PSI - Issue 72

Boris Folić et al. / Procedia Structural Integrity 72 (2025) 278 – 285

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Fig. 7. (a) Distribution of hydraulic presses. The uplift force in the arch can be determined as a force close to the normal arch force or as a force to be applied to a curved parabolic cantilever supported on the formwork. During the introduction of the normal force into the arch by the presses, the friction force appears as a reactive force in the arch, at the lower end between the RC arch and the formwork. The friction force is perpendicular to the force of its own weight, which acts on the formwork at a certain angle The intensity of the frictional force solely depends on the intensity of the normal force and the friction coefficient. Friction along the arch can be considered as a distributed horizontal force in the direction of the axis of the arch, but in the opposite direction to the force coming from the press. Since the frictional force has an eccentricity in relation to the neutral line, it also creates a distributed moment along the rod. Roughly, a rod can also be solved as a polygon.

Fig. 8. Longitudinal and cross section of larger (span 390 m) and smaller arch of bridge Krk, by Pržulj (2014)