Microseismic-monitoring-sensor arrangement method for stratified excavation of deeply-buried hard-rock tunnel

Abstract

The invention discloses a microseismic-monitoring-sensor arrangement method for stratified excavation of a deeply-buried hard-rock tunnel. When a second layer to the last layer of the tunnel are excavated, a first group / second group of microseismic sensors are installed in rock mass of a tunnel inner wall at the front / back of a tunnel face; a line obtained through downward movement of a center line of a currently-excavated-layer bottom plate for 1 meter is used as a rotating center line and the first group of microseismics sensors and the second group of microseismic sensors are distributed in the rock mass of the tunnel inner wall, the rotating center line being a central axis; and with the advancement of the tunnel face, the first group of microseismic sensors and the second groups of microseismic sensors are redistributed until tunnel excavation is completed. In the method, through use of space supplied by excavated layers of a tunnel, microseismic sensors are arranged at the front and back of excavated tunnel faces and a tunnel face of higher risks and adjacent areas of the tunnel face are included in the two groups of microseismic sensor arrayed at the front and back of the tunnel face all the time so that acquisition of micro-fracture signals is facilitated, microseism positioning precision is ensured and a basis is laid for accurate prediction and forecast of a disaster.

Description

technical field [0001] The invention relates to tunnel microseismic monitoring technology, and more particularly relates to a method for arranging microseismic monitoring sensors for layered excavation and deep buried hard rock tunnels, which is suitable for layered excavation tunnels for water conservancy, hydropower, transportation, etc. Background technique [0002] Layered excavation is often adopted for tunnels due to the large section size during full-section excavation, which makes it impossible to construct or has high risks. Layered excavation refers to dividing the tunnel into multiple layers from top to bottom, and gradually excavating layer by layer. During the excavation of deep-buried hard rock tunnels with layered excavation, strong stress adjustments will occur near the face of the tunnel. When excavated by the drill-and-blast method, severe blasting disturbances will be encountered, resulting in easy Catastrophic accidents such as rock bursts, landslides or...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to address the above-mentioned defects in the prior art, to provide a method for arranging microseismic monitoring sensors for layered excavation and deep buried hard rock tunnels, so as to solve the problem that it is difficult for the microseismic monitoring sensor array to displace the face and its vicinity during tunnel excavation. The problem of being surrounded by rock mass enables more effective micro-crack source signals to be captured by micro-seismic sensors on the face of tunnel excavation and its vicinity, improving the positioning accuracy of micro-seismic sources and laying the foundation for accurate prediction of disasters in deep-buried hard rock tunnels. Base

Images