Calculation of Thermal Stresses of Cast Iron Tubbings Under Fire Effect
Publication Name: Advances in Transdisciplinary Engineering
Publication Date: 2024-01-01
Volume: 59
Issue: Unknown
Page Range: 431-437
Description:
This article builds on our existing knowledge of the heating of cast iron tunnel linings and deals with the structural analysis of tunnel linings under fire exposure. Due to space constraints, we do not address the issue of sizing for earth pressure and surface loads. Since the analysis of thermal stresses due to restrained deformations is insufficient in the available literature, we will try to complement the existing theoretical knowledge with the knowledge provided by the relevant standards for cast iron lining of tunnels. In addition, we will try to add our own individual reflections to the theory where we have identified gaps. The theoretical summary is compiled in such a way that it is easily transferable and applicable to everyday practice. Our finite element analysis shows that the value of the embedding factor has a small effect on the development of the axial constraint stresses in the tunnel direction, while in the ring direction has a significant effect. In all cases, stiffer embedding results in higher stress values. In all cases, the ring direction compressive stresses are lower than the longitudinal stresses due to the deformation of the tunnel ring. There is no literature data available on the value of the compressive stresses, so we have tried to provide some indicative data in tabular form for the profession. The solution adopted and the values proposed are based on the authors' individual ideas and are not the result of an accepted professional consensus. In all cases where more precise data are required, it is recommended that a more detailed study be carried out. Finite element modelling can provide the necessary support for designers and experts.
Open Access: Yes
DOI: 10.3233/ATDE240576