A detachable hydraulic anchor rod and its support method for steady-state pressure release

Abstract

The invention discloses a detachable hydraulic anchor rod with steady yielding and energy release and a supporting method thereof. The anchor rod comprises an anchor rod body and a hydraulic constantresistance device. The hydraulic constant resistance device comprises a hydraulic cylinder column and a piston. The piston divides the hydraulic cylinder column into a cavity and a hydraulic oil cavity, a telescopic transmission shaft is axially arranged along hydraulic cylinder column in the cavity, a connecting rod is fixedly arranged along the opposite extension direction of the telescopic transmission shaft in the hydraulic oil cavity, the distal end of the connecting rod passes through a hydraulic cylinder opening to be threadingly connected to the front end of the anchor body, the connecting rod is sealingly sleeved in the hydraulic cylinder opening, an automatic liquid discharging device is installed near the hydraulic cylinder opening, the hydraulic cylinder column is also providedwith a liquid injection device, the back end of the anchor rod body is fixedly provided with a stirring head, and the front end of the hydraulic cylinder column is fixedly provided with a tighteningend, a nut and a tray. The piston is driven by the connecting rod to slide to the hydraulic oil cavity such that the telescopic transmission shaft extends with the movement of the piston, the constantresistance large deformation yielding and energy release is achieved, the anchor rod can be disassembled after use and is convenient to use repeatedly.

Description

technical field [0001] The invention belongs to the technical field of mine support, and in particular relates to a detachable hydraulic anchor rod for pressure release in a steady state, and a support method for the anchor rod. Background technique [0002] The excavation of tunnels and other underground projects destroys the stress balance state of the original rock and causes damage to the surrounding rock. Under the action of concentrated stress, the surrounding rock moves and deforms. If effective support is not carried out in time, it will easily lead to project instability and damage. Practice has shown that compared with passive support methods such as scaffolding support (U-shaped steel, I-beam) and masonry support, bolt support can significantly improve the stability of surrounding rock due to the active application of prestress, and is easy to operate , low labor intensity and low cost, so it is widely used in the field. With the exhaustion of shallow resources, ...

AI Technical Summary

Problems solved by technology

However, these bolts mainly achieve different degrees of extension (generally less than 200mm) through the principles of elastoplastic deformation and sliding friction of the rod body and other components. The dual characteristics of deformation cannot achieve the purpose of releasing energy in a steady state, and it is very easy to damage or fail during use

For example, the Chinese patent with the publication number CN101858225A discloses a constant-resistance large-deformation bolt, which deforms through the friction and slippage between the built-in thread structure of the constant-resistance device and the rod body, and is affected by the stress of the non-uniform surrounding rock. It is difficult to produce uniform elastic deformation upwards and it is difficult to maintain constant resistance characteristics

CN107227967A discloses a constant-resistance large-deformation pressure anchor or anchor cable. When the end is anchored, the first-stage constant-resistance hydraulic device is not fixed in the borehole and will not operate. When the force on the anchor reaches the second-stage constant resistance When the working tension specified by the yielding device is reached, the first-stage constant resistance hydraulic device will move together with the anchor (cable) body, so the yielding function cannot be performed, and the second-stage constant resistance hydraulic device and the anchor (cable) will slide by friction Yield pressure, easy to failure and damage under impact dynamic load

Other relevant patents, such as CN203531938U, CN102286975A, CN107893673A and CN103603685A, etc., all have the above-mentioned defects, which are difficult to meet the safety needs of deep buried projects

[0004] In addition, most of the bolts currently used in mines are disposable consumable materials, which cannot be disassembled and recycled after being discarded, resulting in a large waste of resources and potential safety hazards

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