摘要
现场调研表明,CRTSⅡ型板式无砟轨道宽窄接缝处存在严重破损情况,极大地影响轨道结构的受力和变形。为了明确宽窄接缝破损的影响,本文基于有限元理论,利用ANSYS软件建立了路基上CRTSⅡ型板式无砟轨道无缝线路计算模型,研究了温升和持续高温荷载作用下,宽、窄接缝分别破损对无缝线路受力和变形的影响。研究结果表明:在温度荷载作用下,与宽窄接缝完好时相比,宽窄接缝破损造成钢轨受力和变形增大,钢轨的垂向不平顺较为明显;宽窄接缝破损处两侧轨道板与砂浆层脱粘,轨道板出现上拱,并在持续高温作用下脱粘范围向板中蔓延,上拱位移不断增大。其中,宽接缝完全破损时脱粘长度可达到1.438 m,上拱位移达到0.612 mm,窄接缝完全破损时脱粘长度可达到1.625 m,上拱位移达到1.438 mm;宽窄接缝破损处的纵向压应力较大,超过混凝土抗压强度,导致混凝土被挤碎,破损程度加剧。
Field research demonstrated that there were some serious damages of wide and narrow joints in CRTS Ⅱslab-type ballastless track,which greatly influenced the stress and deformation of track structure.In order to ascertain the effect of the wide and narrow joint damage,a CWR（Continuous Welded Rail） computing model of CRTS Ⅱslab-type ballastless track on the subgrade was built by the finite element method theory and AN SYS software,and the effect of wide and narrow joint damage on the stress and deformation of CRTS Ⅱ slab-type track CWR under the condition of temperature rise and continuous high temperature was discussed respectively.The results show that the rail stress and deformation due to the wide and narrow joint damage increase and rail vertical irregularity is obvious under temperature load compared with the intact joints,the joint damage causes debonding between track slab and CA mortar and the arching of track slab,the debonding spreads to the center slab and the displacement of arching increases under continuous high temperature.Debonding length is 1.438 m and the displacement of arching is 0.612 mm when wide joint is completely damaged,while debonding length is 1.625 m and the displacement of arching is 1.438 mm when narrow joint is completely damaged,the longitudinal compressive stress at joint damage is large,the concrete will be crushed and the damage will be more serious when stress exceed the concrete compressive strength.
出处
《铁道建筑》
北大核心
2016年第5期58-63,共6页
Railway Engineering
基金
中国铁路总公司科技研究开发计划(2014G001-F
2012G008-A
Z2013-G001)
关键词
CRTSⅡ型板式轨道
宽窄接缝
破损
CRTS Ⅱ slab-type ballastless track
Wide and narrow joint
Damage
