Experimental study of the gap between track slab and cement asphalt mortar layer in CRTS I slab track

Abstract

Gap exists in the interface of cement asphalt emulsion mortar and CRTS I track slab universally, which is more severe at four corners than other parts of the track slab. In this work, the temperature and elevation of CRTS I slab track with and without rail were measured continuously to study the influence mechanism of rail on the gap. The results show that the alternating temperature gradient of track slab is the main reason that causes the gap, and laying rail can efficiently decrease the gap size in the slab track without rail. Compared with the slab track without rail, the maximum elevation occurred at the corner, the maximum gap width and the maximum gap depth of the slab track with rail laid were decreased by 0.45 mm (25.7%), 0.75 mm (46.6%) and 9.5 mm (59.4%), respectively; meanwhile, the disqualification ratio at corners was reduced to 5.9%, which is 50% less than that of the track without rail. When elevation mismatch occurs in adjacent track slabs, a gasket should be placed at rail-bearing bed below the track slab in order to avoid the lower slab being dragged up by the higher slab and the further occurrence of new gap.

Identification of Temperature-Induced Deformation for HSR Slab Track Using Track Geometry Measurement Data

“…Warping deformation starts with initial misalignment/upward curl during the construction phase and usually occurs during high-temperature seasons [16]. Under the aforementioned temperature effect, the top surface of slabs will elongate, while the bottom will compress [16,20,26,39]. As a result, slab warps upward due to eccentric compression.…”

“…To investigate how track slab damages initiate and how they affect vehicle-track system dynamics and track irregularities, previous studies carried out numerical simulations [3][4][5][6][7][8][10][11][12][13][14][15][16], full-scale tests [9,[17][18][19], and field tests [15,20,21]. These studies shed some light on repair works for defects, slab maintenance, and life-cycle management of slab track.…”

“…A straightforward method of damage detection for slab track is regular visual inspection or non-destructive testing (NDT) methods [20][21][22][23][24][25][26][27][28]. The NDT techniques are powerful in damage detection for concrete structures, especially in structural health monitoring of bridges [29][30][31].…”

Experimental Study of the Influence of Extremely Repeated Thermal Loading on a Ballastless Slab Track-Bridge Structure

“…A three-dimensional finite element model of the interlayer shear failure of the CRTS-II slab ballastless track was established, and the mechanism of the interlayer shear failure of the track and the effect of the interfacial damage on the dynamic structural performance was analyzed. He Chuan et al [23][24][25] used the finite element method to simulate the interlayer interface relationship of the track structure by using a contact element and studied the influence of different locations and sizes of the interlayer gap on the mechanical properties of the track structure.…”

“…20 25 30 35 40 Track slab strain at fixed end section (με) Track slab strain at mid-span section (με) slab strain at the sliding section (με) Load (kN) Before thermal test After thermal test (a) Fixed end section (b) Mid-span section (c) Sliding end section…”