Study of the steel pipe stress-strain state in the embankment body, with the account of the base soil creep

Abstract

The construction of new railway lines in the Far North regions poses a number of challenges for scientists, such as overtime behavior study of the various structures included in the railway infrastructure like bridges and culverts. This is because the frozen base soil has viscoelastic properties, which are fraught with the high stresses and deformations development in these structures over time. The article presents the study results of the steel culverts’ behavior located in the embankment body, with the account of the base soil creep. The base soil is considered frozen. Culverts of different diameters are considered based on data from the Obskaya-Bovanenkovo railway line (Yamal Peninsula). The problem was solved on the basis of the finite element method (FEM) based on the MSC Nastran software package. An assessment was made of the change in the stress-strain state of these structures in time on the time segment [0, 1000 days] under the characteristic dead load. The influence of a number of parameters, namely the pipe diameter and the frozen soil temperature, on the steel pipe behavior over time has been studied. It is shown that even a slight increase in the frozen soil temperature (by one degree Celsius) leads to a noticeable increase in stresses and strains in the steel pipe, due to the base soil creep. Reducing the pipe diameter (from 3.4 m to 2.6 m) also leads to an increase in stresses and deformations in the pipe body over time, but to a much lesser extent compared to an increase in the base soil temperature.