e-mosty June 2017: Osman Gazi B. US Suspension. Hålogaland B. e-mosty June 2017: Suspension Bridges | Page 57

Figure 16: Air trials with soapy water test on in-situ cable band
(note bubbles detecting leaks around
cable band bolts and suspender ropes)
Following the initial tests, suspender ropes were
caulked within the cable band guides, and the cable
band bolts were cleaned and coated with an
elastomeric acrylic coating system for a subsequent
air trail. These details were proven to be sufficiently
airtight for the purposes of dehumidification and were
therefore implemented on the remaining cable bands
(Figure 17).
Figure 18: Shop test rig
The test rig was required to be constructed to allow
pressure testing and detection of leaks along the wrap
and interface with the cable bands through soapy water
inspection (Figure 19).
Figure 19. Soapy water inspection of cable wrap on shop test rig
(note the bubbles indicating
air leaks in the overlap areas)
Figure 17: Eastbound cable band with new elastomeric acrylic
coating system
The successful completion of the main cable wrapping
and sealing began with contractually required shop
trials. The contractor was required to demonstrate
the ability to provide an airtight wrap, including the
cable band seals, prior to applying the wrap and cable
band sealing details on the bridge (Figure 18).
Once the contractor successfully demonstrated the
ability to wrap and seal the cable bands on the test
rig, contractual provisions required two experimental
panels on each bridge to be wrapped and heat sealed
to the satisfaction of the construction management
team. The purpose of the experimental panels was to
demonstrate that the contractor could replicate the
performance witnessed on the test rig while adapting
to the actual cable and field conditions. This was
particularly important for the heat sealing of the
wrap, as field conditions such as ambient temperature
affected the heating cycles required for proper sealing
of the wrap.
2/2017