Prutkova Eugenia and Ryabchenkov Sergei

1
JASS-2006

• Prutkova Eugenia and Ryabchenkov Sergei

Represent
Report on the theme
2
The wind loadsin building
JASS-2006
Presented on JASS 2006, Saint-Petersburg
3
Part I Wind loads
JASS-2006
Content
Part II Effects from wind loads
Part III Influence of wind loads on the
exploitation of the building
by Prutkova Eugenia and Ryabchenkov Sergei
4
Wind loads
JASS-2006
Part I
by Prutkova Eugenia and Ryabchenkov Sergei
5
The normative valueof wind pressure
JASS-2006
Part I Wind loads
by Prutkova Eugenia and Ryabchenkov Sergei
6
JASS-2006
Figure 1 Map of wind zoning
Part I Wind loads
7
JASS-2006
Part I Wind loads
Figure 2 Map of wind zoning (part)
8
JASS-2006
Part I Wind loads
Table 1 Calculated values of wind pressure on
the height of buildings
Height, meters Coefficient K for citys
5 0.4
10 0.4
20 0.55
40 0.8
60 0.8
80 1.0
100 1.15
by Prutkova Eugenia and Ryabchenkov Sergei
9
JASS-2006
Part I Wind loads
Figure 3 The scheme is used for collection loads
of building
the coefficient of dependability is
by Prutkova Eugenia and Ryabchenkov Sergei
10
JASS-2006
Part I Wind loads
(2)
- the normative value of wind pressure at
the level of 10 metres over the surface of the
ground, which corresponds 10-min. interval of
averaging.
Table 2 Dependence coefficients K1 and K2 from
averaging interval
The averaging interval 10 min 2 min 1 min 10 sec 3 sec
The correction coefficient on the average speed K1 1,00 1,10 1,15 1,29 1,41
The correction coefficient on the average wind pressure ?2 1,00 1,21 1,32 1,66 1,99
by Prutkova Eugenia and Ryabchenkov Sergei
11
JASS-2006
Part I Wind loads
(3)
?1?- value of cofficient ?1 on height ? under
ground level
by Prutkova Eugenia and Ryabchenkov Sergei
12
The determination of the resulted wind loads,
acting on buildings and structures
JASS-2006
Part I Wind loads
by Prutkova Eugenia and Ryabchenkov Sergei
13
JASS-2006
Part I Wind loads
Figure 4 The design scheme for tall buildings
Wind
(4)
forces from action of the wind, according to the
axes X,Y,Z
moments, caused action of the wind, about this
axes
by Prutkova Eugenia and Ryabchenkov Sergei
14
JASS-2006
Part I Wind loads
Figure 5 Level of pressure by streamlines of air
flow
relative dimensionless value of the pression
by Prutkova Eugenia and Ryabchenkov Sergei
15
Some words about aerodynamic tube
JASS-2006
Part I Wind loads
Figure 6 The principal scheme of aerodynamic tube
by Prutkova Eugenia and Ryabchenkov Sergei
16
The determination of distributed wind loads,
acting on surface of the building
JASS-2006
Part I Wind loads
by Prutkova Eugenia and Ryabchenkov Sergei
17
JASS-2006
Part I Wind loads
(5)
S the square of the element
(6)
??1 - the absolute peak (maximum) meaning of the
coefficient rarefaction on the surface of the
building
by Prutkova Eugenia and Ryabchenkov Sergei
18
Effects from wind loads
JASS-2006
Part II
by Prutkova Eugenia and Ryabchenkov Sergei
19
Resonance cases
JASS-2006
Part II Effects from wind loads
(7)

• N - the frequency of break-down vortex, in Hertz
  
• D - the specific size of object
• V - the speed of incoming air flow
• Sh - is determinated of the shape by traversal
  sectional view of streamlined building, the angle
  of incoming air flow a

by Prutkova Eugenia and Ryabchenkov Sergei
20
Galloping
JASS-2006
Part II Effects from wind loads
Figure 7 The principal scheme of Galloping
case
by Prutkova Eugenia and Ryabchenkov Sergei
21
JASS-2006
Part II Effects from wind loads
(8)

• - selfrelative constructional damping action
  
• - frequency of the self oscillations of the
  building
• - the density of the air
• V - the velocity of the incoming flow
• ? - the specific size of traversal sectional view
  of the building
• - the speed movement of the element of the
  building in the direction, perpendicularly to
  the speed V
• - coefficients of the elevating forces and
  resistance of the element of the building in
  axes, connected with the resulted speed vector
  of air flow (figure 8).

by Prutkova Eugenia and Ryabchenkov Sergei
22
JASS-2006
Figure 8 Cross-section of elastic-fixed body
Part II Effects from wind loads
vx
x
x
v
v
y
y
The connection CL and CD with final speed vector
of the air flow
(9)
measure Glauert-Den Gartog
(10)
by Prutkova Eugenia and Ryabchenkov Sergei
23
JASS-2006
Part II Effects from wind loads
(11)
From this two formulas the extreme meaning of
the speed V could be found, which starts the
condition of galloping
(12)
by Prutkova Eugenia and Ryabchenkov Sergei
24
Divergency
JASS-2006
Part II Effects from wind loads
Figure 9 Collapse of Tacoma bridge
by Prutkova Eugenia and Ryabchenkov Sergei
25
JASS-2006
Part II Effects from wind loads
(13)

• the normative value of the speed pressure at the
  height of building H,
• the angle of coming to the building air flow,
• the change of the angle due to the
  intertwisting of the building,
• the stiffness coefficient of the building in the
  case of twisting

(14)
by Prutkova Eugenia and Ryabchenkov Sergei
26
JASS-2006
Part II Effects from wind loads
otherwise
(15)
according to this the change of the angle can
be found
(16)
by Prutkova Eugenia and Ryabchenkov Sergei
27
Influence of wind loads on the exploitation of
the building
JASS-2006
Part III
by Prutkova Eugenia and Ryabchenkov Sergei
28
JASS-2006
Part III Influence of wind loads onthe
exploitation of the building
Figure 10 The scheme of tall building
by Prutkova Eugenia and Ryabchenkov Sergei
29
JASS-2006
Part III Influence of wind loads onthe
exploitation of the building
Table 3 Dependence the level of discomfort
from the value of acceleration
The level of discomfort. oscillations acceleration (in percent from acceleration gravity force)
insensible 0,5
appreciable 0,5 1,5
stimulated 1,5 5
extremely stimulated 5 15
intolerable gt15
by Prutkova Eugenia and Ryabchenkov Sergei