Self-expanding pipe seam anchor rod for surrounding rock large deformation and preparation and using methods of self-expanding pipe seam anchor rod

Abstract

The invention discloses a self-expanding pipe seam anchor rod for surrounding rock large deformation and preparation and using methods of the self-expanding pipe seam anchor rod. An anchor rod comprises a rod body internally provided with self-expanding explosive columns and a tray, resistance increasing seams are formed in the pipe wall, making contact with the self-expanding explosive columns, of the rod body, ring-shaped resistance increasing grooves are formed in the pipe wall of the rod body on the rear parts of the self-expanding explosive columns, the rear end of a threaded rod of the series-wound self-expanding explosive columns penetrates through the tray and is connected with a fastening nut, and the tray is not fixedly connected with the rod body. During using, the self-expanding explosive columns are soaked in water first, then the anchor rod is inserted into a drilling hole, the fastening nut is screwed, thus the tray and surrounding rock wall get close; radial expansion pressure is generated by using size expanding of a hydration reaction of a self-expanding anchoring agent, and the anchoring effect is performed; when lager deformation of surrounding rocks occurs, rock body deformation force is applied to the self-expanding explosive columns through the tray, a fastening bolt and the threaded rod, fiction slippage occurs between the self-expanding explosive columns and the rod body when stress exceeds design resistance, in the process of slippage, constant resistance and yielding can be maintained by the resistance increasing seams and resistance increasing grooves, and the anchoring function can be continuously performed after displacement.

Description

technical field [0001] The invention belongs to the technical field of geotechnical engineering support, in particular to a self-expandable pipe-slit anchor rod which can be used for large deformation of surrounding rock and its preparation and use method. Background technique [0002] Anchor rod is a rod-shaped tensile member made of high tensile strength material, installed inside the rock mass, and used to support building foundation pits, open slopes, tunnels and shafts. Bolt support is to drill holes into the surrounding rock of the roadway and install bolts in the holes to form a stable support belt around the roadway to achieve the purpose of strengthening the surrounding rock. [0003] The pipe-slit bolt is currently the most commonly used support bolt in mines. The diameter of the bolt is larger than the borehole diameter (the diameter of the front end is slightly smaller than the borehole diameter). When in use, the pipe-slit rod body is pushed into the borehole by...

AI Technical Summary

Problems solved by technology

The above-mentioned active expansion pipe joint bolt, because the tray and retaining ring at the end of the bolt are fixedly connected with the bolt, does not have the function of giving way when dealing with the large deformation support of the broken surrounding rock. When the deformation causes the deformation of the surrounding rock to exceed the bearing range of the pipe joint anchor, the rod will be broken, causing the tray and retaining ring to fall off, and the anchor will lose its anchoring effect

Therefore, this active expansion pipe joint bolt cannot adapt to the characteristics of large deformation of deep surrounding rock.

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