Xác định mối quan hệ giữa các thông số động lực học của hệ rung làm tăng độ bền, độ chống thấm của máng xi măng lưới thép (tóm tắt)





C BÌNH









Chuyên ngành: 
 : 62 52 01 01








2014

- V


ng dn khoa hc:

PGS.TS Trn

Phn bin 1: GS.TSKH Ph

Phn bin 2: GS.TSKH Nguyn Tin Khiêm

Phn bin 3: PGS.TS Nguyn Thái Chung

Lun án s c bo v c Hng chm lun án cp Vin
hp ti Vic- Vin hàn lâm khoa hc và công ngh Vit Nam
Vào hi gi 



Có thể tìm hiểu luận án tại:
- 
- V m
1


          
-

   
  - 

             

 l


- 

   
 

             
.
- 

- 
 



, 
    
  
2

t và hai
 
 

-      

 



-    

       
      


  
kênh, 

    
nâng 


  





3

 
1.1. Kt cu XMLT v mng
 


1.3.1 Khái quát chung. 
             

      





a) b) c) d) e)
Hình 1.4 Các dng mt ct ngang thân máng
        

1.3.3 

 

1.3.4 Phân tích v  chng thm ca cu máng XMLT

              
ngoài.
4

            
14TCN 63-2002.
1.4. Mt s công ngh ch to kênh, cu máng XMLT
1.4.1 Ch to bng th công.
.
.

 
   
     
  gia




tông. 






   . Có h       



              


5

    
chia làm 3 h


bê 


      

2
.f
3



 
  c- khác nhau.


tông: 
.  
. 
  
tông 


máng XMLT



o
+ m
1
)
y
+ b
y
y
+ C
y
y
= F
a


6

C
b
Y
Y
Y
o
2
3
1



1-Bàn rung; 2- u gây
rung; 3-   
ng OY.
  
0
    ch
tâm, kg; m
1
-   

0
), kg; C
y
 T
ng

OY, N/m; b
y
     
        


 m
0
+ m
1


2
2 cos
a
y oy
F
y h y y t
M

  
(1.8)



a
= m
o

2


oy
=
M
C
y

-ng riêng, 1/s; h
y
=
M
b
y
2
-

0
yy
;
0
yy

sau:

y
=
y
ht
e


( y
0
cos

1
t +
00
1
y
y h y



1
t ) 

   
 
 
 
2 2 2 2
0 1 0 1
1
2
2 2 2 2
0
2
2 2 2 2
0
cos sin

4
cos
4
y
ht
y
a y y
yy
ay
yy
h
F e t t
Mh
Ft
Mh
     

  

  


  











(1.9)

22
10yy
h



y
ht
e

.
7

        
sau:
 
cos
ay
y y t



(1.10)

y


-

 
2
0
2
2 2 2 2
4
a
oy y
mr
y
Mh

  


(1.11)

 
22
0
2
y
y
y
h
tg







(1.12)




          theo các 

            
 và 
    


Các tài






 

8

C
MÁY 

ÁNG XMLT
2.1. 
.


nhau
ng 

 
.
 M c
x
và V
y

sát XOY T
y
/V
x
. Khi

Mt phng ma sát
XOY
V
x
>> V
y
thì  
/
yx

tg V V



os 1,sinc
  


c:
T
x
= -
y
= - , suy ra là
T
x
-T và
T
y
- T= -T V
y
/V
x


x

y
 V
y

/V
x


thì s ma sát T
y

làm    

9



 
2.2. Mô hình và p
tâm

1
4
3
2
X
Y
o
Y
Y
Cx
C
b
bx

Hình 2.2. 
1.Bàn
ng 4.Lò xo ngang
2. 
2
0 1 x x 0
2
0 1 y y 0
(m m )x b .x C .x m .r. .cos t (a)
(m m )y b .y C .y m .r. .sin t (b)

     


     


(2.5)

o
-
1
-
 
o
(kg); C
x
, C

y
-
theo ph   y (N/m); b
x
, b
y
-      
 - -
-





 
ax
x x cos t  
; y = y
a
sin (t-
y
)
 
2
0
a
2
2 2 2 2
ox x
mr

x
M 4h


    
;
 
2
0
a
2
2 2 2 2
oy y
mr
y
M 4h


    

10

2
0 ox
22
ox
2
ch
a
xx

mr
x
Mh h




;
2
22
2
ch
ox
x
ox x
h





; tg
x


 
22
0
2
x

x
h






ch
x

- Ox


     




lv
=

a


a

ax
/ V
ay

> 1 làm cho ma
 OY 
 lò xo
2.3.1.1 n thit m
o
r
ct

Theo (2.22) rút ra :
 
2
2
2 2 2
ox
0
2
.4
0,46 .
1000.
tt tt
a lv x lv
ct
lv
X M h
m r kg m
  









tt
ox






2
tt
lv
oy
2
kn
M.ω
ΣC
e

(N/m) (2.23)
e
kn

kn

trí m
y


C
oy
=
/
tt
oy y
Cm

= 1478940 /30 = 49298 (N/m).

11

 tính toán 
 theo  

ox
tt
C


lv
2
= 1500. 314
2
=147894000 (N/m)

2.3.2. Xác 
ngang OX
      

a
     
(2.9) :

2
2 2 2 2 2
1000. .
( ) 4 .
o lv
a
ox lv x lv
mr
X
Mh

  


(mm) (2.9)
Thay m
0

ox
= 305,32 (rad/s),
h
x


a
= 0,7944 (mm).

2.3.2.2 
c sau (2.41): V
ax

a
(mm/s)

lv
= 314 (rad/s), X
a
= 0,7944 (mm) vào (2.41) ta có :
V
ax
= 314. 0,7944 = 249,44 (mm/s)
2.3.2.3. B :  


a
X
= 10
-3
X
a

2
(m/s
2
) (2.42)

lv

= 314 (rad/s), X
a
= 0,7944 (mm) vào (2.42) ta có :

a
X
= 10
-3
. 0,7944.314
2
= 78,32 (m/s
2
).




2
2 2 2 2 2
1000. .
( ) 4 .
o lv
a
oy lv y lv
mr
Y
Mh

  




(mm) (2.43)
12

 :
Y
a
= 0,48686 (mm)
2.3.3.2  v

ay

a
(mm/s) (2.55)
T
lv
= 314 (rad/s), Y
a
= 0,48686 (mm) vào (2.55) ta có
V
ay
= 314.0,48686 = 152,87 (mm/s)
2.3.3.3       :    

a
= 10
-3
Y
a


2
(m/s
2
) (2.56)
Thay 
lv
= 314 (rad/s), Y
a
= 0,48686 (mm) vào (2.56) ta có

a
= 0,48686.314
2
.10
-3
= 48 (m/s
2
)


2
Vm
o
r = 0,46 (kg.m); M = 1500 (kg); h
x
=60 (1/s) ; h
y
=50(1/s);
ox

tt
C

=139046752,7(N/m);
oy
tt
C

=1371741 (N/m)

 ( hình 2. 

a

a



a

a

13

2.4.2. 

T  V
ax

ay

 sau:

 th hàm s V
ax

ay


2.4.3. Kho sát hàm gia tc
T  th trên, t biu thc (2.71), (2.72) v  th gia
tc-tn s ( sau:

 th hàm s
a
X

a






14


Hình 2.15  quy trình tính toán có tr giúp ca máy tính
15

Kt lu

    










hk 

        

x
> V
y


, 
 tính 


lv
, 
o

 tính toán 




lv
=314 rad/s
              
22
0,7944 0,4869 0,932A   


lv
=314 rad/s).
16


lv


Y 

3.1. T  
3.1.1. 
3.1.1.1.Các mô h
dùng ph
Mô hình
 

3.1.1.2.Chun s ng dnh chun s ng dng
  
, 
 tính toán thi


  
và 
 i mô hình.  


3   máy  :   máy   
2
3.1.2.1. Ván khuôn thép: 

C
h,
 h.
17


Hình 3.3 Máy rung 2

1. Mt máy     cu
ki       
rung; 4. Cm ng; 5.Cm lò xo
ngang; 6. M   cm lò xo
ngang; 7.Tr ng; 8.  máy; 9. Bu
lông liên k và móng máy.

       
máy rung: 

 c tính


        :
-

 



Các thông s ng lc h c 
phù hp vi yêu cu công ngh, có th c b sung, sa i thit k
 có kt qu ti sn phm. Vi các s liu 
bng 3.2: m
o
r = 0,046 (kg.m); M = 200 (kg); C
t
ox
= 133278 (N/m);
C
t
oy
= 46078,3 (N/m); h
x
= 70 (1/s); h
y
= 60 (1/s) và theo quy trình
tính toán  hình 2.15, ta xây d th sau:

18

a) B - X
a


a



a

a
, m
o
r = 0,046 kg.m
b) - 

 th hàm s V
ax

ay
, m
o
r = 0,046 kg.m
c) Gia - 

 th hàm s
a
X

a
, m
o
r = 0,046 kg.m

3.1.3.5. 
 hành   

o
r khác nhau

19

3 máy rung
mô hình: 
            Xây



- 
o
r .
 -:

a



Hình 3.29  th X
a
- i m
o
r = 0,046 kg.m
ng Y
a

:


a
- 
o
r = 0,046 kg.m

: 
20

t 

- Ma sát  
         
.
- Kt qu y, u chnh ch  
ly các giá tr ln là 0,036 kg.m và 0,046 kg.m  biê t yêu
cu.
3.2. Ch to các mu bê tông tiêu chun bng các máy rung 2
. Máy c dùng 
  u bê tông ht mn bng các khuôn bê tông tiêu chun
(10x10) cm cùng v   Toàn b m c bo
ng 28 ngày theo tiêu chuc th ng
  chng thm trên máy chuyên dùng trong phòng thí
nghim vt liu xây dng ci hc Thy li tuân theo tiêu
chun hin hành.


Hình 3.34. Quan h gi và thi gian R

n
 t

21

a)  

. 

o
r = 0,046 kg.m).


.



Hình 3.36 Quan h gia áp lc thm - thi gian rung - 


, 
m
o

o
r = 0,036

o





 xét chung.
22




  XMLT  





 
 







.

1.  thng hóa ng dng cu máng XMLT trong cc cho
nông nghic thi v ng. Phân loi các
dng mt ct và hình dc kt cu ca cu máng XMLT
ch to bu v chng ca
c    b  chng thm là quan

trng nhi vi kt cu v mng XMLT nói chung và cu máng
23

 có th tính
trc ti           nh qua thc
nghim  chng thm ch thông qua thc nghim.

2. Phân tích ni lc ca c
h ph    u dm và phân tích
theo h không gian dùng phân tích kt cu v mng, áp d
pháp phn t hu hn tính theo chuyn v và ng dng phn mm
 tính toán ng sut và bin dng ca kt cu vi mt thông s
u vào quan tri E bê tông có th i do
các thông s máy rung.

3  ch to kt cu bê tông và
XMLT, làm rõ các tính chn v n ca hn hp bê tông
n tính chm cht, phân tích các nguyên nhân
và bi m lèn ch ng có l
bn và tính chng thm ca bê tông và cu máng XMLT.

4. Nghiên cu t mô hình c to cu
máng XMLT thm c
 m cht hn hp bê tông, luh  xut mt mô
hình máy rung hoàn toàn mo cng
i dng tuyn tính hóa ma sát ca chuyng ca
va bê tông trong mô hình mu qu m cht bê tông,