Heavy-Duty Splices

[Peter Miles]

It's a bolted joint, not rivited, and the material is several inches thick so it isn't really sheet metal, but the following two pictures really show that you can make a bolted or rivited joint that can transfer the stresses and loads of just about any structure.

This is a column in what could be described as an underpass in Chicago. This is in an area where several of the streets are double-decked and this holds up the top-level of the street.



There are 104 separate bolts visible in this splice. That is a lot of work.


On a lighter-duty scale, you see similar rivited or bolted joints in bridges, elevated railroad structures, etc. throughout the city.

On a very much lighter scale, similar bolted structures are used to put together the fuselage frame on my BD-4 airplane, which is composed primarily of 0.020" - 0.064" aluminum angles bolted together.

Since that may have been made many years ago, would that same splice be welded in today, maybe using the sub arc process?

[Gene_Olson]

Since that may have been made many years ago, would that same splice be welded in today, maybe using the sub arc process?

I don't think so.

These are field joints and speed is important.

Those bolts now have a built in torque test. They are alloy steel, and spec.ed to the hilt. I am told they come with a smaller allen wrench/or torx type end that extends beyone the threads.
The "allen" end is necked down where it meets the bolt so that the shear value is the optimal torque value for the bolt/nut combo.
They are inserted from the back, and the wrench mates with both the allen end of the bolt and the nut at the same time. The nut is tightened until the allen end shears off.

Wham bam, one shot.

G