北京地下直径线橡胶浮置板道床力学分析

对北京地下直径线隧道内连续式橡胶浮置板的力学特性进行研究,提出时速100 km国铁橡胶浮置板钢轨位移限值,进行浮置板道床的位移检算、结构配筋及锚固设计。根据连续式橡胶浮置板的传力特点,建立橡胶浮置板计算模型。考虑在列车荷载作用下道床板结构的弯矩、道床板所承受的由刹车和启动荷载引起的纵向力、因混凝土收缩及温度变化引起的道床板纵向力等。对连续式橡胶浮置板的力学特性进行计算分析,确定橡胶浮置板钢轨位移限值,检算轨道结构的竖向位移,并对浮置板道床进行了结构配筋及锚固设计。计算结果表明:(1)时速100 km国铁浮置板道床钢轨垂向变形限值可按4 mm取值;(2)本线采用的橡胶浮置板道床结构可以满足竖向位移限值的要求;(3)考虑垂向及纵向力的共同影响,连续式橡胶浮置板配筋量较大,配筋率约为1.28%;(4)为限制浮置板道床的纵向位移,需进行锚固连接,道床板锚固长度约为19 m。

Mechanics Analysis of Rubber Slab Track on Beijing Underground Diameter Line

The mechanical properties of continuous rubber slab track in the tunnel of Beijing underground diameter line are studied,and the rail displacement limit of rubber floating slab at the speed of 100 km / h national railway is put forward. The displacement of floating slab track is calculated and the structure reinforcement and anchorage are designed. According to the characteristics of force transmission of continuous rubber floating slab,the rubber floating slab calculation model is established. The following factors are taken into consideration: the bedding moment of the slab under train load; the longitudinal force of slab caused by the braking and starting load of trains; the slab longitudinal force caused by concrete shrinkage and temperature change. The rail displacement limit of rubber floating slab and vertical displacement of track structure are determined with calculation and analysis of force characteristics of continuous rubber floating slab. In addition,structure reinforcement and anchorage of floating slab track are designed. The results show that( 1) the vertical deformation limit of national railways floating slab track rail at 100 km / h can be set to 4 mm;( 2) the rubber floating slab track structure of this line can meet the requirements of the vertical displacement limit;( 3) in view of the combined effect of vertical and longitudinal forces,the reinforcement of continuous rubber floating slab is big quantity and the ratio of reinforcement is about 1. 28%;( 4) to limit the longitudinal displacement of floating slab track,anchor connection is required with about 19 m anchorage length,