设沥青夹层水泥混凝土路面早龄期力学行为与作用效应研究

基于水泥混凝土路面早龄期三维有限元力学分析程序，对设沥青夹层面板结构早龄期阶段力学行为和性状形成的结构效应、沥青夹层效应进行了研究。研究发现，早龄期阶段固化温度、混凝土的徐变和硬化历程与环境场叠加作用，会引起面板更大的早期板角翘曲和脱粘，以往传统分析理论忽略了此方面影响。设沥青夹层结构比无夹层直接加铺路面脱粘面积小、翘曲变形更大。沥青夹层面板早龄期增大翘曲、脱粘的结构效应与特定重载交通共同作用下可能产生对路面板疲劳寿命不利的影响。对设沥青夹层加铺结构建议采用刚度较大的基层，夹层厚度宜在30 mm以内，沥青夹层混合料模量宜选低值。

EARLY-AGE MECHANICAL BEHAVIOR AND ACTION EFFECT OF CEMENT CONCRETE PAVEMENT WITH ASPHALT INTERLAYERS

By using three-dimensional finite element analysis, structural behavior of early-age Portland cement concrete pavement (PCCP) with asphalt interlayers was studied. The effects of the asphalt interlayers on the formation process as well as the early-age behavior of PCCP were analyzed with respect to its mechanical properties. The analysis results show that the combined action of built-in temperature in early age, concrete's creep, hardening process and the environment fields cause more significant early-age curling and interfacial debonding at the slab corners. Such effects were however neglected by traditional theories. PCCP with asphalt interlayers has smaller debonding areas and larger curling deformation compared with the directly-overlaid pavement without asphalt interlayers. In addition, combining with specific heavy traffic, structure effect of the early-age curling and debonding may have an unfavorable influence upon fatigue life of pavement structures with asphalt interlayers. On the basis, it is suggested to use bases with larger stiffness in PCCP with asphalt interlayers. In particular, the thickness of the asphalt interlayers should be less than 30 mm, and the elastic modulus of asphalt mixture should be of low values.