| The structure security has been the most important question which the people pay attention. But , the early warning of the disarrangement of the structure's effective is the most effective action to safeguard the people's safety and property .With the researching and applying of the acoustic emission in the field of concrete , the people began to realize that the acoustic emission has the incomparable superiority in the non-destructive inspection and the destruction early warning aspect. Acoustic emission also by its convenient, direct-viewing, real-time, dynamic, precise and so on many merits, substitutes for traditional gradually the examination method. In this article, the characteristic of acoustic emission of the reinforced concrete beams under load has been deeply researched. Also, the relevance of the Felicity effect and the load or the strain of the steel bar has been studied. Obtained the main research results were as follows:First, through in experiments of breaking the lead under the environmental condition ,We obtained several examination parameter of the acoustic emission conforms to the experimental material and the test condition, for instance, monitors the threshold, the time parameter (PDT, HDT, HLT), the wave velocity, the weaken and so on. This is the reliable safeguard for setting the parameter before the experiment Also it help us to obtain the best results of the experiment.Second, through the analytical study to the characteristic of the acoustic emission of the reinforced concrete beams, we obtained the co relational dependence of the AE parameters with the destroys of the beams. Thus we can forecast the limit supporting capacity of the reinforced concrete beams under the low load level. Third, in this article, the Kaiser effect has been studied according the experiment to reinforced concrete beams. Simultaneously, the Felicity effect has also been studied. Through the analysis and comparison to the parameters of acoustic emission, we established the method to find the Kaiser point, also we use this method to find the Kaiser point and found the relationship between the load and the Felicity ratio. We use this relationship to deduce the history of press to the reinforced concrete beams.Fourth, in virtue of the technology of 3D orientation, we discovered the location of the crack in the beam, and also find the trend of the crack when the beam was in loading. |
