09 - hydraulic conductivity for students/09... · 2/25/2015 12 example what would be the horizontal...

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Hydraulic Conductivity

Chapter 6

Bernouli’s Equation

piezometer

∆hydraulic gradient

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Flow Regimes

1

kDarcy’s

Law

Seepage Velocity

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Seepage Velocity

1

1

Hydraulic Conductivity

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Hydraulic Conductivity

Degree ofSaturation

Absolute Permeability

Absolute Permeability(Soil Property Only)

Hydraulic Conductivity(Soil / Water Property)

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Source: www.ce.texas.edu

Viscosity of Water

Source: www.ce.texas.edu

Density of Water

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Hydraulic Conductivity

Soil PropertySoil / Water Property

Hydraulic Conductivity

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Constant Head Test

Falling Head Test

2.303 log

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Example

1 

Example

2.303 log

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Example

→

Source: www.ce.texas.edu

Density of Water

25C

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Well Pumping

Well Pumping

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Example

A 200‐mm‐diameter well that fully penetrates a25‐m‐thick confined aquifer is pumped at a rateof 2000 m3/day. The drawdown in an observationwell 100 m away is 1.4 m and the drawdown inan observation well 50 m away is 4 m. What isthe horizontal permeability of the aquifer?

Drawdown

h0 h

s

q

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Example

What would be the horizontal permeability ofthe aquifer if it was unconfined instead? Assumethe static water level in the aquifer is 100 mabove the impervious layer.

Drawdown

h0 = 100 mh

s

q