The Study Of The Rayleigh Wave Propagation Characteristics Of The Concrete Medium

Concrete structures are closely related to our life and property safety because they are widely used in our daily productions.Because of the influence of factors such as technology or man-made, there are some kinds of defects in concrete structures, in order to ensure our life and property safety, the nondestructive testing of concrete structure is particularly important.Rayleigh wave testing technique is an important method in the nondestructive testing of concrete structures of, because there are reinforcement in concrete structures, and other "abnormal body" strengthen the strength of concrete, the Rayleigh wave test, the "abnormal body" are often larger influence on test results, therefore, it is necessary to strengthen the Rayleigh wave propagation in concrete structures is studied.To study of Rayleigh wave propagation in concrete structures, establish a numerical model of concrete which is close to the actual is very important.This article uses the circular, elliptical, and irregular polygon to simulate aggregate in the two-dimensional plane shape characteristic, at the same time by different values of Pk to control aggregate area percentage in the model.Using the staggered-mesh finite difference technique to simulate the Rayleigh wave propagation in concrete structures in China. Wave field snapshot is obtained, the wave field record and a series of forward modeling results.And then, use the phase shift method and S transform, the dispersion curve, extracted from the wave field record of the aggregate, steel and other "abnormal body" of the impact of Rayleigh wave propagation.Six different model is established in this article, from Rayleigh wave in the transmitted wave field characteristics of these models, the different aggregate size, different size and different material steel parameters in the process of the propagation of Rayleigh wave impact.Then using the f-k separation technology isolate the base order waves from seismic wave, and using phase shift method and S transform method to calculate the dispersion curve.