It is an important subject to probe the structure in the medium by various kinds of detection methods
in the geotechnical engineering. Based on the propagation theory of elastic wave in half-space layered medium,
the propagation characteristics of elastic wave in layered medium with different elastic parameters are discussed
using dynamic analysis of finite element method. It is known that the S-wave velocity, density and thickness of
layer are related to the properties of the elastic wave including waveform characteristics, spectral characteristics
and time-frequency characteristics. We pay special attention to the structure with low velocity interlayer. The
impact imaging method is applied to the grouting construction of the immersed tube tunnel. Data acquisition
and analytical method are introduced in detail. The grouting effects can be qualitatively evaluated by comparing
the characteristics of elastic wave before grouting with those after grouting. Finally, a quantitative evaluation is
obtained according to the relationship between energy response of elastic wave and impedance ratio.
LIU Chao (刘 超), CHE Ai-lan* (车爱兰), FENG Shao-kong (冯少孔)
. Propagation Characteristics of Elastic Wave in Layered Medium and Applications of Impact Imaging Method[J]. Journal of Shanghai Jiaotong University(Science), 2013
, 18(4)
: 479
-485
.
DOI: 10.1007/s12204-013-1424-z
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