Simulation of thermal load distribution in portal frame bridges
Journal article, 2017

Uneven exposure to e.g. solar radiation can cause temperature differences between various structural parts of a bridge, which leads to tensile stresses if the parts cannot move freely. In this study, thermal simulations and stress calculations on a model of a portal frame bridge are performed with the aim of evaluating the temperature difference between the bridge parts. Factorial design is used in a parametric study to determine the influence of different factors on the temperature difference and the largest reasonable temperature difference obtainable for the chosen weather data. The study shows that the quasi-permanent temperature difference between parts which is proposed by Eurocode 1 is overestimated, causing tensile stresses in the transverse direction to be exaggerated significantly. Using the design method proposed by Eurocode 1 is therefore likely to overestimate the required reinforcement in crack width limit design, which in turn would lead to unnecessary costs and environmental impacts. The results also indicate that the temperature distribution within the bridge is different from what is given in Eurocode load cases, and consequently, the largest tensile stresses appear in other areas of the bridge. A simplified temperature distribution is therefore investigated and shown to give similar results as the detailed thermal simulations.

Restraint stresses

Thermal simulations

Parametric study

Portal frame bridge

Thermal load

Eurocode

Author

E. Gottsäter

Lund University

Oskar Larsson Ivanov

Lund University

M. Molnár

Lund University

R. Crocetti

Lund University

Filip Nilenius

Chalmers, Civil and Environmental Engineering, Structural Engineering

Mario Plos

Chalmers, Civil and Environmental Engineering, Structural Engineering

Engineering Structures

0141-0296 (ISSN)

Vol. 143 219-231

Subject Categories

Building Technologies

DOI

10.1016/j.engstruct.2017.04.012

More information

Latest update

3/2/2018 9