I have a project where I need to find out what materials are used to make Maryland bridges corrosion proof. Please have a link for me, I need it for resources.
There are two basic forms of rust protection for metal structures.
One is paint, or “coatings” as it is technically called. Most coatings consist of a primer coat which is applied to a clean surface followed by one or more coats of paint.
There are many different kinds of coatings and final selection depends on the specific requirements for a project such as magnitude of exposure to moisture, salt and other chemicals. It also depends on the cost effectiveness the owner requires. Do you want an expensive paint that lasts 25 years? Or is it cheaper to just to re-paint every five years? Economics does play a large role.
The other method used to protect steel is called “Galvanizing”, where the steel is dunked in a bath of molten zinc and an electrical process is used to bond a lauer of zinc to the steel.
Again, choosing between galvanizing or coating depends largely on economics and the desired life-span and serviciability of the structure.
As for Cor-Ten Steel: This is a special steel alloy that rusts in the surface and the rust itself becomes the proctecting layer for the steel underneath. Because of its higher price, and different mechanical properties from ASTM A36 or A572 steel, it is not used often.
Always remember, economics are always a big factor in any big project. Sometimes concrete is more available so bridges may be built of concrete as well.
Hope this helps.
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I don’t have a link but look up Cor 10 steel.
Pronounced "core ten"
References :
There are two basic forms of rust protection for metal structures.
One is paint, or "coatings" as it is technically called. Most coatings consist of a primer coat which is applied to a clean surface followed by one or more coats of paint.
There are many different kinds of coatings and final selection depends on the specific requirements for a project such as magnitude of exposure to moisture, salt and other chemicals. It also depends on the cost effectiveness the owner requires. Do you want an expensive paint that lasts 25 years? Or is it cheaper to just to re-paint every five years? Economics does play a large role.
The other method used to protect steel is called "Galvanizing", where the steel is dunked in a bath of molten zinc and an electrical process is used to bond a lauer of zinc to the steel.
Again, choosing between galvanizing or coating depends largely on economics and the desired life-span and serviciability of the structure.
As for Cor-Ten Steel: This is a special steel alloy that rusts in the surface and the rust itself becomes the proctecting layer for the steel underneath. Because of its higher price, and different mechanical properties from ASTM A36 or A572 steel, it is not used often.
Always remember, economics are always a big factor in any big project. Sometimes concrete is more available so bridges may be built of concrete as well.
Hope this helps.
References :