Study on Infrasonic Signal Characteristics and Energy Characterization of Damage and Failure in Red Sandstone Under Uniaxial Cyclic Loading and Unloading Conditions  
[PERSON]  
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wave is 0.01-20 Hz [5; 6]. It has the characteristics of low frequency, long wavelength, long propagation distance, and low attenuation and does not need coupling contact when monitoring rock stability [7]. It is suitable for use in complex terrain environments, such as mines. Therefore, it is of great significance to study the evolution mechanism and precursor characteristics of the rock damage destruction process by using infrasound technology for the early warning and analysis of rock damage.  
In recent years, a large number of scholars have used infrasound technology to study the infrasonic signal characteristics of coal and rock stability monitoring and the deformation damage process. [PERSON] et al. conducted uniaxial compression tests on six kinds of rocks, detected the low-frequency infrasonic signals generated in the process of micro-fracturing, and analyzed the characteristics of infrasonic signals in the process of rock fracturing [8]. [PERSON] et al. conducted compression failure tests on sandstone by using laboratory tests, collected infrasonic signals during rock deformation and failure, and analyzed the energy characteristics of abnormal signals [9]. [PERSON] et al. analyzed the corresponding relationship between infrasonic signal and loading stress during the uniaxial compression of coal and rock. Before the instability and failure of coal and rock occurred, significant infrasonic signals were generated [10; 11]. [PERSON] et al. analyzed the variation characteristics of sound energy in coal samples during uniaxial loading, and with the increase in strength, the proportion of low-frequency sound waves gradually increased [12; 13; 14]. [PERSON] et al. used infrasound methods to study the mechanical characteristics of cemented tailings backfill and rock damage processes at different curing ages [15; 16; 17]. [PERSON] et al. deployed seismic and infrasound sensors on cliffs for the in situ detection and localization of rockfalls at a distance [18]. [PERSON] et al. conducted infrasound experiments to study the damage process of granite under dynamic uniaxial compression [19]. [PERSON] et al. investigated the relationship between infrasonic signals characteristics and loading rate during the uniaxial compression damaging of marble [20]. Most scholars analyzed the infrasonic parameter characteristics of coal, rock, and backfill during the damage process under different loading conditions, which is best for promoting the application of infrasound technology in rock engineering; however, few studies have been carried out on the characterization of the damage evolution of red sandstone based on infrasonic energy under uniaxial loading and cyclic loading and unloading.  
This study investigates the infrasonic signal characteristics and damage evolution mechanisms of red sandstone under loading conditions, and key parameter characteristics such as mechanical characteristics, infrasonic amplitude changes, infrasonic energy rate, and cumulative energy during uniaxial loading and cyclic loading and the unloading of red sandstone are analyzed. On the basis of infrasonic energy being used to characterize rock damage, the damage evolution law of red sandstone is further studied, which provides theoretical support and technical guarantee for the stability assessment and instability warning of rock engineering.