Re: [CBQ] burlington bridge fixed spans

[Kenneth Martin <kmartin537@surewest.net>]

In response to Bill's post a little historical perspective.

 From the magazine "Engineering and Contracting" Vol 30  page 380

"Weight of the Burlington Bridge of the C. B. & Q.

In 1890 a double track steel railway bridge was built across the  
Mississippi River, at Burlington, for the C, B. & Q. R. R., to  
replace a single track iron bridge built 22 years before. The 6 spans  
of 250 ft. each, weighed 3,340 lbs. per lin. ft. The draw span of 363  
ft. weighed 3,980 lbs. per lin. ft. The bridge was designed to carry  
a moving load of 6,000 lbs. per ft. of double track structure (3,000  
lbs. per ft. of single track), this load being increased 50% in  
estimating the variable effect of a moving load. The cost of  
engineering was 5% of the total cost of piers and superstructure."

Pretty good to be running modern diesels over it 120 years later.

Ken Martin




------------------------------------

Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/CBQ/

<*> Your email settings:
    Individual Email | Traditional

<*> To change settings online go to:
    http://groups.yahoo.com/group/CBQ/join
    (Yahoo! ID required)

<*> To change settings via email:
    CBQ-digest@yahoogroups.com 
    CBQ-fullfeatured@yahoogroups.com

<*> To unsubscribe from this group, send an email to:
    CBQ-unsubscribe@yahoogroups.com

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/