Abqfoamer Wrote:
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> Still makes no sense to me.
>
> Their scope of investigation seems too limited,
> given the discovered span warping, lifting of
> abutment anchors, concerns that the original
> safety factor may now be less due to heavier locos
> using Lobato. Why not investigate ALL essential
> factors involved in rebuilding the structure?
Paul, I agree with what you're saying, but the approach documented in the report does make a lot of sense to me. Consider three points:
(1) In order to investigate
"ALL essential factors involved in rebuilding the structure", you need different types of expertise. To investigate the superstructure, you need engineers and technicians who are capable of safely climbing the bridge and can do their work while suspended from the bridge. To investigate the substructure, you need engineers and technicians who are qualified at subsurface investigations...which is a very different expertise.
(2) If it were my project (thankfully it's not!), I would start at the top and work my way down. I would figure out what is needed to be done to the spans and, once I knew that, I could calculate how much extra loading (weight) that added to the substructure. For example, if the evaluation determined that it was necessary to add extra beams between the existing beams, those new beams would add extra loading.)
I would only start the analysis of the substructure once I knew how much loading the repaired or replaced superstructure would be applying to the substructure.
(3) We don't know how much money was available to fund the investigation. IMHO, limited funds were best spent on investigating the spans.
Other NGDF posters have suggested that us Lobato posters should shut-up and be quiet until the next C&TS Commission meeting. IMHO, unless the commission has already contracted an analysis of the substructure, there will be no "Plan for repair of Lobato Trestle" by the September 30, 2010 Commission meeting... which is only 3 weeks and 3 days from now.
--
Chris Webster
