动载作用下沥青路面内部孔隙水压力的轴对称弹性解

将沥青路面视为多层饱和弹性半空间轴对称体,引入比奥渗流固结理论和渗流方程.利用Hankel和Laplace积分变换等数学方法,推导出浸水沥青路面的沥青路面水损害力学模型,并做出如下假设:除渗透性外,沥青混凝土是均质的、完全饱和的理想弹性材料;沥青混凝土的变形是微小的;沥青混凝土和孔隙水均不可压缩;孔隙水渗流服从达西定律,渗透系数为常数.计算了沥青路面结构层孔隙水压力大小.结果表明,沥青面层内的孔隙水压力与面层渗透系数、面层厚度、结构层材料参数以及车辆行驶速度等有密切关系.当路表孔隙饱水时,在荷载作用下,面层中以及面层与基层的接触面附近孔隙水压力最大,在荷载的反复作用之下,导致疲劳开裂破坏,加速路表病害的出现.

Axial symmetric elastic solution of pore water pressure in asphalt pavement under mobile load

Regarding asphalt pavement as an axial symmetrical body of multilayered saturation elastic half space,the fundamental thermal Biot consolidation theory and seepage flow equations are introduced.By using mathematical method the mechanical model of water damage of the asphalt pavement is derived.And the following assumptions are made: except for penetrability,the asphalt concrete is a kind of ideal stretch material being homogeneous and entirely saturated;the distortion of asphalt concrete is tiny;the asphalt concrete and the pore water can not be compressed;the pore water seepage flow submits to the law of Daxi,and the penetrating quotiety is constant.The pore water pressure in asphalt pavement is calculated based on some mathematic methods such as Hankel and Laplace integral transformations.Calculation results indicate that the pore water pressure in the inner asphalt pavement has close relation to permeation coefficient of surface,thickness of surface,material parameter and wheel speed etc.Pore fluid stress at the interface between surface layer and base layer of the flexible pavement is maximum when the pore of pavement is full of water,under the action of load.Under the iterative action of load,the pavement fatigue cracking may occur,which accelerates the appearing of breakage of pavement.