Multi-stage anchoring mortar bolt and its anchoring method

Abstract

The invention discloses a multi-section anchoring type mortar anchor rod and an anchoring method thereof. The multi-section anchoring type mortar anchor rod comprises anchor rod bodies and an orifice pre-tightening instrument, wherein free sections are arranged on the anchor rod at intervals; sections of plastic sleeves are sleeved on the anchor rod bodies, so as to form the free sections; the two ends of the plastic sleeves are plugged or tightened by using flexible gaskets; the anchor rod bodies sleeved with the plastic sleeves are arranged as the free sections and the rest anchor rod bodies are arranged as point anchoring sections, so that the anchor rod bodies are divided into a first free section, a first point anchoring section, a second free section, a second point anchoring section, a third free section and a third point anchoring section in turn from an orifice; the first free section is located in a loosening area of the surrounding rock; the third point anchoring section is located in an elastic area of the surrounding rock; the rest sections are located in a plastic area of the surrounding rock. The quantity and lengths of the point anchoring sections and the free sections can be adjusted according to the pressure distribution characteristics of the surrounding rock; the loads are scattered; ultra-strong stress concentration is prevented from generating on the end part of the anchor rod; the rod body is prevented from being broken or an anchored element is prevented from being taken out.

Description

technical field [0001] The invention relates to anchor rods for strengthening various rock mass engineering such as mine roadways, traffic tunnels, underground engineering, rock mass slopes, etc., and is especially suitable for reinforcing anchor rods for soft rock engineering. Background technique [0002] At present, the bolt anchoring method is mainly an end-anchor anchor or a full-length anchor anchor, which are composed of an anchor body, an orifice pretensioner and an anchoring agent. The technology related to the present invention is a full-length anchor bolt. The full-length anchor bolt injects mortar into the full hole, and an anchoring agent (mortar anchor for short) is provided between the anchor body and the full hole wall. This kind of full-length anchoring form will cause the shear damage of the anchoring medium due to the cumulative deformation transfer, resulting in the failure of the bolt support. This bolt failure phenomenon is particularly prominent in so...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the technical problem that the existing bolt cannot adapt to the deformation and displacement of the surrounding rock and is broken and fails, the present invention proposes a multi-stage anchored mortar bolt and an anchoring method for the bolt

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