Splice connection detail: help

[longisland]

Hi,
I need to design a bolt splice to connect two circular hollow sections. The member is a column taking moment & compression. I'm thinking of welding an end plate to the section & connect the two members with 4 bolts; the splice will be in the midsspan of the member(least moment). The member is 1 meter length supporting a pipe bwidge (lattice truss) spanning 30m. Any suggestion on the thickness of the end plate & the length of the bolt? Since the bolts are holding the end plates, The length will be only 75mm if 10mm plate is used.

thanks

 

[ishvaaag]

The thicknesses of plates and diameter of the bolt will be derivable form a safe assumption of the loads acting. The nut being sold for the bolt will be normally able to extenuate its capacity in tension. So shims, washers also affect the length, and decide what excess to have (normally the minimum, will make less the installers less prone to leave the thing less pressed than required). Consider if you use some holding clip device or point weld etc.

 

[ishvaaag]

... from a safe assumption...[was the intent]

Also, only in rare circumnstances I would be considering diameters of bolts no t in the range of the thickness of the plates, more or less.

 

[longisland]

Hi,
Thanks for the response. the reason for bolt connection is we plan to place the truss onto an existing pier of 3 by 4 ft. I'd consider clipping. Welding is impossible.The shear is minimal along the plate surface. I just need to make sure the axial compression load is transferred to the support.

 

[diamondjim]

I would use some dowel pins to help with the
side shear forces resulting from the assumed
hoop stresses.