钢桥桥面铺装层间剪应力影响因素及简化计算

Influence factors and simplified calculation of interbedded shear stress of asphalt paving on steel bridge

为了减小钢桥桥面铺装层间剪应力,建立桥面系三维有限元计算模型,分析了不同荷位、钢板厚度、U肋开口宽度、铺装厚度、铺装模量、层间接触条件以及轴载大小对铺装层间纵横向剪应力的影响,推导了实用的应力简化计算公式。研究发现桥面板不均匀变形使得铺装层间剪应力远大于同条件下的路面结构;影响显著的因素依次为轴载大小、钢板厚度、U肋开口宽度以及铺装参数;层间完全光滑有利于抗剪,但降低了桥面系整体刚度;控制重载,加强桥面系刚度与选择柔性层间粘结材料是减小层间剪应力的有效措施。

In order to minish the interbedded shear stress of asphalt paving, 3-D finite element model of bridge deck was set up, the influences of load position, steel deck thickness, the open width of U shape rib, asphalt thickness, asphalt modulus, contact condition and heavy load on the longitudinal-transverse shear stresses were analyzed, and the simplified calculation formulae of the stresses were concluded. It is pointed that the shear stresses are much larger than that of road structure in same condition because of uneven deformation, the main influence factors in order are heavy load, steel deck thickness, the open width of U shape rib and paving parameters; completely smooth state between asphalt concrete and steel deck lowers the whole stiffness of deck system, but benefits to resist shear stress; controlling heavy loads, stiffening steel deck and selecting flexible interbedded sticking materials are effective method to reduce the shear stress between steel deck and asphalt paving.