coefficient of permeability
TRANSCRIPT
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7/24/2019 Coefficient of Permeability
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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 $orresponds to a water temperature o #"FC.
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Approximate Coefcient o Permeability
Ty1e o San2 (%SCS)Coefceint o
k, (c
Sandy Silt "."""6
Silty Sand ".""!
Very %ine Sand ".""6
%ine Sand "."!
%ine to Medium Sand "."6
Medium Sand ".# t
Medium to Coarse Sand ".#6
Coarse Sand and *ravel ".!
+.S. rmy Corps o Gngineers
"."
#D Coduto #2
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Typical Coefcient o Permeability k Values or Dierent Soils
Relative PermeabilityCoefceint o Permeability
Tyoical Soilsk, (cm/sec)
Very permeable Coarse gravel
Medium permeable Sand, fne sand
Low permeable Silty sand, dirty sand
Very low permeable Silt, fne sandstone
Impervious Clay
Ishibashi, I. and Hazaria, H. !"##. Soil Me$hani$s %undamentas.
C&C 'ress (aylor ) %ran$is *roup, +S.
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;
'+
Input parametrs marked inpurple:
'+
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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
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Typical Coefcient o Permeability k Values or Dierent Soils Approxima
Relative PermeabilityCoefceint o Permeability
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
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It $an be shown that, ssuming the parti$le size distrib
ea$h pair o sieve sizes.
0#1Ai2
aveK # 1 0A
l,i".5"5JA
s,i".662
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k
:otes;
e ".6" k '*--E+; cm/sec
S" ?.6
Soil Ty1e Sand, some silt, tra$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
Input parametrs marked inpurple:
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
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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
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ill wor or non>plasti$ silts.
has long, Pat tail in the
stimated in order to
0.00010.0010.010.1