Test bed for installing and pre-tightening of anchor rod and test method

Abstract

The invention relates to the technical field of mine supporting, in particular to a test bed for installing and pre-tightening of an anchor rod and a test method. The test bed comprises the anchor rod for mine supporting and further comprises a pre-tightening device, a stretching device, a work test bed body, a dynamic torque sensor, a static torque sensor and a load sensor. One end of the anchor rod is anchored into a drill hole model of the work test bed body. The pre-tightening device is used for exerting pre-tightening force to the anchor rod. The stretching device comprises an impact beam and a stretching top beam, and the other end of the anchor rod is fixed to the impact beam. The stretching top beam corresponds to the impact beam and is used for preventing the impact beam from moving in the axial direction of the anchor rod. The installing and pre-tightening process of the anchor rod is simulated in a laboratory through the test bed, transformation of the tightening torque of an anchor rod nut and the axial pre-tightening force of the anchor rod is accurately tested, the torque borne by a rod body is tested after the anchor rod is installed and pre-tightened, and the test bed for installing and pre-tightening of the anchor rod is of great importance in deepening the mechanism study of anchor rod supporting and ensuring engineering safety.

Description

technical field [0001] The invention relates to the technical field of mine support, in particular to a test bench and a test method for bolt installation and pretightening. Background technique [0002] At present, bolt support has become a safe and efficient main support method for coal mine roadways, and has been widely promoted and applied in coal mine roadways in my country. Bolt support is to anchor the bolt in the coal rock body, tighten the nut at the end of the rod, apply prestress to the surrounding rock, and restrain the deformation, separation, expansion and slippage of the surrounding rock of the roadway. [0003] During the bolt support construction, after the bolt is anchored, install the anchor tray, self-aligning spherical washer, anti-friction gasket and other supporting components at the end of the bolt exposed at the hole, and install and tighten the nut at the end of the bolt. The torque of tightening the bolt nut is converted into the axial tension of ...

AI Technical Summary

Problems solved by technology

However, the disadvantages of the downhole test are: the torque for tightening the nut cannot be accurately tested, the conversion relationship between the nut torque and the pre-tightening force of the bolt cannot be determined, and the installation torque borne by the bolt body cannot be tested.

However, the disadvantage of the laboratory test is that the indoor single test only reflects the mechanical index of the anchor material under a single stress condition. Due to the lack of a test bench for simulating the actual installation of the anchor, the conversion between the nut torque and the preload of the anchor cannot be accurately tested. relationship, and it is impossible to test the torque that the anchor body bears during the installation process

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