Investigating Simple Brittleness and Cracking Indexes for Cold In-Place Recycling

摘要

In recent years, cold in-place recycling (CIR) researchers have been looking more and more to dense graded asphalt (DGA) testing principles, particularly in relation to cracking. More advanced tests like the disk-shaped compact tension (DCT) require modest-to-intensive specimen sawing procedures and instrumentation, which can present challenges for more friable materials like CIR. Simpler DGA cracking tests [e.g. IDEAL cracking test, indirect tensile (IDT) N_(fiex) factor] have become a recent focus, and these types of simpler tests should be investigated for CIR. If specimen preparation and testing complexities can be alleviated, simplified tests may have value for CIR. This paper's objective is to investigate simple CIR brittleness and cracking index parameters that can be obtained from non-instrumented IDT testing. Multiple CIR blends encompassing a range of cracking behaviors were tested, and results indicated cracking properties could be sufficiently characterized by energy index (EI), a simplified fracture energy term, and IDT strength.