Tensar’s “Keeping You in the Know” video series is a Q&A influenced campaign. Here in its third video, Stabilisation Systems expert Mike Horton (Tensar International Limited) tackles the question: “What evidence is there that TX190L outperforms biaxial geogrids in track ballast?”
“Tensar’s geogrids have been used to stabilize rail ballast and sub-ballast for the last 30 years,” he says. “[These] geogrids are a cost-effective way of increasing trackbed stiffness and of establishing and maintaining good track geometry.”
He discusses the interlocking effect of a geogrid within track ballast and the resulting long-term stabilization of the system. He cites research that has revealed how geogrid-stabilised railway tracks can double or even quadruple the time between maintenance.
Regarding whether to use triaxial or biaxial geogrids in this stabilization application, Horton notes research from England and the Czech Republic that studied this question.
“Results show that using TriAx® means sleeper settlement is reduced further, when compared with the same track bed including a Tensar biaxial geogrid,” Horton says, “And trackbed life can be up to 10 times longer than non-stabilized ballast.”
It also showed that ultimate tensile strength was not a useful way to predict track bed performance. This echoes what Johnathan Cook addressed regarding tensile strength in the first video in Tensar’s “Keeping You in the Know” series.