摘要
为研究轨道板与砂浆层层间离缝产生的原因,推导了轨道板在砂浆层或砂浆层和张拉钢筋约束下的解析解,分析了层间离缝产生时轨道板的临界伸缩温度T L。结果表明:轨道板伸缩刚度极大,砂浆层较难约束轨道板的伸缩变形,离缝产生时的T L主要与砂浆层对轨道板约束达到最大时的临界位移有关;虽然中国现场测试所得的轨道板与砂浆层层间摩阻力系数k c明显大于德国,但推板力达到最大时的临界位移为0.01~0.06 mm,远小于德国推板测试的0.5~0.9 mm,导致离缝产生时的T L远小于德国;张拉钢筋纵连后,离缝产生时的T L增加,中国T L增加0.1~0.5℃,德国T L增加4.1~7.3℃;为降低离缝产生的概率,CRTSⅡ型板式无砟轨道在设计和加固维修时,建议针对砂浆层对轨道板的变形适应性提出要求。
In order to study the causes of the gap between the track slab and the mortar layer,the analytical solutions of track slab expansion under the constraint of mortar layer or under the constraints of mortar layer and tensioned rebars were derived.The critical expansion temperature of track slab T L when the gap under the track slab was generated was analyzed.The results show that With large stiffness of the track slab expansion,the deformation of track slab expansion can be hardly constrained by mortar layer.When the gap under the track slab is generated,T L is mainly related to the relative displacement between the track slab and the mortar layer when the constraint on the track slab caused by the mortar layer reaches the maximum.Although the frictional resistance coefficient k c between the track slab and the mortar layer obtained from China’s field test is obviously larger than that of Germany.When the pushing plate force reaches maximum,the critical displacement from the pushing plate test in China is 0.01-0.06 mm,which is far less than the 0.5-0.9 mm measured by the German pushing plate test.As a result,when the gap under the track slab is generated,T L from China is much less than that from Germany.When the connection of tensioned rebars is finished,T L from China increases about 0.1-0.5℃,while T L from Germany increases about 4.1-7.3℃.To reduce the probability of gap,requirements should be put forward for the adaptability of the mortar layer to the deformation of the track slab in the design process and reinforcement maintenance of CRTSⅡslab ballastless track.
作者
朱永见
赵国堂
郑建
ZHU Yongjian;ZHAO Guotang;ZHENG Jian(MOE Key Laboratory of High-speed Railway Engineering,Southwest Jiaotong University,Chengdu 610031,China;China State Railway Group Co.,Ltd.,Beijing 100844,China;North of Jiangsu Railway Co.,Ltd.,Xuzhou 221000,China;Sohool of Civil Engineering and Architecture,Taizhou University,Taizhou 318000,China)
出处
《铁道学报》
EI
CAS
CSCD
北大核心
2021年第2期111-117,共7页
Journal of the China Railway Society
