旧沥青路面对超薄水泥混凝土路面荷载应力影响

Effects of existing asphalt pavement on loading stress of ultra-thin-whitetopping pavement

为了定量分析旧沥青路面对 UTW路面使用性能的影响程度 ,将 UTW路面板视作面层 ,沥青层视为基层 ,旧沥青路面基层以下部分视为综合地基 ,利用弹性三层体系模型 ,应用三维等参元法 ,计算分析了旧沥青路面铣刨后剩余厚度、弹性模量与路面板厚度、地基综合模量对超薄水泥混凝土路面荷载应力的影响。研究表明 ,板底弯拉应力随沥青层厚度呈线性变化 ,且斜率与 Es有关 ;路面板较薄时 ,控制沥青层厚度大于 6 cm,有利于 UTW路面的使用 ;对于一定的路面板厚度 ,当沥青层弹性模量大于某一值后 ,对路面板底弯拉应力影响很小 ,可以此值来评价旧沥青层品质 ;随着 Ea 的减小 。

Ultra-thin-whitetopping(UTW) is a recently developed rehabilitation technique of distressed asphalt concrete pavement. For quantitatively analyzing the influence degree of the existing asphalt pavement to UTW pavement, UTW slab is regarded as surface layer, the existing asphalt layer is regarded as base course, and the layers under the base of existing asphalt pavement are regarded as the compositive ground. Using the three-dimensional isoparametric element, according to elastic three-layer model, loading stresses of UTW are calculated. On the basis of these results, the effects of asphalt thickness, thickness of slab, and general modules of ground(E c) on the stress are analyzed. The results indicate that loading stress of slab bottom varies linearly with thickness of asphalt, and the slope is relate to the modules of the ground(E s). The thickness of asphalt exceed 6cm was favorable for serving of UTW while the slab was thin. Elastic modules of asphalt layer exceeding certain value little influenced to stress of slab bottom of pavement, and this value can be utilized to evaluate quality of existing asphalt layer.With decreasing of the elastic modules of asphalt,thickness of asphalt layer bring minus effect to the stress of slab bottom.1 tab,10 figs,8 refs.