Investigations on the shearing performance of ballastless CRTS II slab based on quasi-distributed optical fiber sensing

Abstract

With the continuous development of high-speed railway technology, there are higher expectations for train operation and running safety. Shear failure is the main form of damage to the ballastless CRTS II slab as an essential part of the ballastless track system, and its interlayer shearing performance and damage mechanism play an important role in ensuring railroad safety. This paper employs quasi-distributed optical fiber technology to investigate the force characteristics, ductility performance, and damage mechanism of ballastless CRTS II plate in shear failure. The influences of shear reinforcement on the shear bearing capacity of ballastless track structure are also investigated. It is concluded that shearing force in each layer of the CRTS II ballastless track exhibits obvious nonlinear characteristics, and the introduction of shear reinforcement can improve the seismic performance. The quasi-distributed optical fiber sensing has good performance in the field of ballastless track monitoring, which compensates for the limitation that traditional monitoring methods are difficult to be used in concealed CA mortar layer in long-term service and provides reasonable recommendations for ballastless track design and subsequent maintenance.