砼-岩一体两介质破裂过程中声发射特征试验

Test of Acoustic Emission Characteristics during the Rupture of Bi-material in Concrete-rock

研究砼-岩一体两介质在受载条件下的声发射特征,可为预测该类型材料的破裂失稳提供科学依据。为此开展了砼、岩石、砼-岩一体两介质在单轴压缩条件下的声发射特征研究。结果表明:砼-岩一体两介质的能量计数曲线在破裂演化过程中呈现双峰值,峰值1的声发射特征可作为岩石材料失稳的预判;声发射事件的时空演化规律表明砼-岩一体两介质的非稳定破裂发展先从砼材料开始,而后通过砼-岩胶结面诱导岩石材料发生失稳破坏;声发射空间定位聚类结果表明砼材料先发生剪切失稳,而后通过失稳过程中所释放出的断裂动能以及骨料的应力集中,诱导岩石材料发生劈裂破坏。

The study on acoustic emission characteristics of the bi-material made of concrete and rock under loading condition can provide a scientific basis for predicting rupture instability of this material.Thus,some relevant experiment works on concrete,rock and bi-material were carried out which were for probing into acoustic emission characteristics.Through the experiments,the following results are obtained.For bi-material,double peaks are clearly presented in the energy count curve during rupture evolution process,and the first peak can be used for predicting its instability.The spatial-temporal evolution law of acoustic emission events indicate that unsteady rupture development of the bi-material firstly begins with the concrete,then the rock material is into unstable state via cementation surface.The clustering results of acoustic emission location indicate that shearing instability firstly occurs in the concrete,then the kinetic energy released by fracture instability and stress concentration of the aggregate induce the fracture of rock material.