Parameters Analysis Based On Ansys In The Underground Caves Survy By Transient Rayleigh Wave Method

The engineering sites of the construction project will be across inevitably underground caves of which physical and mechanical properties are different from the surrounding media, such as karst cave, mined-out area, culvert pipe, soil cave and so on. These underground caves of the construction engineering will cause serious geological diseases, so there will be great significance to the engineering quality and safety to detect the burial condition of these caves. Transient Rayleigh wave exploration method is suitable for detection the underground caves in the large geotechnical engineering field, which is economical and effective.The test device parameters and strata structure impact seriously on survey results, when underground caves are detected by Transient Rayleigh wave exploration method, so the parameters analysis is particularly important. The site investigation to analyze parameters influence is heavy work and no uneconomical, therefore, the finite element simulation method can be considered and will be effective. The realization of ANSYS numerical simulation of detection underground caves by transient Rayleigh wave method is discussed in this thesis, and the result show that the numerical simulation method instead of the site survey is feasible.In this thesis, based on the basic principle, data processing and data analysis of the transient Rayleigh wave method, series of stratigraphic model containing underground caves are built. All kinds of parameters are analyzed statistically when underground caves are detected by Transient Rayleigh wave exploration method, and some engineering proposals is gotten to guide the site survey. Result shows:the offset distance is the biggest influence factors, and the position of the underground caves can be determined by changing the geophone arrays. The stratum structure is also has a certain effect on the detection result, and thickness of strata is the important influence factors.Finally, the engineering site is selected, where the condition of engineering geology, buried deep and diameter of underground caves are known. The selected engineering site is detected by transient Rayleigh wave method. Through analyzing detection data, engineering proposals proposed in this thesis are verified correct.