TM 5-5420-280-23&P
0030 00
BRIDGE AND PALLET CRACK DEFORMATION INSPECTION AND REPAIR (Contd)
NOTE
GDSBS recommend after any welding, post heat treatment. If there
is no possibility to perform a post-heat treatment, natural aging of
30 days at 68 F (20 C) is also permitted. Natural aging may cause
a high risk of stress corrosion cracking.
j.
If heat treated, welding repair must be heated for 24 hours at a temperature of 257 41 F
(1255 C). Welded component must be subjected to heat treatment for the following reasons:
(1) To relieve inherent stresses.
(2) To restore original strength.
(3) To restore resistance to exfoliation corrosion and stress corrosion cracking.
Table 2. Critical Crack Length.
SENTENCING
CRACK LOCATION
TYPE OF INSPECTION
UNDER OBSERVATION
UNSERVICEABLE
Bridge top deck, underside and
1.181 in.
3.150 in.
Visual
ramp end (roadway)
(30 mm)
(80 mm)
Girder top &
0.787 in.
2.362 in.
Visual
Bottom middle and ramp
(20 mm)
(60 mm)
Square tubes
0.984 in.
2.362 in.
Visual
Front & crossgirders
(25 mm)
(60 mm)
Side outer plates
1.181 in.
4.724 in.
Visual
Side outer middle and ramp plates
(30 mm)
(120 mm)
Coupling receptacle
Visual or with x 10
0.236 in.
0.472 in.
and connector
magnifying aid
(6 mm)
(12 mm)
Support rail areas and side plates
0.394 in.
1.181 in.
Visual
at coupling area
(10 mm)
(30 mm)
Table 3. Critical Crack Length.
(measurement on width or height of part)
SENTENCING
LOCATION
UNDER OBSERVATION
UNSERVICEABLE
Roadway
0.591 in. (15 mm)
0.984 in. (25 mm)
Bottom Girder
0.276 in. (7 mm)
0.472 in. (12 mm)
Side sheet
0.315 in. (8 mm)
0.591 in. (15 mm)
.
0030 00-4
