Evaluation of Tunnel Seismic Prediction (TSP) Test Results based on Geological Observations and Analysis of the Parameters of the EPB Hard Rock Machine

Bazideraz's water transfer tunnel is located in the Zagros structural zone. To excavation this tunnel, an EPB Hard Rock type TBM machine was used. The axis of the tunnel is located on an Anticline. In this anticline, there are various geological structures such as folding, fault, karst, and so on. The underlying studies of the design and implementation of exploratory specimens in the core of this anticline have been confined. In this research, for study of geological conditions during drilling, seismic prediction of tunnel (TSP) test was carried out at two positions of 287 + 3 and 577 + 5. In this geophysical method, seismic waves are used to illustrate geological structures. The distribution of shear waves in a three-dimensional tunnel model provides evidence of lithological changes (alternation of marl and shale and limestone layers) and the existence of several crushed zones along the drilling path. Bazideraz Tunnel is the first project in the world to use the TSP method to drill a EPB machine. In this study, the analysis of the operational parameters of the EPB machine and Observe rock mass during drilling was used to measure the accuracy of the TSP results. The fluctuations of the penetration rate, thrust and torque in the drilling path are in accordance with the low velocity and high velocity regions of the three-dimensional shear waves. Results of controlling the drilling materials indicate that the shear waves distribution models have a relative adaptation to the geological conditions in the drilling path.