing CapacityBearing Capacity-- SettlementSettlement

ggDeep FoundationsDeep Foundations-- Load CapacityLoad Capacityp yp y-- SettlementSettlement-- Negative Skin FrictionNegative Skin Friction

ation Topicsation Topics

(Spread Footings)(Spread Footings)(Spread Footings)(Spread Footings)

nn

Shallow FoundatiShallow Foundati

Load, VLoad, VLoad, VLoad, V

nt, S

nt, S

nt, S

nt, S GeneralGeneralGeneralGeneral

Settl

eme

Settl

eme

Settl

eme

Settl

eme

LocalLocalLocalLocal

ion Failure Modeion Failure Mode

General Shear FailureGeneral Shear FailureVV

BulgeBulge

33 331122 2233 33

Soil undergoes sudden failure as wedge 1 displaces Soil undergoes sudden failure as wedge 1 displaces zones 2 and 3zones 2 and 3

Soil undergoes sudden failure as wedge 1 displaces Soil undergoes sudden failure as wedge 1 displaces zones 2 and 3zones 2 and 3

VVLocal Shear FailureLocal Shear Failure

22 22

1122 2233 33

Tan Ø’ = tan ØTan Ø’ = tan Ø2233 C’ = CC’ = C22

33Soil undergoes compaction in zones 1, 2 and 3Soil undergoes compaction in zones 1, 2 and 3Soil undergoes compaction in zones 1, 2 and 3Soil undergoes compaction in zones 1, 2 and 3

Settlement of FooSettlement of FooZ Sand & Gravel V

Y

P0

Z S d & G

Sand

Soft Clay Z Sand & GΔ

S

Y

Sand

oC PPlogHCS Δ+

oo

oC

Plog

e1S

+=

otings on Clayotings on ClayV

G lGravel

P0

Δ P VS

Soft Clay

0

Sand & GravelSand & Gravel

Y-S

Sand

Soft Clay

Individual Piles Individual Piles

Method of Estimating LMethod of Estimating LMethod of Estimating LMethod of Estimating LggLoad TestLoad TestggD i F lD i F lggDynamic FormulaDynamic FormulaggStatic Analysis Static Analysis

Load CapacityLoad CapacityLoad Capacity Load Capacity

The Fundamental PThe Fundamental P

RhWWEnergyHammer =

WR

RhW

=

=

WWWWhh

SS

Pile Driving FormulaPile Driving Formula

sRResistanceSoilofWork

hWs R

s

RR

Ultimate Bearing Ultimate Bearing Formula Method (Formula Method (

Q =Qu =

Embedded

Length= D

Length

QP = qPAP

Capacity Capacity -- Static Static (Q(Quu = Q= Qpp + Q+ Qss))= Ultimate Bearing= Ultimate Bearing

Capacity

Qs = fAs

f = Unit Frictionalf = Unit Frictional Resistance

AS = Shaft Area S

qP = Unit Bearing Capacity

AP = Area of Point

Construction AspConstruction Asp

Monitoring ConstruMonitoring Constru

Quality Assurance

pectspects

uction Operationsuction Operations

Select Material SpSelect Material Sp

ggSpecification ItemSpecification ItemggSpecification ItemSpecification Item-- 6”6”--8” Lift 8” Lift

ThicknessThickness-- Topsize Topsize

RestrictionRestriction-- Gradation Req’mtGradation Req’mt

pecificationspecifications

ggReason for ItemReason for ItemggReason for ItemReason for Item-- Small Compaction Small Compaction

EquipmentEquipmentq pq p-- Less than 3/4 Lift Less than 3/4 Lift

ThicknessThickness-- CompactibilityCompactibility

*PROJECT *PROJECT

CooperatioCooperatioDesign & CoDesign & CoDesign & CoDesign & Co

SUCCESS*SUCCESS*

on Between on Between onstructiononstructiononstructiononstruction

GENERAL OVERVGENERAL OVERVGEOTECHNICAL GEOTECHNICAL 1 Recognize the Import1 Recognize the Import1. Recognize the Import1. Recognize the Import

Theory, and ExperiencTheory, and Experienc2 Recall Basic Geotech2 Recall Basic Geotech2. Recall Basic Geotech2. Recall Basic Geotech

ACTIVITY:ACTIVITY: QuestionQuestion--

VIEW OF VIEW OF INPUTINPUT

tance of Testingtance of Testingtance of Testing, tance of Testing, cece

hnical Phaseshnical Phaseshnical Phaseshnical Phases

--AnswerAnswer