Research on analytic solutions of intersecting line at joint of square and round tube on space tube-truss structure

The Joints of space tubular truss structure have various shapes, as well as decent styles. The intersecting lines are formed of different schemes, especially many benefits of joint on square and round tube have drawn increasing attention of researchers. So far, little researches on the lofting problem of intersecting lines for square and round tube, no related theory about it are present. This article derived analytical solution of space equations of intersecting lines at joints of Y-type and N-type square and round tube. Further, the coordinate form of arbitrary point on intersecting lines are obtained, and also put forward corresponding simple processing methods for the problems of intersecting lines of other joints on square and round tubes Computer program is combined to make lofting automatically, to improve work efficiency and accuracy of lofting, and to save material. The conclusions can be used as practical guidance for manual graphics, computer graphics, numerical control programming, fabrication and installation, and metal plate cutting in construction projects.