Research status and prospects of energy-absorbing anchor support equipment

Energy-absorbing support is an important prevention and control technology in underground rock engineering to enhance the stability of surrounding rock and prevent disasters such as rock burst. The core principle of energy-absorbing support technology is to effectively absorb or dissipate energy through specific structural designs when the rock mass undergoes displacement or deformation, thereby reducing engineering failure and accidents caused by impact loads. Energy-absorbing bolts are a common form of energy-absorbing support. This technology combines the surface surrounding rock with the deep stable rock mass through bolts and generates prestress within the surrounding rock to absorb or dissipate energy and prevent mine disasters. This flexible support method is suitable for the support of various environments in tunnel and has been widely used in the prevention and control of mine disasters. This investigation reviews over 30 representative energy-absorbing bolt designs since 1968, classifying them into two major types: structure and material. It focuses on analyzing the working principles and design advantages of eight typical energy-absorbing bolts and points out the deficiencies in the application of existing energy-absorbing bolt support in terms of safety and intelligence. Combining the valuable research results of predecessors with the current demands of high-strength and intelligent support in deep mines, an intelligent early warning negative Poisson’s ratio structure energy-absorbing bolt is proposed. This bolt utilizes a negative Poisson’s ratio energy-absorbing structure to achieve an increased resistance effect and has the characteristics of bidirectional constant resistance energy absorption and bidirectional monitoring and early warning. It can meet the demands of strong resistance support and visual early warning in complex nonlinear soft rock tunnel, which is conducive to accelerating the integration of support systems and promoting the development of safe and intelligent mines. Finally, this study provides an outlook on the optimization and innovation trends of energy-absorbing bolt support equipment.