Civil Engineering Reference
In-Depth Information
Work on site
Inspection
It is important to establish if a partition has
any structural role, using drawings if
available, or by site checking of joist spans
and other adjacent structural elements.
Crack patterns should be examined for
indications of the cause of movement. It is
often useful on site to record height and
thickness of masonry partitions and timber
sizes and spans of stud partition for later
'desk checking'. Plumbness and any
evidence of bowing should be noted.
A partition should be examined to
determine whether it is protecting an escape
route. Fire resistance of the partition wall
construction should be assessed and, where
cavities exist, an optical probe examination
might be considered desirable.
Likely sound reduction values should be
estimated and compared with criteria. Holes,
gaps, glazing and imperfections should be
noted, together with voids that could
conduct sound through or around a partition
(Figure 7.8).
The problems to look for are:
Figure 7.7
Here the short return is inadequately
bonded to carry the two lintel bearings,
resulting in likely poor load carrying
capacity for the massive floor trimmer over
Figure 7.8
A hot air heating duct through a partition.
There is no lintel and the infilling block has
already dropped
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instability (no returns, pinning to ceiling,
or support from full height framing)
In the case of loadbearing walls,
one of the most likely causes of
cracking is poor bonding of masonry.
On many occasions, BRE
investigators on site have seen very
poor bricklaying practices (Figure
7.7). Also there is the risk of cracking
through shrinkage, as in the non
loadbearing case described above.
no lintels (walls carried on door frames)
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removal of existing supports to roofs or
floors during rehab
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unintended loadings from roofs or floors
inadequate fire resistance
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cracking (shrinkage of materials or of
supporting suspended floors)
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asymmetrical loadings (eg from water
storage tanks)
