INSPECTION REPORT ON ROOF TRUSSES
Sample Report
West Orange, NJ
February 20, 2003
On Thursday, February 20, 2003 Dajon Associates inspected
the 65' span bowstring roof trusses at the above referenced
site. The inspection followed the heavy snows that fell on
or around February 17, 2003 and caused on roof truss to fail.
For the purpose of this report the trusses are numbered T1
through T3 with T1 located nearest the front of the building
at Columbia Street. (Called East) The individual truss members
are numbered from the south side of the building to the north
end. The area of the truss construction is utilized as a warehouse.
The trusses are constructed with heavy timber chord members,
side by side. The species is presumed to be Douglas Fir. The
web members are 4" x 4" common lumber. Mechanical
fasteners are ¾" through bolts at all web to chord
members and 1" through bolts at splice plates and heel
connections. The steel heel connection wraps around the back
end of the bottom and top chords and forms a kick plate effectively
tying in the 2" x 3" mechanically laminated top
chords forming the bearing points of the truss.
Findings:
Truss #1: Bottom chord #1 east is badly split at the
2nd panel point this split appears to be recent in nature.
A large knot in the immediate proximity of the connection
is fracturing downward through the bottom face of the chord.
This truss member requires remedial work.
Truss #1 Bottom chord #1 East
Truss #1 Bottom chord #1 East
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Truss #2: Bottom chords #1 east and west are fractured.
The web members in this immediate area as well as filler block
have also fractured or split. Bottom chords #2 east and west
have split at 5th panel point. These 4 (four) chord members
require remedial work. The truss has experienced a "tension
failure" and as a result the bottom chords fractured
and pulled apart. This ultimately caused the truss drop significantly.
The radius formed by the top chord has flattened out. The
associated web members and splice plates will also require
remedial work. The truss must be shored and properly jacked
back to original elevation and configuration or as close as
possible.
Truss #2 Bottom chord #1 East
Truss #2 Bottom chord #1 West
Truss #2 Bottom chord #2 West
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Truss #3: The truss experienced a lateral force from
adjoining bracing connected to the failed Truss #2. No truss
members have fractured however there is some splitting seen
in the bottom chords. All other truss members appear to be
in good condition.
Truss #3 Bottom chord #1 East
Truss #3 Bottom chord #1 West
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Truss Configuration
Span: 65'
Profile 9'3"
On Center: 20'
Bottom chords: 2 ½" x 9 ½" x
32'
Top chords: 6 laminations @ 2" x 3" Mech.
Laminated to form radius.
Web members; 4" x 4"
W1& 22: 3' Vertical
W2& 21: 6'
W3& 20: 6'
W4& 19: 6'3"
W5& 18: 8'
W6& 17: 8'
W7& 16: 8'2"
W8& 15: 9'6"
W9& 14: 9'7"
W10&13:9'10"
W11&12:9'10"
No Scale/Half Span
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