Structural Optimization and Energy Absorption Characteristics of Double-Layer Variable-Diameter Energy-Absorbing Components for Anti-Impact Brackets

Overview

This research addresses the mitigation of impact ground pressure on hydraulic supports in deep roadway reinforcement through the development of double-layer variable-diameter energy-absorbing components. Building on prior work with single-layer variable-diameter structures, the study proposes an enhanced double-layer configuration designed to improve energy absorption capacity. The investigation focuses on tubular components with different cross-sectional geometries, specifically examining combinations of corrugated and circular tubes. The primary objective is to optimize structural parameters to achieve superior energy absorption performance and enhanced stability under axial compression loading conditions relevant to anti-impact bracket applications in underground mining environments.

Methods and approach

The study employed energy methods to analyze energy dissipation theory for expansion and reduction deformation in tubular components with varying cross-sections. Bearing capacity formulas were derived for stable diameter reduction processes under different combinations of corrugated and circular tubes. Numerical simulations were conducted to evaluate eight types of energy-absorbing component configurations, yielding energy absorption curves, bearing capacity curves, and deformation patterns. The SBY-type configuration, comprising an inner corrugated tube and outer circular tube, was identified through comparative analysis. Key structural parameters, including inner tube thickness, outer tube thickness, corrugation radius, and base chamfer angle, were investigated for their influence on energy absorption characteristics. A Latin hypercube sampling scheme was implemented, and optimization was performed using a Kriging surrogate model coupled with a multi-objective particle swarm optimization algorithm. The optimized design was validated through axial quasi-static compression tests to verify numerical and optimization results.

Key Findings

The comparative analysis of eight energy-absorbing component types identified the SBY-type double-layer configuration as exhibiting superior energy absorption performance. Four structural parameters were determined to have the most significant effects on energy absorption characteristics: inner tube thickness, outer tube thickness, corrugation radius, and base chamfer angle. The optimization process yielded an optimal parameter combination with inner tube thickness of 6.0 mm, outer tube thickness of 2.9 mm, corrugation radius of 6.9 mm, and base chamfer angle of 40°. Experimental validation demonstrated that the optimized double-layer variable-diameter component achieved a 54.2% increase in total energy absorption, 55.6% increase in specific energy absorption, and 43.2% increase in average bearing capacity compared to baseline configurations. The load standard deviation increased by 59.5%, indicating enhanced stability in the energy absorption process.

Implications

The optimized double-layer variable-diameter energy-absorbing component demonstrates substantial improvements in energy absorption capacity and stability, enhancing the reliability of yielding anti-impact processes in hydraulic support systems. The significant increases in total and specific energy absorption, combined with improved bearing capacity and load consistency, indicate that the SBY-type configuration offers a viable solution for mitigating destructive impact ground pressure effects in deep roadway applications. The validated design methodology, integrating energy-based theoretical analysis, numerical simulation, and multi-objective optimization, provides a framework for developing energy-absorbing components in underground mining support structures. The research establishes theoretical foundations and design parameters for hydraulic support systems operating under high-impact loading conditions in deep mining environments, contributing to improved safety and structural integrity in roadway reinforcement applications.