Design method of yieldable anchor rod adapting to large deformation of weak surrounding rock

Abstract

The invention relates to a design method of a yieldable anchor rod adapting to large deformation of weak surrounding rock. The design method comprises the following steps that 1, a yieldable componentwith adjustable yieldable loads is manufactured, wherein the yieldable component is composed of a hollow shell and a force transmission shaft, a piston at one end of the force transmission shaft is located in the hollow shell, the hollow shell is filled with hydraulic oil, and a pressure limiting valve is arranged; 2, the relation between the yieldable loads and the adjustment amount of the pressure limiting valve is determined; 3, when the yieldable component is applied to a roadway or tunnel, the yieldable component and an anchor rod body are assembled according to the designed yieldable loads, the maximum yieldable amount and the yieldable position; and 4, the surrounding rock is punched, then the anchor rod is anchored into the surrounding rock through an anchoring agent, then a limiting supporting plate is mounted, and finally the anchor rod is fixed through a limiting bolt. Based on the structural characteristics of the yieldable anchor rod, three yieldable anchor rod design parameters, namely, the yieldable loads, the yieldable position and the maximum yieldable amount can be adjusted at any time and any place, and the characteristic of meeting the supporting and design requirements of different weak rock tunnel surrounding rock yieldable anchor rods is achieved.

Description

technical field [0001] The invention relates to a bolt supporting structure for a large deformation roadway or a tunnel, in particular to a yielding bolt design method suitable for large deformation of weak surrounding rock. Background technique [0002] In deep-buried roadways and tunnels, the weak surrounding rock often undergoes large time-dependent deformation after excavation. The traditional rigid support system (ordinary anchor rod + steel arch frame) has too much rigidity of the overall support structure, which causes the support system to undertake too large a proportion of the excavation and release load of the surrounding rock at the initial stage of deformation of the surrounding rock, and does not fully utilize the rock. The self-supporting capacity of the body, and the problem of yield failure of the supporting structure when the load exceeds the limit. Therefore, for such deep-buried roadways and tunnels that are prone to large deformation, the traditional ri...

AI Technical Summary

Problems solved by technology

[0003] The existing ordinary bolts have low elongation and are not suitable for large deformation conditions of the surrounding rock; the yielding load, yielding amount and yielding position of the existing yielding anchors have been fixed during processing and forming, and cannot be carried out on the construction site. free adjustment

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