Fracture process and reliability of concrete made from high grade recycled aggregate using acoustic emission technique under compression

The increasing amount of waste concrete makes desirable collection of high quality of recycled aggregate from waste concrete to be reused for construction. This research used high grade recycled coarse aggregate (RCA) created using pulsed power technology to make concrete specimens. Concrete created from natural aggregate was also prepared to compare the properties of concrete made using pulsed power recycled aggregate. Established acoustic emission (AE) parameter analyses which are AE hit, relationship between RA value and average frequency, and b-value of AE amplitude distribution were applied to analyze the concrete fracture behavior. In addition, AE Weibull analysis was also proposed to evaluate the reliability of the concrete. A set of AE measurement testing was applied to the concrete specimens during compression loading. At the age of 28 days, compressive strength reaches 35.4 MPa and Young's modulus is 23.6 GPa. The results indicate that the fracture process and reliability of concrete made using pulsed power RCA is similar to that of natural coarse aggregate concrete suggesting that both concrete have equivalent characteristic under compression. Furthermore, the good agreement results shared by AE Weibull analysis with those of other analyses suggesting this method can also be employed as one parameter to determine the condition of concrete.