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According to the invention developed at AGH, a telescopic bolt consists of at least two telescopically interconnected, pivotally coupled segments, wherein the second segment between the piston and end wall of the first segment contains at least one element capable of limited energy storage with a shape similar to a hollow circular cylinder, and the through holes in the jacket of the first segment are located in a section of the element corresponding to its length.
The proposed rock bolt construction will enable bolting with long rock bolts even in workings with ceilings lower than the length of the bolt, using simple technical means. At the same time it will be able to better move the dynamic load of the rock mass.
It is preferred for the element capable of energy accumulation to be a chemically hardening resin cartridge, which will serve as an additional connection of the bolt to the rock mass at a given load, while stiffening the bolt at the same time.