Taking Nanfen open-pit iron mine in Liaoning Province as the engineering background, this study analyzes the effect of water-rock circulation on the mechanical properties of rock through a combination of macro-mechanical experiments and microstructure tests in the laboratory. Uniaxial compression experiments and acoustic wave tests are used to determine the degradation law of the mechanical properties of chlorite under the periodic action of water. The experimental results show that dry-wet cycles have a continuous and gradual effect on the rock sampled: Its uniaxial compressive strength, elastic modulus, and acoustic velocity all decrease gradually with an increase in the number of cycles. After 15 wet-dry cycles, the uniaxial compressive strength and elastic modulus of the rock decreased by 34.21% and 44.63%, respectively. Electron microscope scans of the rock indicate that the particle size, characteristics, and pore distribution at the rock surface had changed significantly after water-rock interaction. Finally, a drainage system and sliding force monitoring devices have been arranged at the mine site that can effectively reduce the impact of water-rock interaction on the stability of the mine. This combination of macro-experiments and micro-analysis allowed the weakening effect of dry-wet cycles on slope rock to be studied quantitatively, providing a theoretical reference for stability evaluation in geotechnical engineering.

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Physical modeling of the underground roadway in horizontal strata is carried out by using a newly developed physical modeling approach, the so-called "physically finite elemental slab assemblage (PFESA)." e numerical 2D digital image correlation (DIC) technology is used to carry out the real-time monitoring of the surface displacement of the model in the experimental process, and the axial force monitoring devices called the small bolt (SB) and small constant resistance bolt (SCRB) are designed for the realtime detection of the roadway mechanics data. e displacement information of the whole physical model experiment process is obtained through the DIC technology. e SCRB can be well used to the mechanical monitoring of the deformation and failure of the roadway, though the analysis of the displacement and mechanical monitoring data can get that the change of the mechanical monitoring data of SCRB in advance of the displacement, the information of instability destruction precursor in roadway surrounding rock is the continuous increase of mechanical monitoring value in a short time. e experiment provides reference for the stability monitoring and early warning of the roadway surrounding rock based on a constant resistance and large deformation rock bolt (CRLB).