Abstract:
In the rock burst mines, mastering both the mechanical and modal response characteristics of advanced hydraulic supports is the basis and premise for the selection and optimization of roadway advanced hydraulic supports. Research was conducted on the response characteristics of unit-type energy-absorbing and anti-impact hydraulic supports under impact loads to address the issue of enhancing anti-impact performance. Using the nonlinear finite element analysis software ABAQUS/Explicit, the numerical calculation model of the unit type energy-absorbing and anti-impact hydraulic support was established. The vertical impact test was carried out on the energy-absorbing and anti-impact supports by numerical simulation, both the mechanical and modal response characteristics of the energy-absorbing and anti-impact supports were analyzed, and the energy-absorbing characteristics, natural frequency, and easily deformable components of the unit type energy-absorbing and anti-impact hydraulic support were explored. The results show that in terms of mechanical response characteristics, under the impact load, the unit type energy-absorbing and anti-impact support exhibits a good comprehensive efficiency of “reducing pressure to drop resistance, damping to mitigate amplitude, and absorbing energy to stop impact”. During the entire impact process, the energy-absorbing and anti-impact support absorbed a total of 2.30 MJ of energy, and the plastic deformation energy consumption of the energy absorber accounted for 40% to 50%. In terms of modal response characteristics, the natural frequency of the unit type energy-absorbing and anti-impact hydraulic support is 665.37−
3280.5 Hz, which is relatively high. The support has good frequency avoidance adaptability for medium-high frequency types of rock burst, such as brittle fracture of the near-field roof or instability of coal compression. Through numerical simulation calculations, it is found that the two pillars of the hydraulic support and the pillar guard plate are the most susceptible components to vibration deformation. When designing pillars, it is important to avoid vibration deformation at the 1st, 2nd, 4th, 5th, 6th, and 9th order vibration frequencies, especially in the frequency avoidance design of the main vibration mode; When designing pillar guard plates, it is important to avoid vibration deformation and its deformation trend at the 1st, 2nd, and 9th order vibration frequencies. The research results can provide technical support for the rational selection and subsequent optimization of energy-absorbing and anti-impact hydraulic supports in roadways.