Abnormal Response To Electrical Stimulation Roadway Excavation Hidden Warning System Design

In the tunnel driving, when there're old kilns,caves water-bearing structure in the front of the Tunnel Excavating Face, the supply current will be attracted by the hidden trouble. Moreover, with the tunnel boring, Tunnel Excavating Face is moving closer to potential, amplitude of the abnormal distributed electric field will continue to increase in a range. Through the magnitude and change trends in a range of the abnormal distributed electric field in the tunnel, can achieve warning and prediction of hidden troubles with different levels.In this article we discussed the electric field anomalies caused by low resistance faults watery hidden troubles, as driven by power of point. Theoretical calculations shows that the relative electric field anomalies increasing obviously, with closing to the hidden troubles, and the flume experiments has the same significant trend, which shows that electric field anomalies of low resistance faults watery structure presents a certain changes, as driven by power of point.Based on the feasibility of the methods and techniques of abnormal response to electrical stimulation, this article designs a set of equipment for excavation hazards'early warning system. This warning system is designed on the single chip W78E516B and put the high emission and signal acquisition together, through the simultaneous acquisition mode, making anomaly evaluation between the potential signal and regional background belonged to one part of tunnel. According to set the threshold control signal lights or sound alarm, this early warning system can be used by non-professional and technical personnel for geophysical prospecting.