PSI - Issue 72

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ScienceDirect

Procedia Structural Integrity 72 (2025) 286–293

12th Annual Conference of Society for Structural Integrity and Life (DIVK12) Accidental load on Žeželj bridge and analysis of soil caisson bridge interaction Boris Folić a, * , Miloš Čokić b , Željko Žugić a, * a Innovation Center of Faculty of mechanical engineering, Kraljice Marije 16, Belgrade, Serbia. b Termoenergo inženjering , Bulevar Kralja Aleksandra 298, Belgrade, Serbia. Abstract This paper shows the influence of exceeded loads on foundation of caisson Žeželj bridge (ŽB) in Nov i Sad. The exceeded load occurred at the beginning of the 60s of the 20th century, that is, only a few years after the facility was put into operation. A long span arch AB bridge (or PC) is not designed in a plain, unless there is solid rock on the shore t o support it. Of course, Žeželj knew about the foundation problems on the banks of the Danube in the vicinity of Novi Sad, where the soil is usually loess, clay, alluvial sand and gravel, so he envisioned immovable supports on caissons on the banks and in the center of the river. It is known (at least to the older generations) that Žeželj first performed the so -called prestressing of the soil, namely behind the caisson towards the coastal part, the soil was replaced, and thanks to the AB diaphragms that were located between the caisson and the soil, passive resistance was activated with the help of hydraulic presses. Therefore, with that prestressing, the soil consolidation correction was executed, i.e. all horizontal movements of the supports (caissons) that would naturally occur and thus endanger the building, were carried out during construction, before commissioning (this means the sum of horizontal movements including the flow of concrete). This made the bridge stable with immovable supports, or so it wa s thought. A few years after being comissioned, ŽB was subjected to a flood wave and considering that the banks were not adequately supported, the integrity of the bridge was threatened. During the flood, there was an urgent intervention with ballasts, probably piles of rocks, in order to protect the bank from erosion and ensure the immobility of the supports. In this paper, the interaction of the structure and the caisson with the ground was analyzed through possible stages of loading. Different levels of influence and possible adequate combinations were treated: passive resistance of the soil and sliding in the coupling as well as the thrust force on the caissons. The modern project in the Radimpex Tower will not be treated here, but exclusively the calculation methods that were current in the late 1950s and early 1960s.

* Corresponding author. Tel.: /. E-mail address: zzugic@gmail.com * Corresponding author. Tel.: /. E-mail address: boris.r.folic@gmail.com

2452-3216 © 2026 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of Aleksandar Sedmak, Branislav Djordjevic, Simon Sedmak Dr. Simon Sedmak, ssedmak@mas.bg.ac.rs, Innovation Center of Faculty of Mechanical Engineering, Belgrade, Serbia 10.1016/j.prostr.2025.08.105