Istrazivanja i projektovanja za privreduJournal of Applied Engineering Science

This paper presents the numerical application of a form-find two-pin arch shape with constant cross-section made of concrete. This investigation is carried out for arches with any span to height (L:h) ratio and any ratio of uniformly distributed load (UDL) to self-weight (SW) in which the geometry is a function of loading. The form-find arch shape is the one comprising only axial forces named momentless arch in this paper. The contribution of such a form-find arch is shown in a case study firstly through comparing its deflection with the most favourable arch shape under UDL:SW > 1 which known as parabolic form. Secondly, the fi rst failure of arch cross-section for form-find arch is evaluated against parabolic one subjected to the same permanent load. Results show the maximum vertical displacement of the form-find arch to be almost half of the maximum vertical displacement of its parabolic equal. To have the same maximum displacement, the thickness of the form-find arch could be reduced to half of its initial value leading to mass reduction. Furthermore, the former arch shows the first cross-sectional failure for 24% higher vertical displacement at the arch crown compared to parabolic arch.