Calculation of the load-bearing capacity of a wood-wood joining system adapted to digital and democratized manufacturing

CAD/CAM technology applied to wooden structures means that traditional joining techniques, rather than metal-fastener-based systems, can now be industrialized. The development of the "Spatial Masterkey" system manufactured with a 3-axis CNC milling machine is presented. The system democratizes traditional joining techniques. It is designed for the construction of lightweight roofs, based on articulated joints with 50x50 mm section bars, working under traction and compression. A test campaign involving 6 different trials was proposed for the evaluation of the behavior of the different nodes. Satisfactory practical results were obtained in relation to the estimated theoretical values. Tensile and compressive tests on the horizontal/vertical bar nodes yielded higher results than the calculated values (8.50 kN before failure). With regard to the tests on the diagonal bars, cylindrical doweling reinforcements were required, which increased the resistance capacity by almost 130%. Future lines of research that can be pursued within this field are also proposed.