Acoustic Emission Region Localization Of Damage Evolution Of Concrete

Concrete serves as one of the most important and widely-used building materials andits damage fraction process has always been the research hotpot and difficulty in variousdisciplines, such as mechanics, civil engineering and materials. The damage evolution ofconcrete is a complicated nonlinear evolution process and the damage process manifeststhe emergence of microcrack, its development and final instability and construction.Acoustic emission technique is a dynamic nondestructive testing technique that developsin recent years and its advantages of easy operation, high sensitivity, visual effects andreal-time monitoring are widely applied to many fields, such as performance evaluationand damage testing. The paper aims to apply acoustic emission technique to test the crackpropagation and failure mode, and also carries out research and analysis on the process ofdamage evolution.The paper investigates the acoustic emission performance of concrete material andbuilds up relationship between the change of concrete’s inner damage and that of acousticemission signals parameters. It also carries out uniaxial compression test loading acousticemission system and compares the damage process and form of different aggregate sizesand those of the concrete samples of surface states under the condition of uniaxialcompression. The paper also analyzes the corresponding relations between acousticemission signal parameter and overall damage process, and studies acoustic emissioncharacteristics of different samples, exposing the damage evolution process of concretefrom microscopic view.The paper carries out fatigue loading experiment and classifies fatigue damage stagesof concrete based on the observation of test phenomenon and acoustic emission testingresults. It also analyzes and processes all acoustic emission signal parameters derivingfrom the test, thus concluding acoustic emission characteristics and regulation of damageevolution of different aggregate sizes and concrete samples of surface state in variousstages. According to the damage levels of concrete material, the paper carries out partitiondescription on concrete, defines the safety zone, damaging zone and broken zone of concrete material, discusses the threshold standards of partition acoustic emissionparameters and finally researches the creation condition of concrete material’s damagingzone in such standard.