RCC-AC路面温度荷载型断裂的有限元分析

在沥青水泥混凝土AC层中接缝的上方存在一条垂直路面结构的反射裂缝的条件下，研究温度变化对反射裂缝的影响，并考虑沥青水泥混凝土AC层与碾压水泥混凝土RCC板之间的接触，摒弃两层之间完全连续的假设。其步骤为：利用传热学原理，得出路面结构的温度场，再利用热弹性理论求出不同温度条件下产生的热应力；然后，利用断裂力学理论计算复合式路面裂缝尖端的应力强度因子。此外，根据工程实例得出了不同裂缝长度下的应力强度因子，并分析了不同因素对应力强度因子的影响。研究结果表明：降低AC层与RCC板之问的粘结程度，加铺低模量的土工布，适当提高AC层的厚度等方法，能降低裂缝尖端的应力强度因子，从而达到阻碍反射裂缝开裂扩展的作用。

Finite Element Analysis of Temperature Fracture in RCC-AC Composite Pavement

On the condition that a reflecting crack existing in AC layer is perpendicular to the pavement and above the jointed crack, the impact of changes of temperature on the crack is studied, and the contact between AC and RCC layers is considered, which gives up the hypothesis that these two layers are complete continuance. The distribution of temperature field of composite pavement is obtained using heat transfer theory, then the thermal stress caused is obtained using thermal elastic theory. At last, the stress intensity factor(SIF) of crack tip in the composite pavement is obtained using fracture mechanics theory. SIFs of different length cracks are obtained in a real engineering instance, and the impacts of different factors on SIF are considered. The results show that abasing the interlayer bond between AC layer and RCC plate, and adding low module geo-textile between them, adding the thickness of AC layer properly and so on, the SIF of crack tip will be decreased, which can prevent the initiation and expanding of reflecting crack effectively.