This dramatic joinery combination hails from temples and structures throughout Asia. If you have a four sided structure and need a clear span without the traditional tie beams over head or just want to add a cool feature to a frame, then this is the answer.
The purpose of this joinery combination is to resist the outward thrust that the hip (blue) puts into the corner joint. It consists of a dragon beam (yellow) and the dragon brace (purple). The dragon beam acts as a tie beam, taking the outward thrust of the hip and transfers that load into the dragon brace. Which in turns transfers it to the plates. Structural screws are used throughout to aid in installation and its overall strength.
I am not sure how much it may have been used in Asia (I haven’t seen it in any books), it was common historically throughout the English settled areas of the US and Europe for hip roof assemblies. However, as you have drawn it, it will handle only very low outward thrust. Traditionally, the foot of the hip rafter was mortised into the dragon beam which will handle much greater loads than as it is drawn. Your version relies heavily on screws. I may be old fashioned but I think if you are going to tout its advantages, then it should be drawn as it was done historically, or at least mention that it has been modified from its true form.
For an illustration of it, see Richard Harris’s “Discovering Timber Framed Buildings” page 86.
Thanks for your thoughts, Jack, I will dig up my copy of it to check it out and research my Asia comment. I have the model complete of a dragon beam assemble similar to the one you described, it was going to be a new post, but perhaps it would be better to include the images/text in this post give a better overview of the joinery options. I agree about the low outward trust, it was designed for a 12×12 frame.