| With the rapid development of transportation industry in China, the undergroundengineering and tunnel engineering has been going to a period of rapid development.Karst region and form kinds of castor physiognomy are widely distributed in China,karst area tunnel excavation process of underground engineering are often faced withlarger geological disasters, which are seriously impacting on the construction.To thisend, Adopting effective means of advanced prediction to find out the bad geologicaldisasters are effective methods to protect the safety of construction ahead of time.Based on the large railway tunnel as the research object, in previous studiesinformation collection and analysis of various detection methods on the basis of thebasic characteristics, after on the basic principle of geological radar and workingmethod were studied, then the combination of qualitative and quantitativeinterpretation of geological radar method applied to Xuda railway karst tunnelengineering,and using finite difference time method for different size, different shape,different filling, the karst caves in the detection range and typical dumbbelldevelopment of karst cave of Xuda railway conduct forward modeling research. Bysummarizing, the conclusions are as follows:（1）For the constraints of line ups and downs，which the influence of radareffective detecting depth was analyzed and put forwand the radar forecasting effectivedetecting depth formula.（2）Sum up the radar measured in the process of radar jamming factors of Xudarailway which suppression of radar jamming effective measures are put forwardcomprehensively and analyze the typical bad body by radar qualitative method, theanalysis results help radar to interpret the bad geological body.（3）For the wet、the liner、the planar flow、shares of running water ofconstrains、empty cave、hybrid cave and so on, conducting spectrum analysis,concluding the main frequency and peak value difference characteristic differencesbetween them, which put forward another method of interpreting bad geological bodyand help radar to interpret the bad geological body quantitatively. （4）For referring to interface of the geological body of Xuda railway,which canconduct file interactive interpretation by radar that calculate the propagation velocityof electromagnetic wave in the formation and calculate the relative dielectric constantof the medium, which provide adequate basis that radar interpret such special badgeological body and help radar to interpret the bad geological body quantitatively.（5）For the different size、the different shape、different filling、differentdetection range of cave proceed radar forward modeling, summing up the waveformcharacteristics of the differences between them; For typical dumbbell development ofthe cave of Xuda railway conduct forward modeling analysis, the simulation resultswhich are used in dumbbell development project of Xuda railway acquire bettereffect. |
PDF Full Text Request