Active expansion type tube seam anchor rod, and preparation and use methods of active expansion type tube seam anchor rod

Abstract

Disclosed are an active expansion type tube seam anchor rod, and preparation and use methods of the active expansion type tube seam anchor rod. The active expansion type tube seam anchor rod is composed of a rod body, a bearing device at the rear end of the rod body, and a self-expansion device arranged in the rod body. Two longitudinal cutting seams are formed in the front end of the rod body, wherein a 120-degree included angle is formed between each longitudinal cutting seam and a tube seam. The self-expansion device is composed of a self-expansion body and an axial expansion constraint device. The self-expansion body comprises an agent barrel filled with an expanding agent, and a protection barrel arranged on the agent barrel in a sleeving mode and provided with a water permeable holein the outer wall. The expanding agent is prepared from CaO, bentonite, kaolin, a water reducing agent and a hardened material. Roadway surrounding rock is anchored by the active expansion type tube seam anchor rod, even if a tube seam anchor rod is selected, large anchoring force can also be achieved, wherein the difference between the diameter of the tube seam anchor rod and the hole diameter ofa drilled hole is not greater than 2 mm, thus the anchoring effect can be ensured, and the purposes of lowering the mounting difficulty of the tube seam anchor rod, increasing the mounting speed of the anchor rod and improving the mounting efficiency of the anchor rod can be achieved by decreasing the difference between the diameter of the tube seam anchor rod and the hole diameter of the drilledhole.

Description

technical field [0001] The invention relates to the field of geotechnical engineering support, in particular to an active expansion pipe seam bolt and its preparation and use method. Background technique [0002] The pipe seam anchor belongs to the friction type full-length anchoring type prestressed anchor, which has the advantages of simple structure, convenient installation, low price, and fast bearing. Since the bolt came out, it has been widely used in the field of underground engineering support, especially the support and reinforcement of soft rock wells. The conventional pipe seam anchor rod is composed of a rod body with a pipe seam longitudinally along the entire length and a supporting component (including a tray and a retaining ring) installed at the rear end of the rod body. The outer diameter of the rod body is 2 to 3 mm larger than the diameter of the drilled hole. and gradually shrinks longitudinally. The anchoring principle is to radially compress the rod ...

AI Technical Summary

Problems solved by technology

Its shortcoming is that because the pipe joint anchor itself does not change, not only does not solve the problem of the installation difficulty of the pipe seam anchor, but also because it is difficult to push the wedge into the pipe joint through external force, which further increases the complexity of the construction , reduce construction efficiency

Its advantage is that it can enhance the friction force between the anchor rod and the surrounding rock and the anchoring force at the end; the disadvantage is the same as that of the pipe seam anchor rod disclosed in the CN104846821A patent document, and the processing procedure is cumbersome; and it can only increase the friction between the rod body and the rock wall coefficient, but the pressure between the hole wall and the rod body does not change, and the anchoring effect is limited

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