Timber nailer on Steel beam

Not sure of the forces you anticipate - but have seen heavy doses of wood construction glue used. Clamp as you go.

Also - much easier and cheaper(than welding) is to place bolts on opposite sides of web as you march down the beam length. Say at most 16'' oc. - 24'' might be OK. Just drill through the wood and steel at same time. NO welding required.

Also have seen powdered actuated anchors used. By far the quickest and easiest meth.

Have fun..

I was thinking about placing bolts on opposite sides of the web, but I couldn't find any info on sizing these either. Most likely this is the route we will go, however, I would really like to see some type of reference talk about this type of connection before I specify it.

Design them the same way you would design shear connectors for composite construction, although your studs wouldn't require the same strength as needed for composite construction.

I don't know "powdered actuated anchors", but with a stud welding gun you can easily achieve what you want/need. very easy, fast, and no actual "welding" required. Also no need to chamfer the bottom end of the through hole (through the wood); as there's no weld around the studs.

Keep in mind that these bolts are not high strength A325's but rather simple bolts used for wood construction - the loading/design of the weld of the bolt to the beam won't be the critical failure mode but will probably be the bolt/head shear in the wood or pull out.

Also, we've used self-tapping screws for this rather than bolts - look at Hilti's product catalog as they have some screws that can work.

And don't forget to check possible uplift

Some thoughts:

1. If you are using top hung joist hangers off the plate, which it does not look like you are, extend the plate to the edge of the seel beam flange.

2. These threaded studs react in bearing against the nailer for shear. So, the max shear is directly related to the diameter of the bolt bearing parallel to grain, or perpendicular to grain, depending on the force direction, and subject to the allowable forces for bolts in the NDS.

3. You might want to countersink the bolt and nut heads into the 2X plate and paint with a good wood preservative.

4. If this is an outdoor application, the plate wants to be pressure treated - real bad!

Mike McCann
MMC Engineering

If you are just attaching the nailer for decking only and the beam flange isn't too thick you may want to consider self-tapping, self-drilling screws with wings. (Simpson TB screws and Hilti has an equivalent product). When I attach like this, I design the attachment for uplift and any diaphragm shears that are transferred through the connection