TY - GEN
T1 - Observation of crack propagation in asphalt mixtures with acoustic emission
AU - Li, Xue
AU - Marasteanu, Mihai O.
AU - Iverson, Nathan
AU - Labuz, Joseph F.
PY - 2006
Y1 - 2006
N2 - Fracture in quasi-brittle materials is associated with the formation of microcracks, which release energy in the form of elastic waves called acoustic emissions. The use of acoustic emission (AE) in the characterization of the fracture behavior of asphalt mixtures at low temperatures is investigated, and a method that uses AE to locate the crack path is presented. An application of the method is detailed for fracture tests performed with the semicircular bend specimen on asphalt mixtures at low temperatures. A network of seven piezoelectric sensors was used to capture AE signals, and a nonlinear regression algorithm was employed to locate the AE events. The locations of microcracks were in good agreement with the crack path observed at the end of the test When the load increased beyond 70% of the peak load, the rate of AE activity was significant, indicating the formation of microcracks, and the location of AE was concentrated in a distinct area called the process zone. Moreover, the location of AE in the postpeak load showed the movement of the process zone and identified the crack propagation in the macroscale.
AB - Fracture in quasi-brittle materials is associated with the formation of microcracks, which release energy in the form of elastic waves called acoustic emissions. The use of acoustic emission (AE) in the characterization of the fracture behavior of asphalt mixtures at low temperatures is investigated, and a method that uses AE to locate the crack path is presented. An application of the method is detailed for fracture tests performed with the semicircular bend specimen on asphalt mixtures at low temperatures. A network of seven piezoelectric sensors was used to capture AE signals, and a nonlinear regression algorithm was employed to locate the AE events. The locations of microcracks were in good agreement with the crack path observed at the end of the test When the load increased beyond 70% of the peak load, the rate of AE activity was significant, indicating the formation of microcracks, and the location of AE was concentrated in a distinct area called the process zone. Moreover, the location of AE in the postpeak load showed the movement of the process zone and identified the crack propagation in the macroscale.
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U2 - 10.3141/1970-20
DO - 10.3141/1970-20
M3 - Conference contribution
AN - SCOPUS:33847146666
SN - 030909979X
SN - 9780309099790
SP - 171
EP - 177
BT - Bituminous Paving Mixtures
PB - National Research Council
ER -