Existing Rail Trestle Analysis
Existing Rail Trestle Analysis
(OP)
We are looking at a project that will involve the analysis and rehabilitation of an existing concrete RR trestle. The client is requesting an analysis of the bridge to determine the amount (if any) of strengthening that will be required. The trestle appears to be in decent shape but there is some spalling due to the reinforcement rusting.
My main concern is that there aren’t any existing drawings so determining the size and amount of reinforcing will be tricky. There are a couple of approaches:
1. Assume that the bridge is structurally sound and then go in and rehab the portions of the bridge that need it. Not sure if this would fly with the client.
2. Do invasive testing to determine the size and number of reinforcing. Is there a way to do this without partial demolition?
Just wondering how some of you might approach this. Any and all input welcome and appreciated.
My main concern is that there aren’t any existing drawings so determining the size and amount of reinforcing will be tricky. There are a couple of approaches:
1. Assume that the bridge is structurally sound and then go in and rehab the portions of the bridge that need it. Not sure if this would fly with the client.
2. Do invasive testing to determine the size and number of reinforcing. Is there a way to do this without partial demolition?
Just wondering how some of you might approach this. Any and all input welcome and appreciated.






RE: Existing Rail Trestle Analysis
If you place limitations on the inspection, then state so in the report, subject to the needs of the client.
Thedre are methods to determine the location and size of the rebar, within certain constraints. There are various forms of non-destructuve testing equipment out there in the market you can check out on the web. One may give you what you need. There are also special testing agencies you can hire. Personally, I would not do destructuve testing unless absolutely necessary, especially if this bridge is currently seeing trraffic.
Mike McCann
MMC Engineering
http://mmcengineering.tripod.com
RE: Existing Rail Trestle Analysis
There's almost no way to scope this high enough.
RE: Existing Rail Trestle Analysis
Michael.
Timing has a lot to do with the outcome of a rain dance.
RE: Existing Rail Trestle Analysis
I've done a few proposals for these lately, and my proposals are always very clear as to what I will be able to provide and what limitations there will be. My company doesn't do any NDE, but I think there are products out there that will allow you to locate reinforcing and give approximate size. I will say that I have seen reports from a company on another project I did, and I wasn't impressed with the ability to determine reinforcing specifics. I was given "ranges" of locations and approximate sizes of rebar. Then you don't know grade of steel or strength of concrete...still unknowns.
RE: Existing Rail Trestle Analysis
Thanks again,
PBW2