Effects Of Concrete Aggregate On The Localization Of Damage

Currently, concrete is the most widely used engineering materials, Because of itswide range of raw materials and the economy, the construction industry to become thematerial of choice. However, the actual engineering often occurs due to concrete damagecaused by the collapse of the structure and, therefore, the failure mechanism of concreteis necessary.Structural failure occurs when the actual project size effect of concrete structures isoften a class of phenomena by the engineering attention. Literature and our engineeringpractice show, the evolution of structural damage to the damage occurred in the macroand micro view of a different order of spatial scales, so the size effect should be a verykey issue. Based on the same scale in different samples of concrete aggregate size of alarge number of experimental observations, the size of the concrete effects ofcatastrophic damage associated with aggregate size, and explores concrete aggregate sizeof the impact of catastrophic damage to the mechanism. At the same time, the use ofnumerical simulation to verify the test results, to further clarify its inner mechanism.Through the different aggregate size of the compression failure of concretespecimens for testing, and analysis techniques using speckle surface strain field by theirdistribution, the results showed that: the greater the aggregate size, specimen destroyedwithin a localized area the greater the average strain, and strain fluctuation is moreobvious, indicating the aggregate size of the sample compression failure when a largedegree of local small sample size than the aggregate violent, and prone to sudden disasterdamage. Through the different surface state of the concrete specimens for compressionfailure test results showed that: the cut surface when the sample in compression failurethan the natural surface of the specimen pouring more prone to sudden catastrophicdamage. Different samples of numerical simulation and experimental laws consistentwith the results, and study the aggregate skeleton specimens of concrete damageinfluence, to make up for the lack of test methods to further improve the researchprocess.