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Thiết kế môn học nền và móng pptx

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 


 !"#$%&
 !"#$%&'()'()⇒

*+,-"
. /0"1()23,!4!0%5%678
*9

:
;<
*=>?9+>-.->@*AB>C"
. /0"1!0D23,!4!0%5%678
*9->?*AE>-9-,?*AE>?"
 !0%5%678*9AB>C"
!0%5%6FG2H3*9C>-"
!0%5%IFG*H:
F
*C> C>-*9->-"
<)!0J78*AB>C:C>-*AE>C"
*+,
)-!!./01234(56(./0!738
2.1. Tải trọng bản thân của KCPT và các bộ phận khác (DC
1
)
!3 9./7:
KLM<:NOIP?A
 
;<=>7?@A>?@>7?@B>C?@@D
EF


70%4 K2Q3<G"RS!Q"T*C"
C
*C>A-
B
""
C
U23<)QV<&P*=-"*=>A-
E
""
2Q3W;5PQ"T*C
γ
2F37XYZF[(*C? \"
@
A*C>A-
B
]=>A-
E
]C]C? ]+>^A]A-
.+
*B^B= 23
2.2. Trọng lượng lớp phủ và lan can (DW)
_*2_
A
9_
C
3
_
A
7XYT!XPF[0`WP!X
_

C
7XYT!XPPF[(XJa>
_*+,^A{-,-?]=-]2AE,^:-,?3]C@ 9C]A ]=-}
*ACBBBA^23
2.3. Hoạt tải (LL) và tải trọng bộ hành (nếu có)
Kb%c]dPM<<!VI7NYPW!
Ae/M<<dd2UU39M<7XV<dd2+>@\"3
Ce/!<782UU39M<7XV<dd2+>@\"3
@+-f]2-C]/M<<dd2UU392CXV3M<7XV<dd+>@\"3

U
*"]]UU
70%4
UU*"!]2UU
A
,UU
C
,UU
@
3
=G"H@I(-J.//I$I
KLM<:NOIP?A
 
* Trường hợp 1:2UU
A
3A]/<dd9M<7XV
UU
A
*AE?2A9g
A

39@?>g
C
9
C
@,+ xL
+E,-
=-
@,E.=-
A
A
==
Y
^==,-
=-
@,E.@,E.=-
A
C
==
Y

UU
A
*B@=E+?23
* Trường hợp 2 (LL
2
)A]/C789M<7XV
UU
C
*AA-2A9g39
C

@,+ xL
?E@BA-
+^@,-
=-
C,A.=-
A
C
A
=⇒
==
LL
Y
KLM<:NOIP?A
 
* Trường hợp 3 (LL
3
)-,+2C]/M<9M<7XV3
UU
@
*-,+hAE?2A9g
A
9g
E
9g
?
39@?2g
C
9g
@
39+,@>Ui

g
A
*
+E,-
=-
@,E=-
=
g
C
*
^==,-
=-
@,E.@,E.=-
=
g
@
*
=^B,-
=-
A?.=-
=
g
E
*
=CE,-
=-
@,E.A?.=-
=
g
?

*
BB@,-
=-
@,EC].A?.=-
=

UU
@
*A-=CE?^23
,KC.-J./%L,
M<7 O< g< O<]g<
e/M<<d
d
AE? A AE?
AE? -,+E A@B,@
@? -,^== @-,=
'j*`]"] AB?=E^=
e/!<78
AA- A AA-
AA- -,+^@ A-^
'j*H]"] AEA@@^B
C]/M<<d
d
AE? A AE?
AE? -,+E A@B,B
@? -,^== @-,=
@? -,=^B C=,?A
AE? -,=CE A-E>+^
AE? -,BB@ +B>A@?
'j*]"] CB?^A@-

M<7
XV
+,@ ->?]UW2UW3 *+>@]->?]UW]"]*
C=^^E
KLM<:NOIP?A
 
k*+>@]UW]"]*AB+C>B
UU
"!]
*UU
@


UU*UU
@
*A-=CE^-23



U
*->B?]E]A-=C>E^*C=^^E 23
2.4. Lực hãm xe (BR)
Hl*-,C?2AE?]C9@?3]"]
< "*-,B?2mn@3
*E
Hl*CAAC?-23
I!%o%;<m<%IFGQ
Hl
*AB>C9->@9C>C*A^>=2"3
2.5. Tính tải trọng bản thân của trụ (DC

2
)
 <!78VCP
.O"78*?CC-2""3
.OJ78,!*:?CC-*AEC ?CC-*^+^-2""3
OJ78aP70XV?? 2""32/0"10)
Vp"*=>?"3
*+70:M

"
*^,=B?>A-
A-
2""
@
3


"
*^=,B?2"
@
3
KLM<:NOIP?A
 

J
*2?A ]@ :A ]A ]C3]^+^-
*A>A+]A-
AA
2""
@

3

*C-B,B?2"
@
3

C
*>
γ
F[(]+,^A*?-B^-+A23
2.6. Tải trọng nước (WA)
- Lực đẩy nổi
_
`
*A ]+,^A22?A ]@ :A >A >C3]?? 9AAC ]^C ]C 3>A-
.+
*C?A+?-C>@23
.qPX1QoMQ/0dDPQ<
2Q3GW;MT!78*A>E2m%78m(3
a;<dd,/0X<dd2"\W3
P*?,AE>A-
.E
>
Q
>
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1.1 Chọn cao độ mũi cọc
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1.2 Chiều dài cọc
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1.3 Mặt cắt ngang
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C> =N#./70O,0"G
KLM<:NOIP?A
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C>A Theo vật liệu
Chọn vật liệu làm cọc như sau:
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Công thức tính toán:
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l
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2 3 2 3c gr gr c gr d
V Q Q Q
≤ = +


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723
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KLM<:NOIP?A
 

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x50.7) +10500x 6000 x10.125 x0.25x 10-3 =217414 (kN)
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2 3 2 3c gr gr c gr d
V Q Q Q≤ = +
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Điều kiện : u
max
≤ 38 mm
( Theo tiêu chuẩn thiết kế 22TCN-272-05 phần nền và móng )
Sử dụng chương trình FB – PIER V4 ta tính được
*********************************************
***** Final Maximums for all load cases *****
***** PIER # 1 *****
*********************************************
Result Type Value Load Comb. Pile
*** Maximum pile head displacements ***
Max displacement in axial 0.4056E-02 M 1 0 5
Max displacement in x 0.1441E-01 M 1 0 1
Max displacement in y -0.1669E-06 M 1 0 6
Ta thấy chuyển vi ngang ở đầu cọc lớn nhất:
- Theo phương x: U
xmax
= 0.01441 m = 14.41 mm <
38mm => Đạt
- Theo phương y: U

ymax
= -0.1669 x10
-6
m = 0.1669 x10
-3
mm < 38mm => Đạt
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