The Research On Tunnel Seismic Prediction Of TBM Tunnel

With the rapid development of the national economy,in order to ensure the sustainable development of the economy,China has carried out a large number of basic traffic construction projects.There are a lot of mountains in China,as a special underground building structure,The tunnel has received more and more attention.During the excavation of the tunnel,the uncertainty of the rock mass in front of the tunnel(such as faults,weak structural planes and other poor geographical bodies)have a great influence on the schedule,safety and economy of engineering.In order to reduce the risk of excavation and reduce the damage caused by poor geographical bodies to personnel and equipment,it is of great significance and practical value to adopt advanced geological forecasting technology in tunnel construction.Tunnel seismic prediction is the mainstream of tunnel advanced geological prediction,based on the elastic difference of the surrounding rock,the method is used to detect the structure of the geological body in front of the tunnel surface by using the principle of seismic exploration.It has the characteristics of wide detection range,high resolution and little influence on the project.However,the conventional method stimulates the source on the tunnel wall and receives the signals on the tunnel wall.It used the way to detect the geological structure in front of the tunnel face,with the disadvantages of low spatial resolution and large influence by the tunnel engineering.at the same time,the wave filed is complicated and contain a little information about the reflective surface in front of the tunnel surface as the seismic wave propagates in the three dimensional space,so that the interpretation has low accuracy and non-unique problem.In order to overcome those problems,we conducted a research about the tunnel seismic prediction in this paper.First of all,we have analyzed the advantages and disadvantages of the existing methods from the perspective of wave filed by the studied about the numerical simulation of the tunnel wave field.Then,we put forward the new three-dimensional date acquisition method that disposal with system of observation on the tunnel face,and we also analyzed the feasibility,limitation,and data processing methods of the method for detecting the geologic body in front of the tunnel face from the aspects of the arrangement of the observation system,the wave filed characteristics and the processing mode of the forward date.On this basis,this method is used to carry out the actual data acquisition and processing experimental research,analyze the characteristics of the actual date,including the form of effective information,the type of the noise,etc.combined with forward data processing methods to deal with those problems,and ultimately perfect the method,improve the prediction accuracy of the spatial position and morphological structure of the geological space in front of the tunnel face.