Quantcast Evidence of Decay - mo111_10037

Share on Google+Share on FacebookShare on LinkedInShare on TwitterShare on DiggShare on Stumble Upon
Custom Search
 
  
 


For tension members with connectors (bolts or split rings) loaded parallel
to the grain. a single split within the connector area may be disregarded if the
opening is less than 3/16 inch for connectors of 2-5/8 inches or less in diameter.
and less than 1/4 inch for connectors up to 4 inches in diameter. All measurements
of opening of splits should be made at the end of the member. If there is more
than one split in the connector area. the total opening of the splits should not
exceed 1-1/2 times that for one split. Splits of any width should be considered
significant if they are within 1/4 inch of the edge of a connector that is 2-518
inches or less in diameter or within 1/2 inch of the edge of a connector that is
up to 4 inches in diameter.
For end splits in either tension or compression members with connector loads
acting in a direction other than parallel to the grain. the suggestion above for
treating tension members should be applied at the ends of the pieces.
In some cases splits completely divide a column into two parts resulting in
the parts acting as two smaller columns This condition necessitates an engineering
analysis to determine if the column is structurally adequate. This situation should
receive a 40 rating (Fig. 3-5E). These splits should also be checked to see if
they are trapping water or providing a termite pathway.
3.1.3 LOOSE CONNECTORS.  Connectors that appear loose either by
sighting a gap between members or by sounding should be noted as loose and
requiring attention. Inspections made during the first 3 years should include check-
ing each bolt with a torque wrench. This should accomodate any initial drying
of the member. Older trusses should be checked with a torque wrench if there
are signs of excessive sag or indications of rain leakage in the vicinity of con-
nector. Visual observation may be adequate for older trusses that have remained
stable for several years.
3.1.4 EVIDENCE OF DECAY.  Dry wood will not decay. Moisture con-
tent of wood is one of the most significant factors regarding wood decay because
considerable water is necessary for fungus growth. Thus during inspection of
roof trusses for decay, it is important to survey the area for any source of moisture
that will sufficiently wet wood. Column bases are particularly vulnerable when
they are supported directly on concrete because they may pick water up from
the concrete (Fig. 34C). Water necessary for decay development in roof trusses
can come from several sources: (1) rainwater leaks through the roof, (2)
snowmelt, (3) condensation and (4) piped water in a leaking line.
3.1.4-A RAIN WETTING.  Most rainwater wetting of roof trusses will
be by gravity flow through leaks in roofs. With a good light source, survey the
roof area for evidence of discoloration in wood caused by water leaks. Water
3-3





 


Privacy Statement - Copyright Information. - Contact Us

Integrated Publishing, Inc.