Mode II fracture tests on asphalt concrete at different temperatures using semi-circular bend specimen loaded by various types of supports

• Published in: Theoretical and applied fracture mechanics Vol. 116; p. 103089
• Main Authors: Pirmohammad, S., Abdi, M., Ayatollahi, M.R.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01.12.2021; Elsevier BV
• Subjects: Asphalt; Asphalt concrete; Coefficient of friction; Experiments; Finite element method; Fracture testing; Fracture toughness; Fracture toughness and energy; Friction; Grooves; Loading supports; Mathematical analysis; Mode II fracture loading; SCB specimen; SCB specimen; Fracture toughness and energy; Loading supports; Asphalt concrete; Friction; Mode II fracture loading
• ISSN: 0167-8442; 1872-7638
• DOI: 10.1016/j.tafmec.2021.103089

•Roller, roller-in-groove and fixed supports are used to perform fracture tests.•Experiments are conducted at five different low and intermediate temperatures.•Fixed supports exhibited the highest mode II fracture parameters.•Friction coefficients at the contacts between the supports and specimen are computed.•A relation is given to calculate the mode II fracture toughness of asphalt concrete. 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.