Question about spreader beam unbraced length

[CTW]

I'm reading David T. Ricker's "Design and Construction of Lifting Beams" and read on page 153 that "The unsupported length of a lifting beam is the length between the outermost lifting holes." Why wouldn't the unbraced length be the entire length of the beam regardless of where the lifting points are located?

 

[desertfox]

Hi CTW

If you consider the lifting beam to be a three point lift ie:- the 2 lifting holes to be the simple supports and the load being lifted in the middle and draw the shear force and
bending moment diagrams you will see there is no bending moment or shear force outside of the extreme lifting holes.

regards desertfox

 

[dlew]

CWT,

For a more detailed discussion of a spreader beam unsupported length see Thread 507-38270.

 

[JAE]

Here's a direct link:

Thread507-38270

 

[flamby]

As desertfox already stated, the design length can not exceed the length between the farthest supports. The length beyond these supports does not take part in any structural computaion apart from just being there as a dead weight.

 

[CTW]

Thanks for your replies. They have been helpful.