Evaluation of humped slab track performance in desert railways

Abstract

The movement of sand dunes in desert railways has various harmful effects on conventional ballasted tracks. Ballast layer solidification and line closure due to the retention of sands are major problems in such areas. In this study, a new superstructure called ‘humped slab track’ is introduced which can obviate the main problems for desert railway tracks to a significant extent. This system applies the main advantage of the ballastless track which is theballast layer's elimination for avoiding the filling of ballast voids via sand dunes. Moreover, the rail seats in this superstructure were elevated above the slab level by means of reinforced concrete protuberances called humps. Hence, the transmission of sand dunes occurred through the transverse channels between the humps and beneath the rails. To demonstrate the efficiency of the proposed system, several multi-phase fluid simulations (involving solid sand particles and air) were accomplished using the computational fluid dynamic method. The results obtained for the maximum sand flow conditions show that the ballasted track needs to be closed after a very short time whereas the humped slab track is capable of enduring considerable sand flow conditions without any need for line closure.