Civil Engineering Reference
In-Depth Information
Continued
Deformation
Types of steel structures or members
a
b
c
d
Girders
L/
400
>
level “
a
”
>
level “
a
”
>
level “
a
”
deformation,
deformation,
deformation,
Solid beams
Other beams
L
/250
having no
having partial
having
functional
functional
functional
influence
influence
influence
Light and medium duty
>
level “
a
”
>
level “
a
”
L/
600
(
Q<
50
t
) bridge cranes
>
level“
a
”
deformation,
deformation,
deformation,
having partial
having
having no
functional
functional
Crane beams
Heavy and medium
L/
750
functional
influence on
influence on
(
Q>
50
t
) bridge duty
influence on
service of
service of
service of crane
crane, can be
crane, cannot
remedied
be remedied
Transverse deformation
>
level “
a
”
>
level “
a
”
H
T
/
1250
of factory columns
>
level“
a
”
deformation,
deformation,
Transverse deformation
deformation,
having partial
having
Columns
of outdoor trestle
H
T
/
2500
having no
functional
functional
columns
functional
influence on
influence on
Longitudinal
influence on
service of
service of
deformation of factory
H
T
/
4000
service of crane
crane
crane, cannot
and trestle columns
be remedied
Cross beams sustaining
L/
300
masonry (horizontal)
>
level“
a
”
>
level“
a
”
>
level“
a
”
Wall-frame
Light wall cross beam
deformation,
deformation,
deformation,
members
(horizontal) as profiled
L/
200
having no
having
having severe
steel sheets,
functional
functional
functional
corrugated iron
impact
impact
impact
Post shorings
L/
400
Notes: 1) “
L
” in this table is the span of bending member. “
H
T
” is the height from bottom surface of
column to top surface of crane beam or crane truss. Deformation of column is the horizontal deformation
resulting from horizontal load of the heaviest crane.
2) The deformation values listed in this table result from the long-time load effect combination, which
need minus or plus value of fabricating invert arch or down deflection.
Table 2.14
Assessment of crack width of masonry structures or members
No.
Structures or
Deformation crack
a
b
c
d
members
With slight cracks
With considerable
With severe cracks
1
Walls and
No crack
on wall,
cracks on
on the wall,
pilastered walls
widest crack
wall, widest
the widest crack
width
<
1.5 mm
crack width between
width
>
10 mm
1.5 mm and 10 mm
Widest crack
With column
2
Independent
width
1.5 mm,
fracture or
columns
No crack
No crack
and not through
horizontal
column cross section
displacement
Note: This table is only applicable to masonry structures made of clay bricks, silica bricks, and fly ash
bricks.
