Real-Time Monitoring And Early Warning Systems For Subgrade Settlement Of High Speed Railway In Service Period

The performance deterioration of the local subgrade of high speed railway in service period under the dynamic load and natural forces leads to subgrade settlement after acceptance, which poses a great threat to the long-term operation safety. The purpose of this paper is to improve the security technology of high speed railway. Based on field investigation and numerical analysis, the mechanism and patterns of subgrade settlement and the influence law of high speed driving safety affected by subgrade settlement were briefly studied. Taking into account the different patterns of subgrade settlement, the key parameters of ballastless track-subgrade structure, settlement safety limit value and three levels of the critical risk value were proposed to high speed railway subgrade, based on the train-track-subgrade system dynamics theory. The RAMS real-time monitoring and early warning systems for subgrade settlement have been discussed to set up with fiber optic sensing technology, distributed information processing and wireless transmission technology, and multi-module application software, based on the safety limit value and three levels of the critical risk value. Moreover, innovative real-time monitoring equipments have been developed. This research can provide technology and equipment for administrative departments of railways to take charge of subgrade state.