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Applications of Strength Analysis

Earth Slopes

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Applications of Strength Analysis

Structural Foundations

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Applications of Strength Analysis

Retaining Wall

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Applications of Strength Analysis

Tunnel Linings

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Applications of Strength Analysis

Pavement Design

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Direct Shear Test

Pavement Design

Shear Box &Specimen Ring

ShearLoad

Normal

LoadTest Control

&Data

Acquisition

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N Normal Load

T

Shear Load

Internal Diameter

Plan area, A = x r

2

Normal stress,n= N/ A

Shear stress, = T/ A

Shear Box Schematic

Reaction Arm

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Shear Stress vs. Horizontal Displacement (Strain)

0

10

20

30

40

50

60

70

0 0.05 0.1 0.15 0.2 0.25 0.3

ShearStress(psi)

Horizontal Displacement (in)

10 psi

50 psi

90 psi

Peak Strength

Residual Strength

Dense Sand

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0

10

20

30

40

50

60

70

80

0 10 20 30 40 50 60 70 80 90 100

(

psi)

(psi)

Peak Residual Linear (Peak) Linear (Residual)

r

p

Shear Stress vs. Normal Stress (Peak & Residual)

Dense Sand

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0

10

20

30

40

50

60

70

80

0 10 20 30 40 50 60 70 80 90 100

(

psi)

(psi)

Peak Linear (Peak)

Mohrs Circle

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H vs. Horizontal Displacement (Strain)

y

x

Dense sands

Loose sands

any behaviour

in between

Contraction

Dilation

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-0.035

-0.03

-0.025

-0.02

-0.015

-0.01

-0.005

7E-17

0.005

0.01

0.015

0.02

0.025

0.03

0.035

0 0.05 0.1 0.15 0.2 0.25 0.3

H

(in)

Horizontal Displacement (in)

10 psi

50 psi

90 psi

H vs. Horizontal Displacement (Strain)

Contraction

Dilation

Dense Sand

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Void Ratio(e) vs. Horizontal Displacement (Strain)

Initially Loose Soil

Initially Dense Soil

Critical

Void RatioVoidRatio,e

H V d eCalculation Steps

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Index of Required Plots

Shear Stress vs. Horizontal Displacement

Shear Stress vs. Normal Stress (Peak & Residual)

Mohrs Circle (Peak Only)

H vs. Horizontal Displacement

Void Ratio (e) vs. Horizontal Displacement

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Grain Shape &

Holtz & Kovacs

Rounded 30 - 35o

Sub-angular 34-39o Angular 36-41o

Sub-rounded 32 - 37o

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Tips

Post PROCESSED data (not raw) data on blackboard group shear strength ofsand/glass by end of tomorrow.

Note the spot on the blackboard is : CIE 337 Merged Fall 2012==>>LabGroups===> Direct Shear.===> File Exchange

The completed table at the end of the manual of Lab 7 (Page 72) should also

be uploaded. Please put all in ONE file Plot your own data alongside data from ONE other group that used the other

material. You are comparing the shear strength of Ottawa Sand vs crushedglass.

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Lab Procedure Key Points

Fill & levelsand tobottom ofmarking inspecimen box

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Lab Terminology

SpecimenBox

Spacer TopCap

LoadSeat

PorousStone

ReactionArm