Numerical simulation analysis of energy evolution law and distribution characteristics of anchored body unidirectional loading

• Utilizing the embedded Fish language in FLAC 3D and uniaxial compression tests of rock samples, a rock energy model was developed and validated. • An energy evolution model for anchored body was established, revealing the laws of energy evolution and distribution within anchored body. • The load-bearing and energy storage properties of anchor bolts during the loading process of anchored body were revealed. Energy serves as the fundamental driver of material failure, and accurately describing the mechanical properties and energy evolution laws of loaded anchored body is crucial for the stability control of surrounding rock in bolt-supported roadways. Based on uniaxial compression tests of rock samples and utilizing the embedded Fish programming language in FLAC 3D , numerical models of loaded sandstone specimens and energy models were developed. Through a comparative analysis between FLAC 3D numerical simulations and laboratory uniaxial compression test results, the rationality of the energy model was validated, and post-peak strength parameters for the anchored body were established. Employing the PILE and LINER structural elements within FLAC 3D , models for pre-stress diffusion in anchor bolts and energy evolution in anchored body were constructed. These models explored the distribution characteristics of tensile and compressive stress zones within anchored body during pre-stress release, as well as the pressure arch effect. Furthermore, the fracture behavior of anchored body and bolt load characteristics under different support and drilling size and density conditions were analyzed. The study revealed the evolution and distribution patterns of total energy density, elastic energy density and dissipated energy density during both the pre-peak and post-peak stages of anchored body. The mechanical effects and energy evolution laws of anchored body and bolts exhibit distinct stage − specific characteristics.