Field statistical and finite element analysis of rail squats

• Field results are statistically analyzed and effects of different parameters on squat growth rate investigated.
• A 3D finite element model is created and effects of some parameters are assessed.
• Both FEM and statistical studies confirmed sleeper type and curve radius affect squat growth rate.
• The correlation between field results and FEM validates results obtained from FEM.

In this paper, squats on 262 km of Australian railway track have been statistically investigated. Data from more than 4900 squat occurrences has been collected. At each point, rail type, rail, sleeper type, the curve radius and rail direction are recorded as fixed parameters. A linear mixed model has been used to statistically identify the parameters and parameter combinations that are more likely to lead to the occurrence of squats and results are compared with those from a 3D finite element model. Results show that squats are more likely to occur in sharper radius curves due to higher lateral traction and at locations with a softer foundation due to the elastic foundation effect.