Thanks for checking out my post- I work at a launch facility, and we have light fixtures around the site that have proven to be poorly designed by the manufacturer. Multiple fixtures joints have failed over time due to lack of proper structural support - My goal is to add sufficient supports to these fixtures without over-complicating things, and then backing up my corrective action with calculations. The largest force acting on these fixtures is from the rocket blast, which I assumed to act as a blast wave at a 45-degree angle to the top surface of the fixture (based on the fixture location). I also used wind speed and fixture weight as additional forces, and then I calculated the resultant moment acting on the joint. From that, I simply calculated the reaction moment on the other side of the joint, and then determined the force acting on the new bolt I plan to add for support. See attached for my calculation. As you can see, my final shear stress on the bolt was found to be 311 ksi, which seems way too large to be correct.. I was pretty conservative in this approach, but I still would not expect an answer on this order of magnitude. Any help would be extremely appreciated.