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286 L’ARC, LE CÂBLE ET LA STRUCTURE HAUBANÉE

– l’ajout d’une rotule à la clef lorsque l’arc est bi-encastré alourdit la structure de l’ordre de 10% dans les mêmes
cas usuels (figures 5.4.4.1. à 5.4.4.3.) ;
– finalement l’arc à trois rotules est encore de l’ordre de 30% plus lourd que celui à une rotule (figures 5.4.6.1. à
5.4.6.3.) ou, en vertu de ce qui précède, 33% plus lourd que l’arc bi-encastré.

a x a x
F x' F x'

N yN T N yN T
AT H AT H

h h

B B

Rh,A Rh,B Rh, A Rh,B

Figure 5.4.1.1. Rv, A Rv,B Figure 5.4.2.1. Rv, A Rv,B

L L

0.5 0.4 0.3 0.2 0.1 0 0.1 0.2 0.3 0.4 0.5 0.5 0.4 0.3 0.2 0.1 0 0.1 0.2 0.3 0.4 0.5
0
0 a/L = –0.4
a/L = 0.4

a/L = 0.4 a/L = –0.4

-0.2 -0.2 a/L = –0.3
a/L = 0.3

-0.4

a/L = 0.3 a/L = –0.3
-0.4
-0.6 a/L = 0.2 a/L = –0.2
-0.8
-0.6
a/L = 0.2 a/L = –0.2

-0.8 -1 a/L = 0.1 a/L = –0.1

-1.2

-1 a/L = 0.1 a/L = –0.1

-1.4

Figure 5.4.1.2. -1.2 a/L = 0 Figure 5.4.2.2. -1.6 a/L = 0 a/L = –0.4
Figure 5.4.1.3. L =5 Figure 5.4.2.3. L =5
Figure 5.4.1.4. N/ F H Figure 5.4.2.4. N/ F H
Figure 5.4.1.5. -1.4 Figure 5.4.2.5. -1.8
Figure 5.4.1.6. L =5 Figure 5.4.2.6. L =5
1 H 1 H
T/F T/F

0.8 a/L = 0.4 0.8 a/L = 0.4

a/L = –0.4 a/L = 0.3 a/L = –0.3

a/L = 0.3 a/L = –0.3 0.6 a/L = 0.2 a/L = 0.1 a/L = 0 a/L = –0.1 a/L = –0.2
0.6
a/L = 0

a/L = 0.2 a/L = 0.1 a/L = –0.1 a/L = –0.2 0.4

0.4

0.2

0.2 0

0 -0.2

-0.2 -0.4

-0.4 -0.6

-0.6 -0.8 a = 0.3 a = 0.2 a = –0.2 a = –0.3
0.0 8 0.0 8 L L L L

M/(FL) a = 0.3 a = 0.2 a = –0.2 a = –0.3 M/(FL)
L L L L
0.0 6 a = 0.1 a =0 a = –0.1 0.0 6 a = 0.1 a = –0.1
L L L L L

0.0 4 a = 0.4 a = –0.4 0.0 4 a = 0.4 a = –0.4
L L 0.0 2 L L

0.0 2

0 0

-0.0 2 -0.0 2
-0.0 4
a =0
L

-0.0 4

-0.0 6 -0.0 6 L =5
H
-0.0 8 Nmax/F L =5 -0.0 8 Nmax/F
5 H 7 L = 20
H
4.5 L = 20 6
H
4
15
5
10
3.5 8
6
3 4 4
2
2.5 1 3 15
0.5
2 2 10
L = 0.5
1.5 H 1 8
6
1 1 0 4
2 1 .2 2
0.5 4 1
20 Tmax/F 0.5

0 0.078 1 20 0.078
1 .2 15
Mmax/(FL) 10 20 Mmax/(FL)
Tmax/F 8
0.065 L = 0.5 0.065
20 0.8 6 H 0.052
1 15 0.052 4
0.039
10 0.039 0 .6
8
0.8 6 0.026 2
0 .4
4
1
0 .6 0 .2

2 L = 0.5 0.026
0 .4 H
0
1 0.013 0.013
0 .2 0
0
L = 0.5
H

0