Study On Generate Rules And Influence Of Interface Connection Damage Of The CRTSⅡ Slab Track

The slab track and concrete base layer of the CRTSII slab ballastless track are connected by mulsified asphalt cement mortar layer.Since the laying time of the CRTSII slab ballastless track is not long,there are a series of different levels of diseases appear during there service.interface damage phenomenon between slab track and mulsified asphalt cement mortar layer is appear many times during the field surveys,interface damage have a significant impact on life time and safety of slab ballastless track.at present the influence and generation mechanism of damage on interface connections are unclear.In this paper, the model of CRTSII slab ballastless track was built with finite element software –ABAQUS to study the produce and impact of interface damage.at first,establish a zero thick Ness cohesive element to simulation the bond between slab track and motor layer,analys the produce law of damage on interface under loads with different temperature gradients and different supporting la yer stiffness,analysis of the influence of stress and deformation characteristics of slab track and cement asphalt mortar layer structure by different temperature gradients and dynamic load under different damage conditions which include damage appears in slab ends、slab central and slab edge.The results show that the interface damage first appear in slab corner when the ballastless track under the load of temperature gradients, wirh the increase of the temperature gradients load,the area of interface damage zone gradually development to the slab edge. control factors of the emerge of interface damage is the shear strength between slab and mulsified asphalt cement mortar layer,and also,the more larger the stiffness of the concrete base,the more larger damage area occur at slab corner,so recommended increase the shear strength between slab and mulsified asphalt cement mortar layer and choose relatively small stiffness of the concrete base;when the track system which have interface damage are under the load of temperature gradients or dynamic load,the stress at the junction of interface damage region and normal region is the most unfavorable,this probably expand the area of interface damage,warping displacement of slab track increase greatly when the interface damage occurs;the displacement of slab track in interface damage region are greater than in the normal region when under dynamic load,at the same time aggravate the vibration of slab track,aggravate the damage of cement asphalt mortar.