There are many forms of steel structure space frame nodes. According to the node connection method, there are the following forms for reference:
(1) Welding connection. It is divided into butt weld connection and fillet weld connection.
(2) Bolted connection. It is divided into tension high-strength bolt connection and friction type high-strength bolt connection.
According to the structure of nodes, there are mainly:
(1) Cross steel plate joints. It is developed on the basis of plane truss joints. The rods are composed of angle steel. The connection between the rods and the gusset plate can be made by fillet welds or high-strength bolts.
(2) Weld the hollow ball node. It consists of two hot-pressed hemispheres and then butt welded to form a hollow sphere. The rod is welded on the spherical surface, and the welding seam connecting the rod and the spherical surface can be a butt weld or a fillet weld. The rods consist of steel pipes.
(3) Bolt ball joint. It connects the rod with the solid ball through bolts, sleeves and other parts. The rods consist of steel pipes.
(4) Direct junction nodes. It is to directly weld the end of the web rod (branch pipe) in the mesh frame into an intersecting surface and then directly weld it on the wall of the chord rod (main pipe). It is also possible to weld one direction chord to the wall of the other chord. Such nodes avoid the use of any connectors. Save the amount of steel used for joints, but require high assembly accuracy. The rod is composed of steel pipe or square pipe.
After years of structure engineering practice, the most commonly used joint forms are welded hollow ball joints and bolted ball joints.