
A. PHẦN LÝ THUYẾT
BÀI 1:
THÍ NGHIỆM XÁC ĐỊNH ĐỘ ẨM TỰ NHIÊN
 !""#$%&'$%()*+,)**-
1. Mục đích
./012#3&4"560!7
2. Thiết bị thí nghiệm
'89":;2/0<=>=)7
3?5@"A2<==

'7
B&4"7
'CDEF"G H2;I:7
JKL#;M&'&'N7
O;8NP)7
'C?MQ..?M;R"E& ?"7
B&ST57
3. Các bước thí nghiệm
3.1 Chuẩn bị mẫu thử
S/012#3&5UV4"3;8CN8 W)-7' 4"5
Q. CD3&EF;I:>X0?C>/018CN
YZQ.X?587[&";&;:IQ.!89":S
/018CN3&2Q4"57
3.2 Cách tiến hành
\6I2;M&4"Q.?5WI 3?5<8CN8
]7%2?5,CQ5N ?^Q.0

_)=`a`

'>CQ5M&& Q.

 ;,
o,2#3&5YdZ7
o
)
,8CN3&2Q.4"5YZ7
o
`
,BCN2Q.4"5X?5YZ7
o
'
,8CN27
Ghi chú:Thí nghiệm này được thực hiện lặp lại hai lần để xác định giá trị trung
bình7
%"l$mn ` \[[$=e-))`===`
JW),B<f"W2#3&5

BÀI 2:
THÍ NGHIỆM XÁC ĐỊNH DUNG TRỌNG TỰ NHIÊN
 !""#$%&'$%(`=`,)**-
1. Mục đích
.S/01U"!3&57"
!N.8CN3&2TQ1S5!7
2. Thiết bị thí nghiệm
& Qp>& `>8+7
'k>2/0=>=)7
8q7
r&"G7
3. Các bước thí nghiệm
V8q/018 Q.8 .>@"& 3&
U& Qp>S3&U& Qp7

BÀI 3:
THÍ NGHIỆM XÁC ĐỊNH GIỚI HẠN CHẢY, GIỚI HẠN DẺO
 !""#$%&'$%()*x,)**-
1. Mục đích

01X o


01Uy o
z
2. Cơ sở lý thuyết
wUg 3&5TMQ2#.5N ?^;8<5"E10 
"Si0M?&0Ug 7wUg oHEF2
#YdZ3&5?&"8X. 2@"QQ.Nm.f";8>
Kf"EIR"MQ.M.0 I;@"U.8 W{)=7
wW'&?&&U3&5N.2#E25. >/01EF
Uhhf"&:'&?&&U>8X58) R)`7x?&"`-0
:
3. Thiết bị thí nghiệm
o
hh'&?&&U
o
& IX
o
B0(=/+=
o
O;8NP)
o
'C?MQ..E& ?"
o

12#7
'M<hQN&] @"mN!701
5NR/012#MQ?C0:i)`{-
'mMQ. ?CN">Qyh"MQ2#>h .N &
ES"Ul?CNR:7}"&b&LN.s72#MQ?C0:N.
`-N.W'&?&&U
%"l$mn - \[[$=e-))`===`

b. Xác định giới hạn dẻo
[kUhR5pN3&KX 7
5)5Q.N5Hs NpE.& H0R";&Nmq
.!80 <8.f";8EF7
%<"Q8;>f"5Q4pbN!8<Q.Ug >KQ;
.pQ.<hNm<88EIR"MQ.X.
b&DU.{)=7
%H0 f"Qi&M>EDQ. 2:IN 58DE187
%&?&"85 2CS")=><./012#3&5
 2YdZQ2/0<=>)d7
CQP4"5>W<.8T`NR? ? 
S/01Ug 7
501"EK2&NRN.Ug 3&4"57
[&N ^Q@2# 0NR/01? ? ~`d7
5. Tính toán kết quả thí nghiệm
5.1 Kết quả thí nghiệm giới hạn chảy theo Casagrande
wW3&5 '&?&&UocW/01EFf"WU
mEFo

7}"&boQ.o

<N: M,

11.52 23.12 20.22 33.33 33.33
PL-2
1B 11.96 15.32 14.6 27.27 23.71
5 11.93 15.03 14.51 20.16
PL-3
32 6.55 12.4 11.65 14.71 14.80
47 6.59 12.07 11.36 14.88
%"l$mn + \[[$=e-))`===`

BÀI 4:
THÍ NGHIỆM CẮT TRỰC TIẾP
 !""#$%&'$%()**,)**-
1. Mục đích
01;2&?0ϕQ.NUYI&8 0Z7
2. Thiết bị thí nghiệm
2.1 Máy cắt trực tiếp
 8S""@Nf"&QVME<Q.f"&0&pYU X[ N?{
n?W/"5Z7'0E2:3&0|,
•2'&?&&U,M&4"57
•$p 0N, ?M1"I3&57
2.2 Dụng cụ
J& |,U& >55>8 >Q&?N>gN&">&"M&?>E&W|
0>89":>8q>8s-=/-=>U& QpQ0?C,
•'@"& ,`
•8 ,+7)
•,)7)x`
`
•N,)=x7 
•SM&,+`7((


 Y1?C3&Qp0NZi1?CQ.?&"8f"&1?C7
τ_'7O
4. Tính toán kết quả:
iEW?CN":L&?yM?"5IτTMQi
50Np7
<.QyES"|f"&b&M?"5ItTMQi50Np
S/01;&?0 ϕQ.NUc7
5. Kết quả thí nghiệm
B<f"W '$%()**,)**-
Mẫu thử - Specimen Mẫu thử
1
Mẫu thử 2 Mẫu thử
3
First Trial Second
Trial
Third
Trial
Ban đầu Initial Độ ẩm - Moisture Content, % 74.2 74.2 74.2
Dung trọng ướt - Wet Density, g/cm
3
1.52 1.52 1.52
Dung trọng khô - Dry Density, g/cm
3
0.87 0.87 0.87
Giai đoạn cắt Shear
Stage
Ứng suất chính - Normal stress,
kG/cm
2
0.2 0.4 0.6

α
01?CC8<'
Q

01 U"N]E<U
2. Dụng cụ thí nghiệm
•hhC8<
•hh4",2>&EFU.>U&
•hhH4"kQ.2M&
•'89":2/0=7=)
•p?5)=-

'<))=

'
•2"
•
3. Trình tự tiến hành thí nghiệm
)754"5k,N58C5EF0UVCN54"57€8"Q.
8C5S;4"58+7`-Q.& `7-7
`75m4"5Di)={)-S/012M&7
7V&U. HU& SEFH!Q.U4"57
(7H4"0E60XQ. 02Q.]N!& 8D
<0E7
-7H4"kQ.QpM&N!!<0EQi&;?&";#:H
Qp& ?">0E>N!!4"57
%"l$mn )= \[[$=e-))`===`

+7$HHCIQ. 0Q.SQ. 0CQ.QpM&7
x7H2M&;4"kQ. UhhC8<7

4.2 Vẽ đường cong nén theo thời gian e - logp
•01A?C^'

>A?C6'?
•01?C5B
•010N@C8< 5?^

7
4.3 Tính hệ số cố kết C
v
theo hai phương pháp
?CC8< TsMY'
Q
Z/01 &T0
,
Y&ZzT0&N &pN.T07
YEZzT0'&?&&U&pN.T0N YZ7
zT0'&?&&US/01?C'
Q
TMQ2C8<-=dQ.T
0&N UVS/01?C'
Q
TMQ2C8<*=d7
a. Phương pháp Casagrande
%<"?kUhT0'&?&&UK?C|| "SQ1ES"
Ul!|1 N YZ7'5"L'&?&&U80UhQ.Q/01'
Q

%"l$mn )) \[[$=e-))`===`


Q
_=7)*x
j@"U.5>

-=
{&R<S<2C8<-=d>L
b. Phương pháp Taylor
 T0&N >?C|| "SQ1: ?"C
f"0KC8<Q.Qy!|1 mE:&&(Hình 7-3). R"3&|
1N. sC8<57B^ U.R"<3& R"|1Ih"
SE<UU
=
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&U2s;2UC5)7)-NR2UC
3& sC8<5Y? Qh"Z7w& S3&sU
Q:Q^ &?y &S;2E<UU
*=
XC8<*=d>M
Q;&;
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Kết quả thí nghiệm
 !""#n[\`(-j`===7
%"l$mn ) \[[$=e-))`===`

B. PHẦN THỰC HÀNH
BÀI 1 THÍ NGHIỆM XÁC ĐỊNH ĐỘ ẨM TỰ NHIÊN
[CNR

BCN2
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BCN2
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d)==7
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=
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−
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−
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WW
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
Bài 2 THÍ NGHIỆM XÁC ĐỊNH DUNG TRỌNG TỰ NHIÊN
[CNR
BCNU&
Qp>w
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γ
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γ
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w
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mm
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−
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Giới hạn dẻo :
[CNR

BCN2
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BCN2
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8>
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)e>`*-x>-*
=
−
−
=
−
−
=
PL
P
WW
WW
B

%"l$mn )x \[[$=e-))`===`
%

⇒
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Bài 4 THÍ NHGIỆM CẮT TRỰC TIẾP
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⇒
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τ
_=>`(8v
`
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mm
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hn
mm
mm
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2. Trọng lượng thể tích trước khi thí nghiệm :
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BCN
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=
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mm
mm
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n
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γ
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n
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xe>`7-x>-*
)==7
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z_=>`-
⇒
mmMrrh
nnn
*`>===*`>=
=
=−−=∆−−=∆
z_=>-
⇒
mmMrrh
nnn
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=
=−−=∆−−=∆
z_)
⇒
mmMrrh
nnn
(+>`==(+>`
=
=−−=∆−−=∆
z_`
⇒
mmMrrh
nnn
xx>==xx>
=
=−−=∆−−=∆
z_(
⇒

∆
=∆ e
h
h
e
n
n
⇒
-x+(>))``+>=++>)
=
=−=∆−=
nn
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⇒
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`=
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Z)Y
=
=
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h
h
e
n
n

⇒
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`=
xx>
Z)Y
=
=
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∆
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h
h
e
n
n
⇒
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=
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nn
eee
z_(
⇒

+*)+>=Z++>))Y
`=
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Z)Y
=

Y
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v?Z
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
⇒
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
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*=
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t
H
C
v
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
⇒
_)

*=
,&62^UR*=d2^ .E23&4"57
Hệ số thấm,
ZvY


`
) nn
tb
ee
e
+
=
−

zY8v

Z =>`- =>- ) ` (
ZYmmh
n
∆
mm*`>=
mm(*>)
mm(+>`
mmxx>
mm`>-
Z)Y
=
=
e
h
h
e
n
n

`
) nn
tb
ee
e
+
=
−
-x+(>)
)>(**x- )>*x`- )>`(-x=- )>=+(*-
-=
`
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t
H
C
v
=
Y
`
v?Z
(>)7)=
{(
ZvY
)
77
scm
e
aC
K

{-
ZvY
)
77
scm
e
aC
K
tb
nv
P
+
=
ρ
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{)
)>)e7)=
{)
)>`7)=
{)
)>)7)=
{)
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{)
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'
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Phương pháp Casagrande
Phương pháp Taylor
%"l$mn `- \[[$=e-))`===`