| 1. |
Corrosion can threaten the long-term function and integrity of a steel bridge. Structural steel will corrode if left unprotected or inadequately protected from the natural environment. It is a ___________ that generally takes several years to develop deterioration significant enough to cause concern. |
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time based process |
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not a time based process |
| 2. |
Which one below shows performance of corrosion protection systems on a bridge |
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The quality of application of protective coating systems, including particularly, the quality of surface preparation prior to coating application, |
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Expected damage or deterioration the coating expects to receive during service, |
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The severity of the general exposure of the macro-environment, and |
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The severity of localized micro-environments within the bridge that is a function of bridge detailing discussed later in the volume. |
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All of the above |
| 3. |
Which one of the following corrosion mitigation strategies have risen in popularity for use with steel bridges |
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corrosion-resistant steel |
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zinc-rich primer paint systems |
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hot-dip galvanizing |
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thermal spray metalizing |
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All of the above |
| 4. |
For several decades, the predominant protective coating system used for bridge steel was several coats of lead-containing alkyd paint. This system was inexpensive, easy to apply, and provided reasonable corrosion protection as long as periodic maintenance painting was performed. |
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True |
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False |
| 5. |
The majority of state highway departments currently specify the use of some type of zinc-rich primer based coating system and this has now been the case for many years. Zinc-rich coatings are typically either two or three coats of paint with the primer coat having a heavy loading of zinc pigment to provide cathodic protection. |
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True |
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False |
| 6. |
Figure 3 shows: |
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The aerial view of a parking structure with metal roofings |
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Testing of various generically similar paint systems shows wide variations in performance. |
| 7. |
Metalizing is a term used to describe the process of thermal spraying a metal coating onto a substrate like steel. The thermal spray industry is mature and can be highly technical for some applications. However, metalizing as presently applied to the corrosion protection of bridge steel is straightforward. |
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True |
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False |
| 8. |
Figure 6 illustrates |
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Staples used for a staple gun |
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Stages of the hot-dip galvanizing process |
| 9. |
Figure 15 is an example of Deterioration of bearing area beneath a leaking joint with only single-coat inorganic zinc-rich paint. |
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True |
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False |
| 10. |
Figure 16 shows |
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The corroded panels inside an industrial HVAC chilling unit. |
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Steel directly beneath transverse expansion joints that have leaked corrosive runoff from the deck. |
| 11. |
Certain areas of the steel structure below the roadway surface will see the majority of drainage and runoff from the deck above. These areas will have a higher time of wetness than the rest of the steel structure. They will also receive an increased level of dirt and debris from the roadway. This is critical in areas that receive significant amounts of deicing salt. These areas will often have ________ corrosion rate relative to the rest of the bridge. |
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A much higher |
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A much lower |
| 12. |
Figure 22 is an example of : |
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Crude oil spillage from a refinery cooling tower |
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Clogged drain leaking water onto superstructure |
| 13. |
Figure 26 shows: Accelerated corrosion on the inbound fascia girder of a grade separate structure, particularly over the right travel lane. |
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True |
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False |
| 14. |
In Figure 27 and figure 28 The lower portions of flanged structures corrode early due to ___________ of wetness for these parts relative to the rest of the bridge, because they are likely horizontal and can pond water. The higher time of wetness is also caused by preferential condensation on the lower portions of a steel element. While not a recommendation of this handbook, an ideal solution would be to curve the lower flange such that water could not pond on it. |
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Lower time |
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Higher time |
| 15. |
The inherent corrosivity of many natural environments and the highly corrosive nature of deicing salts applied to highways over much of the U.S. create challenging conditions for the long-term maintenance-free function of a bridge. Corrosion can be a considerable risk to a steel bridge, however, designers have many corrosion protection options at their disposal to mitigate that risk. |
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True |
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False |
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