超载条件下混合式基层沥青路面层底拉应力研究

Tensile Stress at Bottom of Composite-Base Asphalt Pavement Layers in Condition of Overload

分析半刚性基层的缺点,提出混合式基层沥青路面结构,并给出超载条件下轴载计算参数。采用Bisar3.0软件,计算在完全连续、部分连续和完全光滑三种界面条件下混合式基层沥青路面各结构层层底拉应力。结果表明,在完全连续条件下沥青层不会产生拉应力,路面内部拉应力最大值出现在半刚性基层底部;当沥青层与半刚性基层之间的接触条件由完全连续向完全光滑转变时,沥青层层底和半刚性基层层底的拉应力逐渐增大;在三种界面条件下,沥青面层表面轮隙中心处都出现较大的拉应力。

The paper analyzes the defects of the semi-rigid base, proposes asphalt pavement structure with the composite base and the axle parameters in overload condition. Using Bisar3.0, the paper calculates the tensile stress at the bottom of each layer of composite-base asphalt pavement in the condition of completely continuous, partially continuous and perfectly smooth interface. The result shows that： in completely continuous condition, there won＇t be any tensile stress at asphalt layer, and the maximum value of pavement＇s internal tensile stress ap- pears at the bottom of semi-rigid base; when the contact condition between asphalt layer and semi-rigid base transforms from completely continuous condition into perfectly smooth condition, the tensile stress at the bottom of asphalt layer and semi-rigid base increases gradually; in the three conditions of interface, there are comparatively great tensile stress appear at wheel gap centers on asphalt surface.