Camber-Length Ratio

[etabs2002]

If girder got camber 2" how much that will be change lenght of the girder.
How to calculate?

 

[JStephen]

Assume the centerline length along the arc stays constant. With a small camber, the change in length should be fairly negligible.

Example: With a 14,400" rolling radius and a 480" long beam, I get a 2" camber and a change in length due to curvature of 0.022".

 

[kxa]

How did you come up with 14400" for the radius? I get R=1200". Anyway, I agree the length change is megligible. Besides, once it is installed it will straighten out somewhat.

 

[wannabeSE]

kxa,
One way is to use Pythagorean's theorem: radius²=(½ span)²+(radius-camber)² This reduces to radius=[¼span²+camber²]/[2camber].

The arc length = 2radius*asin(½span/r)