coefficient of permeability

7/24/2019 Coefficient of Permeability

1/10

Typical Coefcient o Permeability k Values or Dierent Soils

Relative PermeabilityCoefceint o Permeability

Tyoical Soilsk, (cm/sec)

Very permeable Coarse gravel

Medium permeable Sand, fne sand

Low permeable Silty sand, dirty sand

Very low permeable Silt, fne sandstone

Impervious Clay

Ishibashi, I. and Hazaria, H. !"##. Soil Me$hani$s %undamentas.

C&C 'ress (aylor ) %ran$is *roup, +S.

HAZE!S "#R$%&A (''')

-idely used or saturaed sandy soils.

k

where, k $oe/$eint o permeability 0$m1se$2

parti$el size or whi$h #"3 o soil is fner 0mm2

C Hazen4s empiri$al $oe/$eint, whi$h taes a value between ".5 and #

0mostly ".5 to #.62, depending on literatures 0Carrier !""72, with the

average value o #."

8e$ause o the wide range o C values, this e9uation shall be used only as a rough estimate o .

"."7"" mm

C #."

k *++E+- cm/sec

:otes;

#.

!.

< # = #">#

# = #">#to # = #">7

# = #">7to # = #">6

# = #">6to # = #">?

@ # = #">?

C.('+

)0

'+

Input parametrs marked inpurple:

'+

*enerally limited to ".# mm @ A#"

@ 7 mm 0Hazen #B!, ###D Holz and Eova$s #B

(he Hazen empiri$al $oe/$eint $orresponds to a water temperature o #"FC.


2/10

Approximate Coefcient o Permeability

Ty1e o San2 (%SCS)Coefceint o

k, (c

Sandy Silt "."""6

Silty Sand ".""!

Very %ine Sand ".""6

%ine Sand "."!

%ine to Medium Sand "."6

Medium Sand ".# t

Medium to Coarse Sand ".#6

Coarse Sand and *ravel ".!

+.S. rmy Corps o Gngineers

"."

#D Coduto #2


3/10

Typical Coefcient o Permeability k Values or Dierent Soils


Tyoical Soilsk, (cm/sec)

Very permeable Coarse gravel

Medium permeable Sand, fne sand

Low permeable Silty sand, dirty sand

Very low permeable Silt, fne sandstone

Impervious Clay

Ishibashi, I. and Hazaria, H. !"##. Soil Me$hani$s %undamentas.

C&C 'ress (aylor ) %ran$is *roup, +S.

CHAP%3S!S "#R$%&A (0++-)

k

where, k $oe/$eint o permeability 0$m1se$2parti$el size or whi$h #"3 o soil is fner 0mm2

e void ratio o soil 0volume o voids 1 volume o solid parti$les2

an!es o "oid ratio# e $%ra&a# '( DAS: Principles o )oundation *n!ineerin!+

Soil Ty1e e

'oorly graded sand with loose density ".B

-ell>graded dense sand ".56

Loose density sand w angular parti$les ".6

Aense density sand w angular parti$les ".5

Sti $lay ".

Sot $lay ". > #.5Loess ".

Sot organi$ $lay !.6 > 7.!

*la$ial till ".7

"."#"" mm

e ".56

k 0*+E+- cm/sec

< # = #">#

# = #">#to # = #">7

# = #">7to # = #">6

# = #">6to # = #">?

@ # = #">?

0*-400.5('+

)0.(e6/('7e))8+*9:0;

'+


'+


4/10

Approximate Coefcient o Permeab

y1e o San2 (%SCS)Coefceint o

k, (c

Sandy Silt "."""6

Silty Sand ".""!

Very %ine Sand ".""6

%ine Sand "."!

%ine to Medium Sand "."6

Medium Sand ".# t

Medium to Coarse San ".#6

Coarse Sand and *rav ".!

+.S. rmy Corps o Gngineers


5/10

Typical Coefcient o Permeability k Values or Dierent Soils Approxima


Tyoical Soils Ty1e ok, (cm/sec)

Very permeable Coarse gravel Sandy Silt

Medium permeable Sand, fne sand Silty Sand

Low permeable Silty sand, dirty sand Very %ine S

Very low permeable Silt, fne sandstone %ine SandImpervious Clay %ine to Med

Medium Sa

Ishibashi, I. and Hazaria, H. !"##. Soil Me$hani$s %undamentas. Medium to

C&C 'ress (aylor ) %ran$is *roup, +S. Coarse San


6/10

It $an be shown that, ssuming the parti$le size distrib

ea$h pair o sieve sizes.

0#1Ai2

aveK # 1 0A

l,i".5"5JA

s,i".662


7/10

k

:otes;

e ".6" k '*--E+; cm/sec

S" ?.6

Soil Ty1e Sand, some silt, tra$e to some $lay

Sie CImIlative

(mm) Passin () ()

C#ARSES3EJ3K

?6 #""

7 #"" "."" .?5?77 ".""

67 #"" "."" 6.?7B5B5 ".""

7?.6 #"" "."" 5.7"B#75 ".""

!.6 #"" "."" 7."5"?"7 ".""

# .# 7." !.#?#56 #.B"

#7.! .# "."" #.6!BB!6 ".""

.6 5.? #.5" #."B6"# #.!

5.?6 !. !.#" ".!B?56 7.75

! B. !.?" ".!B5## .6"

".B6 BB.? #.!" ".#!"7B7 .?

".5!6 B?.? #."" "."65#!? #?.?7

".!6 B5.B !." "."7#"# 7.!?

".#" 75.7 6".6" "."#6""" 7767.!

"."?6 !7.6 #".B" ".""B?7 #!5."

H=/R#$ETER

"."5? #6.! B.7" ".""6B66 #56.B

"."776 #7.6 #.?" ".""7B67# 55#.!#

"."!#5 ##. #." ".""!6B" !"."!

"."#!6 #".! #.?" ".""#67? #"B?.#B

".""B .7 "." ".""#"!B# B?6.7

".""7 B.6 ".B" "."""?!? #".7"

".""7# .B #.?" "."""5#! 5"B5.6

".""#7 6.# #.?" "."""#B7 #!7.#"

"."""! " 6.#" ".""""57# ##B5#.??

'-'-6*4

('*4 '+-).5'++ / FD(i/(

l,i+*-+-.

s,i+*;;G80.('/S"0).5e6/('7e)8


i

(l,i

+*-+-.s,i

+*;;) i/ (

l,i+*-+-.

s,i+*;;)

D(i/

av i)

10000

10

20

30

40

50

60

70

80

90

100

PERCENTFINE

R

THAN


8/10

a&a# '( DAS: Principles o )oundation *n!ineerin!+

e

ose density ".B

".56

gular parti$les ".6

gular parti$les ".5

".

". > #.5

".

!.6 > 7.!

".7


9/10


10/10

ill wor or non>plasti$ silts.

has long, Pat tail in the

stimated in order to

0.00010.0010.010.1

coefficient of permeability

Documents