Residual performance of macro-synthetic fibre reinforced concrete for sleeper applications

Prestressed concrete is the most extensively used material for railway sleepers (~75%), with the increased weight providing greater track stability suitable for high-speed traffic on modern tracks. Although the improved operational performance (i.e. higher bending strength & service life) also justified such adaptation of prestressed concrete over timber and steel sleepers, constantly increasing operational demands are now precluding them from fulfilling all railway industry requirements. These limitations typically include material deterioration, corrosion and premature cracking that may occur, thereby reducing the sleeper’s performance capacity, increasing maintenance frequency and associated costs. Therefore, macro synthetic fibre reinforced concrete (MSFRC) is suggested as a reinforcement technique owing to its improved post-peak flexural capacity, ductility and crack-arresting properties. In such scope, the residual behaviours of MSFRC are investigated by a series of material- and structural-scale experiments towards optimising (i.e. in terms of fibre dosage and fibre type) the MSFRC sleepers for future railway applications. Moreover, this paper will present the operational benefits of MSFRC over conventional prestressed concrete sleepers, critically comparing the residual capacity, stiffness and toughness.