JimH wrote:
Relatively static? Nope.

Hey, I was/am not nitpicking. Do you see the amount of foot traffic
that bridge handles on both side of the canal?

As I said, if you take static literally, there is NO SUCH THING as a
static load, get it? Let's take a block of concrete sitting on this
bridge. Static? Nope, not if you take it literally. It will gain
moisture (thus mass) when it rains or is humid. It will lose moisture
(thus mass) when it is dry. So, this being cyclic in nature, if you
were to pick nits, it would be dynamic. Is this of VERY little affect?
Depends on the amount of original mass intended for this bridge. Let's
say our block weighs 2 million tons. The amount of dynamic load from
the moisture, drying cycle is almost imperceptable, thus for all
intents and purposes, we assume and design the load as static. Okay,
let's now assume the block weighs a few ounces. Is the moisture now
insignificant? Nope, not by a long shot. THEN we would assume that load
to be dynamic and design the structure for such. Hence: The dynamic
loads applied to that particular bridge by people walking across it are
insignificant because of the massive static load of the water. I'd bet
a lot of money that the only dynamic loads assigned to their analysis
would be wind, earthquake, ponding from rain, snow, and other
significant live loads like if the water rises during rainy seasons,
etc.