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Cracking in asphalt pavement is a common form of distress, often caused by low-temperature stress and fatigue loading. Fracture mechanics suggests that micro-cracks or defects within the material concentrate stress at the crack tip, leading to crack propagation. Studying crack resistance using fracture mechanics methods can be highly effective. In laboratory testing, artificial notches are introduced in asphalt specimens to simulate real-world cracking conditions, facilitating accurate evaluation of pavement durability.

The AASHTO and ASTM standards have incorporated several test methods for evaluating pavement material performance, including:

• AASHTO T393 (TP124) – Semi-Circular Bend (SCB) Test at ambient temperature.

• AASHTO T394 (TP105) – Semi-Circular Bend (SCB) Test at low temperatures.

• ASTM D7313 – Disk-Shaped Compact Tension (DCT) Test for evaluating fracture resistance.

• Other experimental methods – Research-based tests not yet standardized, such as notched beam three-point/four-point bending tests.

A specialized cutting machine was developed to meet precise notching requirements for asphalt pavement testing, as standard lab saws struggle to achieve the necessary 1.5mm width and 10mm depth. This machine features a fixed-position precision saw blade, a variable-speed motor, and manual linear motion control to ensure ±0.1mm width accuracy, enabling reliable fracture mechanics evaluations in pavement research.