Research Of Acoustic Emission Technique In Healthy Monitoring Of Concrete Structure

Because of the long-term action of load or abrupt disaster under the term of usage, the concrete structure will appear the safety problem and endanger the property and the security of people's life. Healthy monitoring of structure must be carried on for avoiding these accidents occurring. In civil engineering field, Nondestructive testing can evaluate and ensure the safety of the structure.Acoustic emission technique had an extensive application in the healthy monitor aspect as a kind of dynamic of nondestructive testing. But because of the concrete is a inhomogeneity, large amount of porosities and anisotropy complex mixing, it has not only complicated constructions, but also great disperse of character, AE, which was very effective to mechanical industry, was incapacity for work in civil engineering field. It must take some advancement on technique and skill for application.This text studied the application of acoustic emission technique in healthy monitoring of concrete structure. The research involve monitor the destroy of reinforced construction and fatigue crack of CFRC. By experiment research, we brought forward the proper project, eliminated influence of monitoring condition, carried reasonable of parameter analysis on result, gained internal information of material and provided related basis for actual monitor. By the experiment of monitoring the fracture process and mode of the ferrocement/steel bar-mesh strengthening columns under axial loading by AE, we find that, the failure capability of columns were controlled by part area, which the acoustic emission characteristics reflect the failure process of columns. Good correlation was observed between AE signals and failure mode of protecting the mortar cover. We also studied the rupture and fatigue of the CFRC by AE. The results indicated that the short carbon fiber arrest crack during the period of critical expand in concrete. By using the trigger sensor, we can monitor the signal from the area that had appointed, thereby tracing the expanding of fatigue crack.In addition, we studied the method that evaluated technology of preparing for...