Bridge "Rehab" vs. "Retrofit" 1

[BlastResistant]

Hi everyone,

Can someone please tell me what the official difference is between a "rehabilitation" versus a "retrofit"? I searched the web for a while and couldn't find anything definitive. Is there also an legal AASHTO or FHWA definition?

Thanks in advance.

 

[Qshake]

BlastResistant -

I don't believe there is a hard and fast definition but will offer my experienes as I have been routinely involved in both for many years. Even the definitions below probably aren't etched in stone.

Rehabilitation includes work to restore the original capacity to meet typical service loads and conditions experienced by the structure. For example, patching a bridge deck, or replacing spalled concrete are part of rehabilitation.

Retrofit involves strengthening the structure to meet loads or conditions it was not originally designed to experience. Examples include extreme events such as blast and earthquake. Others may include strengthening to resist heavier live loads.

I hope that helps.

Regards,
Qshake

Eng-Tips Forums:Real Solutions for Real Problems Really Quick.

 

[bridgebuster]

Some agencies use "renovation" & "reconstruction" in lieu of "rehabilitation."

As Qshake said there are no hard & fast rules. It's like that old song goes: "...you say toe-may-toe", I say toe-maah-toe..."

From experience, rehabilitation is the more common term and it means some type of major work.

 

[TTK]

Although definitions can vary from region to region, Qshake provided what I would consider to be the best definition of these terms.

 

[Drumchaser]

my 2 cents

rehab - invasive operation(s) that are costly and will add extended life to the structure and or riding surface.

retrofit - to me this would apply to something such as: T-501 bridge rail retrofit. Pertaining to upgrading the existing rail (old) to current standards (T-501), which will include the latest transitions to the MBGF etc. and so on.
(removing the old rail, doweling in and replacing with a better/safer product) "T-5 retrofit"

hope this helps

 

[LobstaEata]

Dictionary definitions as follows may provide the insight you are seeking.

Retrofit = To provide (a bridge) with parts, devices, or equipment not in existence or available at the time of original construction.

Rehabilitation = To restore to good condition, operation, or capacity.

Hope this is helpful.

 

[facca]

The last are excellent from a contractors point of view.

 

[MichSt]

The essence of each term is covered well by everyone here. However, as others have said, different terms are used by different agencies, and are usually connected to a very specific set of requirements for design. For example, in Michigan the DOT uses “rehabilitation”, “reconstruction”, and “replacement”. All of these terms mean something very specific and have a set of design criteria associated with them. If you are doing work for a public agency you may want to consult you state’s bridge design manual or talk to the bridge owner.