Effect of design rail cant on concrete crosstie rail seat pressure distribution

Previous research has focused on the effect of rail cant on rail wear and wheel/rail interaction, indicating that a steeper rail cant results in increased wear on rails and wheels. However, no research has investigated the effect of rail cant on the crosstie rail seat pressure distribution. Past research at the University of Illinois at Urbana-Champaign (UIUC) looked into the effect of negative (reverse) rail cant on pressure distribution across the rail seat utilizing matrix-based tactile surface sensors (MBTSS) on artificially created rail seat wear profile at TTC, Pueblo. These results showed that the pressure distribution became more non uniform with increasing negative rail cant. This paper looks into the effect of 'design' rail cant on pressure distribution across the rail seat. Static tests were carried out on 1:30 and 1:40 cant crossties imparting a predefined sequence of vertical and lateral load combinations. MBTSS and potentiometers were used to measure pressure distribution and rail rotation respectively. The 1:30 cant distributed load more evenly than 1:40 cant at lateral to vertical force ratios greater than 0.4. The two rail cants did not show significant differences in the values of average pressure, contact area, or rail rotation.