Study On Damage Behavior Of Wide Juncture In Crts Ⅱ Slab Track

The damage of wide juncture in CRTS II slab track are very common. It will be away in winter and be arch up in summer, which may threaten the driving safety when it became serious. The wide juncture as the key part of CRTS Ⅱ slab track, currently lacking systematic research of its damage mechanism. This article is specific to the damage of wide juncture, using the finite element software and concrete damaged plasticity model to research its damage mechanism, the main contents and conclusions as following:(1) In view of the construction process of the wide juncture, analysis the influence of track slab and the narrow juncture concrete after longitudinal tension. The results show that after longitudinal tension, the stress of longitudinal rebar is uneven, mainly concentrated in the tension region, and the stress of longitudinal rebar in the inside of track slab is small; The squeezing effect to the narrow juncture concrete is not obvious; By comparing whether pouring the narrow juncture concrete before longitudinal tension, found that whether pouring the narrow juncture concrete nearly don’t influence the stress of the longitudinal rebar and the track slab; In order to simplify the construction process, it is recommended that pouring the concrete of wide juncture after longitudinal tension.(2) In the place of wide juncture, the occupied space of the six tensioning lock is larger, when suffering high temperature load, the wide juncture concrete is bearing the stress from the slab track, which could easily causing tension and compression damage to the concrete around the tensioning lock.(3) When the interaction between the slab track and the concrete of wide juncture is strong enough, the "fake crack" of the slab track will craze under cooling load. But in fact, the interaction is weak, which can’t afford to keep the bonding, so it will craze first, which may impact the design concept of CRTS Ⅱ track slab.