Construction method of anchor cable for prestressed grouting bird cage on floor of roadway

Abstract

The invention relates to the technical field of coal mine roadway, in particular to a construction method of an anchor cable for a prestressed grouting bird cage on the floor of a roadway. The methodincludes the steps of pre-grouting a floor broken coal rock mass, drilling a floor anchor cable hole on the floor coal rock mass after the pre-grouting, inserting the bird cage anchor cable into the floor anchor cable hole, pouring a precast cement slurry into the floor anchor cable hole, after a preset time passes, stably anchoring a bird cage end of the bird cage anchor cable, stretching, pre-tightening and locking the bird cage anchor cable, and grouting the floor anchor cable hole. The construction method can solve the problem of pucking in a coal mine effectively and economically, under the condition of ensuring the anchoring force of the bird cage anchor cable and the length of a free section, spread a pre-tightening force applied to a wider range of a rock mass, through grouting, restore the integrity of broken surrounding rocks around the bird cage anchor cable so that the pre-stress can spread better, improve the shear resistance of the bird cage anchor cable, and prevent thecorrosion of the anchor cable.

Description

technical field [0001] The invention relates to the technical field of coal mine roadways, in particular to a construction method for prestressed grouting birdcage anchor cables on the bottom plate of the roadway. Background technique [0002] The bottom heave control of coal mine roadway has always been a difficult problem in roadway support. Since the floor is the weakest link of the whole roadway support, under the influence of high stress and dynamic pressure, the surrounding rock of the roadway continuously moves to the roadway floor, resulting in the uplift of the floor. At the same time, since the direct floor of the roadway is generally low-strength mudstone, which contains a large amount of illite, kaolin, and montmorillonite, when it encounters water, this type of rock begins to expand rapidly, which also causes floor drums. [0003] At present, there are two main methods of controlling the floor drum in coal mine roadways: the first is to use U-shaped steel to ma...

AI Technical Summary

Problems solved by technology

Moreover, because it is passive support, the effect is not ideal, and the cost and labor intensity are high; the second is to not support the bottom plate, and when the bottom plate bulges, the bottom is lifted circularly, which causes the surrounding rock of the two sides The continuous transfer to the bottom plate further leads to the failure of the two sides of the support, and large-area deformation of the entire roadway

In addition, uninterrupted bottoming wastes a lot of manpower and material resources, which affects the normal production of coal mines

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