Civil Engineering Reference
In-Depth Information
Table 7.3
Classification of building damage (from Devriendt 2006, after Burland
et al.
1977 and Boscardin and Cording 1989)
Damage
Description of typical damage
Approx.
Limiting
category
(ease of repair in italics)
a
crack
tensile
width
strain
(mm)
b
(%)
0 Negligible
Hairline cracks of less than about
0.1 mm
0-0.05
0.1 mm are classed as negligible
1 Very slight
Fine cracks which can easily be treated
1 mm
0.05-
during normal decoration.
Perhaps
0.0075
isolated slight fracture in building.
Cracks in external brickwork visible
on inspection.
2 Slight
Cracks easily filled. Redecoration
5 mm
0.075-
probably required.
Several slight fractures
0.15
showing inside of the building. Cracks are
visible externally and some re-pointing
may be required externally to ensure
weather tightness. Doors and windows
may stick slightly.
3 Moderate
The cracks require some opening up and
5 to 15 mm, 0.15-0.3
can be patched by a mason. Recurrent
or a number
cracks can be masked by suitable linings.
of cracks
Re-pointing of external brickwork and
3 mm
possibly a small amount of brickwork to
be replaced.
Doors and windows sticking.
Service pipes may fracture. Weather
tightness often impaired.
4 Severe
Extensive repair work involving
15-25 mm
0.3
breaking-out and replacing sections of
walls, especially over doors and windows.
Windows and door frames distorted,
floors sloping noticeably. Walls leaning or
bulging noticeably, some loss of bearing
on beams. Service pipes disrupted.
5 Very severe
This requires a major repair job involving
usually
0.3
partial or complete rebuilding.
Beams lose
25 mm,
bearings, walls lean badly and require but
shoring. Windows broken with distortion. depends on
Danger of instability.
number of
cracks
Notes:
(a) In assessing the degree of damage account must be taken of its location in the building
or structure.
(b) Crack width is only one aspect of damage and should not be used on its own as a direct
measure.
