Public Information Transcripts - Whittier Bridge/I-95 Improvement ...

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blew it up and dropped it into the lake.
As you can see, they were evaluating
different bridge types. And they’ve come up with
this, which is known as the modified network arch. It
has some similar lines to that structure, and it was
deemed to be the preferred option. This is kind of a
close-up of its rendered view. It has this unique
feature of almost like a fulcrum arm. And that’s
basically what it is in terms of a lever arm. And it
works well for this location. The span lengths are
very long. This is what we call the back span, or the
approach span, to the bridge is very long so that when
you look at my example here, basically a lever arm
example, there’s this portion of the bridge from here
to here that gets supported on this fulcrum. That
weight needs to be counteracted by the weight of the
structure to hold it back. And this structure is very
graceful and works well. Unfortunately for us, our
pier and abutment location, we have a relatively short
back span. The math doesn’t work. It’s not an
economical bridge.
Our bridge, as supported, with the
intention we’d have to fold it down. That’s not a
desirable bridge design element. So, actually, we’ve
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