Báo cáo thực tập: TÍNH TOÁN MÓNG TRỤC 2 ppt

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 
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
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I
š
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I

QI
š
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O4*.F.O)KS../;-1E*.T<8=1iI“*.F./3H67G/5G/d.F.(kG.F.Q8=1.51/d112-67Q-
D?8
K
L'M NNOQ.J(I
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š*
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D.3‡678r12-67cf6/+4G8=1X34*I“*.F.G/…1/-r.O)+0d*8=1O)./*9-KL-I“*.F.
š
*
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e-<
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*
+
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D/*<.5.+4G8=1I).F.8*e-<1/)6/.5.+4GG/L61V.J./*9-X)N/
*
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Dˆ6.SO)08rKL-•
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.5.+4G8=1G/L61V8JR-D?KS-I0%+T'U@%VW8Š1R6/12;
KVI<K51cn6š
*
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+,  /'0%'1$2%*234,5 -Z


 !"#$%!& '()*
z1=2650
z8=14850
z7=13500
z6=11500
z5=9500
z4=8000
z3=6500
z2=4500
500
h=1800
1
25005000
2
3
4
500
13400
l1=1700l3=2000 l2=2000l5=2000 l4=1000l6=2000l8=700 l7=2000
,-./(01

23
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C
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.51 C
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z
AC  A
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A  b AC AC
51/d1Ot<
∞
C  YC AC bC
  C Z A
Z  C YY Yb
b Z AbC ZZY CC

b

 

= Z
=
×
∑
=
CCCA
D >5.8;6/(
/0E67.5./1tIu18=11h6/*n614*I“*.F.ž

zCI2<cE67K5./96J67.T<
Ÿ/L-7F. 6¡K-N2<zAAI
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 s AA Y   CCCAv
:
(⇒ = × × × + × × =
339.3@
⇒
Sức chòu tải cho phép:
¢
A
A
:
:
%
(

(
E
= = =
81.5
‰0K56/G
¢
 sC v s v
[= :
   = ≥ ÷ = ÷
(tho£<v
l=> (/F6

zI*6s
O+
–
86
QvzI*6s–bCvzH3.6.
?-(T/8THU)1V45,C,M'/(T/W(*46'(,C,
DŠ.5..F.R1E6//3i67+•66/<-.J1/Š.0*+).F.8H65..F.cV12R12067Iu1c•67
K<0./0:/0E67.5./.T<.5.1*I.F.<≥XsO4*XDX3‡67:R6/.F.v
- Áp lực tính toán giả đònh tác dụng lên đế đài do phản lực đầu cọc gây ra:
( ) ( )
 
bC
  

E6
(
(
:

= = =
×
100.6(T/m
2
)
-Diện tích sơ bộ của đế đài:

AAY
  b 

ID

D

C
(  
γ
= = =
− × × − × ×
3.54 m
2
.
Trong đó:
+ N
tt
o
: Tổng tải trọng tính toán xác đònh lên đỉnh đài.
+ γ
tb
= 2 T/m

3
. Trọng lượng thể tích bình quân của đài và đất trên đài.
+ n = 1.1: Hệ số vượt tải.
+ h = 1.8: Chiều sâu chôn đế đài
+,  /'0%'1$2%*234,5 -Y

 !"#$%!& '()*
-Trọng lượng của đài:


ID *
<  C 
γ
= × × ×
=1.1 x 3.54x1.8x 2 = 14T
-Số lượng cọc cần thiết
6
.
11
Kc

AAY A

bC

;
E

(
β

+
+
= × = × =
∑
A.F.
&4*(βzD/,KV:*6/67/*,I:Š8U6E6//3i67.T<1E*12F6767<67O)IMI[6
- VPNchọn số cọc chính thức là n
c
= 6
cọc.
- Ta bV12R.F../0Iu1c•678)*IJ67
6/3K<-(
?X(YZF/0:[(Y'+8(Y\4
:]D)^_,
-Diện tích đáy đài thực tế:
F
đ
= 1.6x2.4 =3.84 m
2
.
-Trọng lượng thực tế của đài
G
0
tt
= nF
đ
γh = 1.1x3.84x2x1.8 = 15.2T
-Lực dọc tính toán thực tế xác đònh đến cốt đế đài:
 
  

  <= +
∑
=342.49+15.2 =357.7 T
-Momen tính toán xác đònh tương ứng với trọng tâm diện tích tiết diện các cọc tại
đế đài:
$


+=
= 26.48 +8.44x1.8 = 41.67 Tm
-Lực tác dụng lên các cọc biên:
∑
∑
=
±=





%


\
\


(



I<g

I*6I<gQ
&4*(y

\
I<g
z
E
\
I<g
zY–∑g
*

zAgY

zAI

I<gQI*6
CZZ AZ Y
 A

(
×
= ± =
59.616 ±11.575
P
tt
max
= 59.616 + 11.575= 71.2 T; P

tt
min
= 59.616 -11.575 = 47.88 T
P
tt
tb
=
Z AZbb

+
= 59.46 T
-Trọng lượng tính toán của cọc: P
c
= 0.3 x 0.3 x14x 2.5x1.1=3.465 T
-Điều kiện kiểm tra :
I<g I*6
– 
% 
( ( ( (+ ≤ ≥
-Ta thấy: P
tt
max
+ P
c
= 71.2 + 3.465 =74.5 T < P
TK
=81.5T (th‹<v
P
min
= 47.88 T >0 (th‹<v

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m
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m


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l
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h
m =
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α
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+,  /'0%'1$2%*234,5 -AZ

 !"#$%!& '()*
X
Y
300 500 500 300
1600
300 900 900 300
2400
100 1000
1100
800
900 600 900
600 300
p =142.4 T
6
p
3
+
I
I
IIII
p
2
p
1

+ p =178.84 T
3
+
300300
4
5
°
,-.E&A8* '2F *?@6

@.5.7.J(XYZ7[2
6.3.2.1./ Ta \G
Dh.XF.12-N96g-V6785NIJ67z+h.XF.12067.r1y12F67+3W678):*967y12F67
+3W6713‡67gLN12n68):*967
:E
< =
3456)–
:E
< =
3785)–

< =
4976)
D<.JcE671E*12F676/3K<-(
!
"#
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(

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-/ -."/ -/ -/ -."/ -/
2 bAC C b AZC C ZAb
@.5.7.7.JVA]'
+,  /'0%'1$2%*234,5 -Ab

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DŠ8)*.F.:/M67c;X;././-NŠ6O).r1:/M67c;-V6G/E*8u18)*.F.i8rK<-K<0./08T
67)IO)08=1
D *ŠI12<8*9-:*,6(
 
     
  b
AC Yb AC C ZAb
   
 B B
J   D   $ 

ϕ
γ
   
= × × × − × = × × × − × > =
 ÷  ÷
   
⇒
I
 B≥
20678J(ϕD7J.6r*I<K51.T<+4G8=11t85N8)*12i+n6Qϕzb
0
γDX-6712F67.T<+4G8=11t85N8)*12i+n6QγzYbI

cD.d6/85N8)*1/[0G/3H671/Ž677J.O4*1E*12F676•I67<67Q7*E1/*U1czCI
&PN1<./F6./*9-KL-./M68)*/
I
zbI
@.5.7.5.JT^C_`a%+
y/F6./*9-X)*.F.
.
zAI
yF.67)IO)08)*Is120678JACI+)G/p6.F.c;G/5O™QG/p6.‚6+d*CIv
 y/F61*U1X*,6.F.(g.I
yV1XF..T<.F../F6A—bs"
K
zb.I

v
y‰„X…67.F.I<K51
yd.F.c•67G/3H67G/5GkG1•6/

@.5.7.9.Jb'cVdc$e)G
D‰S../;-1E*.T<.F.g5.8;6/1/[0/<*123‡67/WG(KS../;-1E*.T<.F.1/[08=1696O)
KS../;-1E*1/[0OP1+*,-+)I.F.
 
R6/13H671h6/3IJ6712…."(

O+
zϕgs"
K
g
K
y"
c
g
c
vz≈353.
!"#
$%&'$($)'*'$+'
D=N:U1e-E6/3IJ6712…."(
86
zIgsI

gg"y-
∑
I
š
gš
*
g+
*

vz339.3@
⇒
Sức chòu tải cho phép:
¢
A
A
:
:
%
(
(
E
= = =
81.5
‰0K56/G
¢
 sC v s v
[= :
   = ≥ ÷ = ÷
(tho£<v
l=> (/F6

zI*6s
O+
–
86
QvzI*6s–bCvzbC.
@.5.7.6.JfafVBC+;Tf_
-Diện tích sơ bộ của đế đài:


bAC
  b 

ID

D

C
(  
γ
= = =
− × × − × ×
2.95 m
2
.
Trong đó:
-Trọng lượng của đài:


ID *
<  C 
γ
= × × ×
=1.1 x 2.95x1.8x 2 = 11.68T
-Số lượng cọc cần thiết:
6
.
11
Kc


bAC b

bC

;
E

(
β
+
+
= × = × =
∑
A.F.
+,  /'0%'1$2%*234,5 -AY
300 500 500 300
1600
300 900 900 300
2400

 !"#$%!& '()*
&4*(βzD/,KV:*6/67/*,I:Š8U6E6//3i67.T<1E*12F6767<67O)IMI[6
- VPNchọn số cọc chính thức là n
c
= 5 cọc.
- Ta bV12R.F../0Iu1c•678)*IJ676/3K<-(
@.5.7.@.JKL")a_'Cg.
-Diện tích đáy đài thực tế:
F
đ

= 1.6x2.4 =3.84 m
2
.
-Trọng lượng thực tế của đài
G
0
tt
= nF
đ
γh = 1.1x3.84x2x1.8 = 15.2T
-Lực dọc tính toán thực tế xác đònh đến cốt đế đài:
 
  
  <= +
∑
=284.65+15.2 =299.85 T
-Momen tính toán xác đònh tương ứng với trọng tâm diện tích tiết diện các cọc tại
đế đài:
$


+=
= 26.51 +8.6x1.8 = 42 Tm
-Lực tác dụng lên các cọc biên:
∑
∑
=
±=






%


\
\


(


I<g

I*6I<gQ
&4*(y

\
I<g
z
E
\
I<g
zY–∑g
*

zAgY

zAI


I<gQI*6
YYbC A Y
C A

(
×
= ± =
59.97 ±11.66
P
tt
max
= 59.97 + 11.66= 71.63 T; P
tt
min
= 59.97 -11.66 = 48.3 T
P
tt
tb
=
Z AZbb

+
= 59.46 T
-Trọng lượng tính toán của cọc: P
c
= 0.3 x 0.3 x14x 2.5x1.1=3.465 T
-Điều kiện kiểm tra :
I<g I*6
– 

% 
( ( ( (+ ≤ ≥
-Ta thấy: P
tt
max
+ P
c
= 71.63 + 3.465 =75 T < P
TK
=81.5T (th‹<v
P
min
= 48.3 T >0 (th‹<v
=> /0EI•68*9-:*,6+h.15.X…67+n6.F../;-6k66/*9-6/=115.X…67g-V67.F.
c*n6O):/M67.J.F.c;:k0X08J:/M67.p6:*ŠI12<8*9-:*,6./V676/q
6.3.2.7./ %&'h&=fD
IJKL")+MND"OP"Q
D=N:U1e-EIJ6712…."(

 ¢
A C¢
 
A A
*
ϕ
α
= = =
D/*9-X)*Q2r67:/V*IJ67e-N34.(

zCI–


zAI–

zCI
DR6/12F67+3W67:/V*IJ67e-N34.(

%
:
%
%;%
%
:
%
<<<< ++=

 D2F67+3W67G/dIO*1t8U8)*12i+n6(
%
:
<
zZCb
D2F67+3W67.F.(
%
%;%
<
zCg
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zDDZACzDZC

s v
 ' 
 
    6= + +
∑ ∑
zsAYDACvysZACgZDgZvzDCACI

s v
 ' 
$ $ $= +
∑
zZbDZzD

ZC
CCAAb
C
%
 = =
∑
–

CAC
AAZ
C
%
 B= =
∑

–



C
%
$ = − = −
∑
@.5.5.7.JVA]'Gs7*V67IJ6712…."v
/F6./*9-KL-./M68)*/
I
zbI
@.5.5.5.JT^C_`a%+Gs7*V67IJ6712…."v
@.5.5.9.Jb'cVdc$e)(s7*V67IJ6712…."v
 (
O+
z353.
!"#
:
( =
339.3@
+,  /'0%'1$2%*234,5 -C

 !"#$%!& '()*
⇒
Sức chòu tải cho phép:
¢
A
A
:

:
%
(
(
E
= = =
81.5
l=> (/F6

zI*6s
O+
–
¤
86
QvzI*6s–bCvzbC.
@.5.5.6.JfafVBC+;Tf_
-Diện tích sơ bộ của đế đài:

ZC

  b 

ID

D

C
(  
γ
= = =

− × × − × ×
m
2
.
-Trọng lượng của đài:


ID *
<  C 
γ
= × × ×
=1.1 x 6.6x1.8x 2 = 26.14T
-Số lượng cọc cần thiết
6
.
11
Kc

ZC A

bC

;
E

(
β
+
+
= × = × =

∑
YZZ.F.
&4*(βzD/,KV:*6/67/*,I:Š8U6E6//3i67.T<1E*12F6767<67O)IMI[6
- VPNchọn số cọc chính thức là n
c
= 10 cọc.
- Ta bV12R.F../0Iu1c•678)*IJ676/3K<-(
300 1200 300
1800
300 500 1000 300
4600
1000500 500500
P[f *-AB%@% %*L'
@.5.5.@.JKL")a_'Cg.
-Diện tích đáy đài thực tế:
F
đ
= 1.8x4.6 =8.28 m
2
.
-Trọng lượng thực tế của đài
G
0
tt
= nF
đ
γh = 1.1x8.28x2x1.8 = 32.79T
-Lực dọc tính toán thực tế xác đònh đến cốt đế đài:
 
  

  <= +
∑
=637.65+32.79 =670.44 T
-Momen tính toán xác đònh tương ứng với trọng tâm diện tích tiết diện các cọc tại
đế đài:
$


+=
= 5.145 +0.13x1.8 = 5.377 Tm
+,  /'0%'1$2%*234,5 -CA