Evaluation of concrete fracture procedure based on acoustic emission parameters

Acoustic emission (AE) acquiring technique was employed to explore the concrete fracture procedure in this study. Several parameters were evaluated through three-point bending beam tests using concrete fracture experiments. Acoustic emission instrument and strain gauges were used to monitor the initial and final fracture loads during crack propagation stage of specimens. In addition, the parameter values associated to crack propagations were obtained from the well-developed formula and test results. The typical trend curves and failure forms of each group of specimens were accompanied based on the crack-propagation theory. The designated concrete tests used in this study conducted a general process of crack fracture propagation. The experimental results indicated that AE detection system could well reflect the internal defects and cracks of the specimen. Additionally, the results illustrated that AE technology could reflect the initial fracture moment and final structure failure at a relatively low loading rate, and consequently could acquire the initial and failure fracture loadings. Based on this limited study, it can be found that, in most cases, concrete AE parameter characteristic could reflect the concrete crack propagation and its complete structure failure during the loading procedure. Additionally, it was found that the test results from AE method were similar to those from strain gauge method.