Methodology for Evaluating the Load-Carrying Capacity of Standardized Pontoon Bridge Structures

Abstract

Purpose. The objective of this study is to develop approaches for the objective investigation of the inventory structure of the NZhM–56 floating railway bridge. It involves selecting a computational model for the floating bridge to facilitate further substantiated research into load-carrying capacity and formulating recommendations for the deployment of NZhM–56 equipment to accommodate railway, vehicular, and tracked loads. Methodology. Variational modeling of NZhM–56 floating (pontoon) bridges using diverse configurations (varying in length and number of pontoon supports) for analysis via the influence line method. Analysis of the obtained results and substantiation of the bridge crossing computational model proposed for further research. Application of software implementing the Finite Element Method (FEM) to conduct the investigations. Findings. Development of approaches for recalculating the load-carrying capacity of inventory floating (pontoon) bridge systems using the finite element method. The study identifies the specific length and assembly configuration of the NZhM–56 floating bridge that exerts the greatest impact on internal forces generated under live loads. This configuration is selected for further research and for providing substantiated recommendations regarding live load passage. Furthermore, the most critical (unfavorable) scenarios and positions for live load placement have been proposed to investigate the stress-strain state of the structure. Originality. The scientific significance of this work lies in the selection of
a methodology for recalculating the load-carrying capacity of floating (pontoon) bridge systems, specifically focusing on the NZhM–56 bridge. A comprehensive investigation is conducted into the relationship between the critical length, the assembly configuration of the NZhM–56 bridge, and the magnitude of internal forces generated under live loads. Furthermore, the research focuses on the specific behavior of the transition section of the pontoon bridge, analyzed both as an independent subsystem and in its structural interaction with the river (main) span elements. Practical value. Definition of approaches and methodologies for recalculating the load-carrying capacity of inventory floating (pontoon) bridge systems, necessitated by contemporary challenges. The research is aimed at ensuring the safe passage of temporary railway, tracked, and wheeled loads over the NZhM–56 floating bridge. Furthermore, the study identifies specific features of investigating floating bridge systems through the application of software implementing the Finite Element Method (FEM).