A quick calculation method for surrounding rock stress for deep -buried circular tunnels

Abstract

The invention discloses a quick surrounding rock stress measuring method applicable to buried circular tunnels. The method includes: setting each circle of spallation blastholes, buffering blastholes and smooth blasting blastholes to be detonated in two sections, determining main stress on a tunnel face to determine axial stress of the tunnel according to the maximum main stress on the tunnel face. The quick surrounding rock stress measuring method applicable to the buried circular tunnels has the advantages that conventional blasting operations and vibration monitoring are utilized, no extra equipment is needed, operation is convenient, and real-time and dynamic estimation of the surrounding rock stress close to the tunnel face during blasting construction can be realized. The quick surrounding rock stress measuring method applicable to the buried circular tunnels is mainly applicable to quick measuring of the surrounding rock stress of the deep buried underground constructions in the field of hydropower, communication, mines and the like.

Description

technical field [0001] The invention relates to the technical field of geotechnical engineering, in particular to a method for quickly measuring and calculating surrounding rock stress suitable for deeply buried circular tunnels. Background technique [0002] With the further deepening of hydropower development in Southwest my country and the increasing depth of mining of mineral resources, engineering geological disasters induced by high ground stress during the excavation of deep tunnels are becoming more and more common and serious. In order to predict the occurrence of rock mass instability failure and rockburst, and to provide a basis for rock mass support and reinforcement, it is necessary to dynamically grasp the stress magnitude and direction of the surrounding rock near the tunnel face in real time during cavern construction. The existing in-situ stress measurement methods can be roughly classified into three categories according to their measurement principles: the...

AI Technical Summary

Problems solved by technology

The stress relief method requires operations such as drilling, trapping rock cores, and installing sophisticated electronic instruments. The measurement cycle is long, and it will affect the construction progress when used near the face of the cavern, and cannot meet the real-time dynamic requirements; and due to the deep rock mass High ground stress, severe drilling deformation, and core fractures lead to difficulties in coring, low measurement success rate, and significantly affected the reliability of measurement results

The equipment used in hydraulic fracturing is huge, the drilling diameter is large, the drilling time is long, the measuring instruments are expensive, and the testing cost is high, so it cannot be applied to the rapid measurement of ground stress in the surrounding rock of deep buried tunnels

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