The article presents a theoretical description and procedure for calculating the three-hinged arch parabolic outline. The technique of creation of the universal program in a computing complex of Mathcad for various options of vertical loading is in detail stated. The method of calculation of a three-hinged statically determined arch is considered in detail. The order of design calculation is given in the article. The technique of the automated creation of diagrams of internal power factors of an arch design is offered. A detailed description and analysis of the design scheme of three-hinged arch is given.
Keywords: three-hinged arch, statically definable arches, arched structures, parabolic outline, diagrams of internal power factor