Numerical analysis of geogrid contribution to railway track reinforcement

¹ DEC, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Lisbon, Portugal
² IDMEC, Instituto Superior Técnico, Universidade de Lisboa, Lisbon, Portugal
³ LNEC, Laboratório Nacional de Engenharia Civil, Lisbon, Portugal

^* Corresponding author: zdim@fct.unl.pt

Abstract

In this work, influence of geogrids on overall stabilization of railway tracks is studied numerically. It is expected that by geogrids implementation significant reduction in the downward propagation of stresses will be obtained, which consequently should assure more resilient long-term performance. In this first approach, however, only added value to the confinement level of the ballast layer is analysed, by evaluation of lateral deformations. A case study is related to a part of the Portuguese railway network. The track and the passing vehicle are modelled in commercial explicit dynamics software LS-DYNA. Firstly, the model is validated by comparison with experimental data. Then a fictitious scenario of the same track with a deteriorated region which is further rehabilitated by the geogrid placement is analysed. Different situations are compared in terms of lateral and vertical displacements at several levels, but for simplicity only rail deflections are shown here.