Deflection and First Natural Frequencies of a Regular Arched Truss Oscillation

The dependences of the first four frequencies of natural oscillations of a planar regular truss of the thrust type are obtained numerically. A model is used in which the mass of the truss is concentrated in its nodes. The Maxwell–Mohr formula is used to calculate the rigidity of the truss. For the first frequency, an analytical dependence on the number of panels is derived by the induction method using a simplified version of the Dunkerley method in the Maple computer mathematics system. Good agreement with the numerical result is shown. An analytical dependence of the static deflection of the truss on its dimensions and load is obtained.