Application of Wireless Sensor Network in Rock Bolt Pulling Force Distribution Pattern Monitoring

Abstract

The application of rock bolting in the reinforcement of underground engineering and tunnel engineering is becoming more extensive, and the stress distribution pattern of rock bolt is a necessary means for quality monitoring. To investigate the stress characteristics of the rock bolt during usage, this paper tests the stress and strain changes of the full-length anchoring rock bolt and the end anchoring rock bolt under the action of pulling force based on the wireless sensor network (WSN) technology, it analyzes the strain characteristics of the exterior of the rock bolt. The research shows that the axial force of the full-length anchoring rock bolt increased with the increase of the load, when the load reached 28MPa, the bolt at the end of rock bolt rod slid; the longitudinal strain of the base of the end anchoring rock bolt was only affected by the top pressure, the shear stress of the middle hollow anchoring section was 0, and the axial strain was the largest; for the full-length anchoring rock bolt, the shear stress was distributed along the whole length of the rod body, and the strain value at the front end was the largest; for the two anchoring methods, both the wavelength drift of the fiber Bragg grating (FBG) measuring points on the rod body of rock bolt and the strain of the base increased with the increase of the load. This study lays a theoretical foundation for long-term quality monitoring and evaluation of rock bolting based on WSN.