In this paper, the influence of support type on mode II fracture experiments of asphalt concrete is investigated. The experiments were performed using three various types of supports i.e. roller, roller-in-groove and fixed supports, employed in semi-circular bend (SCB) testing fixture, under pure mode II fracture loading. These experiments were conducted at five different temperatures including −20, −10, 0, 10 and 20 °C. Based on the results, the fixed and roller types of supports exhibited the highest and lowest values of mode II fracture toughness and mode II fracture energy, respectively at all the test temperatures. While, the values of fracture toughness and fracture energy for the roller-in-groove type of supports were in between. Furthermore, friction coefficients at the contact regions between the supports and specimen were computed using the finite element analyses. A relation was finally proposed to calculate the value of mode II geometry factor for any value of the friction coefficient. Indeed, this relation can be used to calculate the mode II fracture toughness of asphalt concrete for various types of supports.

本文研究了支架类型对沥青混凝土II型断裂试验的影响。使用三种不同类型的支持物进行实验，即滚子、槽中滚子和固定支撑，用于半圆弯曲 (SCB) 测试夹具，在纯 II 型断裂载荷下。这些实验在五种不同的温度下进行，包括 -20、-10、0、10 和 20 °C。根据结果​​，在所有测试温度下，固定和滚子类型的支架分别表现出最高和最低的 II 型断裂韧性和 II 型断裂能。而滚轮槽型支撑的断裂韧性和断裂能值介于两者之间。此外，使用有限元分析计算了支架和试样之间接触区域的摩擦系数。最后提出了一种关系来计算任何摩擦系数值的模式 II 几何因子的值。的确，