Arched design with all other conditions being equal, will always be stronger, safer and cheaper structures of other types — especially when the arc itself consists of rods, working only on tension and compression. At the time, it was appreciated by the famous mechanic Kulibin, who created a scale model of the arch bridge, which was supposed to connect the banks of the Neva. The original arch design, suitable for the creation of greenhouses, conservatories, sheds, garages and other structures, have managed to create a reader of our magazine from Novgorod S. Y. Makurin. The module of such a set represents a Central design consisting of 240 wooden rods (rails) with cross-section 20×50 mm and a length of from 0.5 to 1 meter (volume of the material is 0.2 cubic meters). The module area is 15 square meters. Docking these modules, you can get the arch structures of any size and different configuration.
The frame of the arch is assembled from relatively short rods (rails) with cross-section 20×50 mm, the ends of which are chamfered so that between the mating terminals formed angle of 162 degrees. This angle provides a chamfer, the legs of which are respectively 50 mm and 1 7 mm Only for each of the modules, it is necessary to prepare 60 rods 16 of various sizes in accordance with table No. 1. You must also prepare 16 bolts with thread M5 or MB and 150 mm in length and 5 bolts (also threaded M5 or MB) with a length of 90 mm with an appropriate number of nuts and washers. Also need a wooden strip with the size 20x50x50 mm.