考虑既有路面车辙状况的厂拌热再生沥青路面力学响应分析

Mechanical Response Analysis of Plant-Mixed Hot Recycling Asphalt Pavement Considering Rutting Condition of Existing Pavement

为研究既有沥青路面车辙状况下厂拌热再生路面的动态力学响应,本文通过现场获取不同车辙深度的路面芯样,并室内制备不同RAP掺量的厂拌热再生沥青混合料,通过动态模量试验评价材料的力学性能;利用3D-Move Analysis有限元软件分析不同结构组合的厂拌热再生沥青路面动力响应。结果表明:动态荷载作用下,再生路面各沥青面层均出现了拉压交互和应力集中的现象,再生路面结构随着车辙发展深度的加深出现拉裂破坏等病害的风险增加,但一定的车辙发展深度有助于提高沥青路面的承载能力。RAP掺量和既有路面车辙发展深度的改变将会使路面结构的模量组合发生变化,再生路面结构力学响应受这两种因素影响较大。为减少再生路面结构的永久变形并提高其耐久性,应充分考虑再生层和既有路面中面层的模量组合,从而改善再生路面结构受力情况。

In order to study the dynamic mechanical response of hot recycled asphalt pavement under rutting conditions,the author obtains the pavement core samples with different rutting depths in the field,prepares the plant-mixed hot recycling asphalt mixture with different RAP contents in the laboratory,and evaluates the mechanical properties of the material through the dynamic modulus test.The dynamic response of hot recycled asphalt pavement with different structure combinations is analyzed by 3D-Move Analysis finite element software.Under the dynamic loading,each asphalt surface layer of the regenerated pavement shows the phenomenon of tension-compression interaction and stress concentration,and the risk of the regenerated pavement structure developing such diseases as tensile cracking damage increases with the deepening of the rutting development depth,but a certain rutting development depth helps to improve the bearing capacity of the asphalt pavement.Changes in the RAP admixture and the depth of rut development of the existing pavement will cause changes in the modulus combination of the pavement structure,and the mechanical response of the recycled pavement structure is strongly influenced by two factors.To reduce the permanent deformation of the recycled pavement structure and improve its durability,the modulus combination of the recycled layer and the existing pavement medium surface layer should be fully considered,to improve the force situation of the recycled pavement structure.