--- In BRHSlist@y..., Bill Chambers <ace1942us@y...> wrote:
" When the CZ crossed the river, I noticed that the old
> bridge had been removed and a 2-truss installed. Do
> you have any idea when this happened, and why the old
> bridge was replaced?
Bill:
I asked the BNSF Bridge Engineer about this, and he said the trusses
were replaced in 2000 and 2001. The five 140' double track thru
trusses were replaced with beam spans over the land portion, and two
190' double track thru trusses over the river.
As I recall, the track centers were very narrow on the original
trusses, perhaps originally 12', and later the tracks were shifted
out slightly to provide better track centers at the expense of
reduced side clearance. All of this fits with the necessary
modification of the bracing that Steve Holding talked about.
The trusses were old also, as I believe they were put in before
1900. The floor system of the old trusses fatigued out, and the
Bridge Engineer said they could not keep up with broken "stringer to
floorbeam connection" angles and broken bolts in those connections.
The trusses were also pin-connected, and the pin joints were worn
from years of use, and from damage to the truss members from being
hit by wide loads.
Regarding the signal bridge at Albia, if you recall any specific
details, such as the pedestal type, or location of the inspection
ladder, I would appreciate hearing about it.
Glen Haug
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