Low-field nuclear magnetic resonance stereoscopic monitoring method for water disaster risks

Abstract

The invention discloses a low-field nuclear magnetic resonance stereoscopic monitoring method for water disaster risks. The method is suitable for early warning of water disasters such as water bursting and mud bursting in an urban underground space or tunnel construction process and full-life-cycle three-dimensional monitoring and early warning of displacement settlement and visible risks in operation after a tunnel is opened. In the construction stage, firstly, drill holes with different angles are drilled in an underground space or a tunnel construction face, a rock core is obtained, lithology of surrounding rock is obtained, and whether a tectonic zone exists in front or not is judged; and low-field nuclear magnetic resonance miniature sensors are sent into the drill holes for measurement, and an early warning threshold value and a safety evaluation criterion for inducing the water disaster are constructed by using the obtained nuclear magnetic water signal and the lithology of the surrounding rock. After underground space or tunnel construction is completed, surrounding drill holes are formed, low-field nuclear magnetic resonance miniature sensors are pre-buried, an inspection camera and an optical fiber strain sensor are matched, space distribution, displacement settlement and visible risks of water in surrounding rocks are monitored in real time through 5G signals, and safe operation of a tunnel is effectively guaranteed.

Description

Technical field [0001] The present invention relates to a hydrodynamic solid-state monitoring method, especially for real-time monitoring and early warning of urban underground space or tunnel in the tunnel, and the lane risk of the tunnel operation, and is a water shortage risk monitoring technology. . Background technique [0002] With the acceleration of urbanization in my country, the urban space or tunnel development in my country's basic construction is increasing. In the construction of urban underground space or tunnel, there is a certain region of a certain region in the underground space or tunnel in the underground space or tunnel to induce a large number of multi-scale pore cage structures, while the regionality of the formation water may be due to Safety water column has caused a stress concentration, and the safety water column breaks under the dual action of pressure water and ground stress, and the formation water will move along the fracture cracking, resulting i...

AI Technical Summary

Problems solved by technology

However, in the construction of urban underground space or tunnels, due to the disturbance of excavation, there will be plastic damage in a certain area around the underground space or tunnels, which will induce the development of a large number of multi-scale porous and fissure structures, and the regional occurrence of formation water may be caused by If the safe water column is too narrow, the stress will be concentrated, and the safe water column will break under the dual action of pressure water and ground stress. Serious casualties and economic losses

At present, for the prevention and control of water and mud inrush accidents, for example, the traditional leakage detection method is difficult to achieve integral coverage monitoring, which is prone to safety hazards due to missed detection; the detection equipment of electric and magnetic methods is huge, the operation is relatively complicated, and the workload is heavy. Large; the tracer method requires drilling tracers or drilling temperature measurement, which is difficult in some areas; the flow field method can only find the leakage point, and cannot measure the distribution of the leakage body inside the anti-seepage body situation; the optical fiber used in the distributed optical fiber temperature sensing method is relatively sensitive to stress, and there are great difficulties in actual laying

At the same time, most of these methods use spot checks for detection, which lack timeliness for the early warning of instantaneous water inrush accidents.

[0003] On the other hand, after urban underground spaces or tunnels are put into use, there are still water leakage problems, which will cause cracks in the tunnel structure and corrosion of internal structure decoration, resulting in shortened service life of auxiliary equipment in the tunnel, reduced train operating efficiency and safety, and seriously casualties and property damage

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