Abstract
Disintegration and fragmentation effects are ubiquitous in the motion of high-elevation rockslides, capable of altering both the material state and kinematic state of the landslide mass, thereby influencing its energy distribution and dynamic transmission characteristics. To investigate the disintegration and fragmentation characteristics and energy dissipation patterns of high-elevation rockslide debris flows, and to reveal their dynamic transmission mechanisms, large-scale physical model tests were employed, focusing on the effects of block strength, volume, thickness, degree of joint development, and slope gradient in the source area on rock mass disintegration and fragmentation. The results indicate that during dynamic transmission in high-elevation rockslide debris flows, the velocity reduction in the frontal region is significantly less than that in the rear region, the leading edge exhibits distinct "secondary acceleration," and substantial fine particles accumulate at the distal end. The rear portion of the landslide mass demonstrates notable velocity and dynamic transmission effects toward the front, with such effects becoming more pronounced as the degree of fragmentation increases. The disintegration and fragmentation process is accompanied by energy transformation, transmission, and loss, with fragmentation energy consumption accounting for approximately 3.32%–21.03% of the total potential energy under the control of fragmentation degree.
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Preamble
Disintegration and Fragmentation Effects of High-Position Rock Landslide Debris Flows Based on Large-Scale Physical Model Tests
Chen Fei-yu², He Xu-rong², Huo Zi-hao¹, Zhang Shi-lin², Yang Chao-ping¹
(1. Technical Guidance Center for Geo-hazard Prevention, Ministry of Natural Resources, China Institute of Geo-Environment Monitoring, Beijing 100081, China; 2. Faculty of Geosciences and Engineering, Southwest Jiaotong University, Chengdu, Sichuan 610031, China)
Abstract
The disintegration and fragmentation effect is a ubiquitous phenomenon during the movement of high-position rock landslides, fundamentally transforming both the material state and kinematic characteristics of the sliding mass, thereby exerting profound influence on energy distribution and dynamic transmission patterns. To investigate the fragmentation characteristics and energy dissipation mechanisms of high-position rockslide debris flows, this study employs large-scale physical model testing to systematically examine the effects of key controlling factors—including block strength, volume, thickness, joint development degree, and slope gradient—on rock mass disintegration and fragmentation.
Experimental results reveal that during dynamic transmission, the frontal region of the debris flow experiences substantially less velocity attenuation compared to the rear region, with the leading edge exhibiting a pronounced "secondary acceleration" phenomenon while fine particles accumulate extensively at the distal deposition zone. A clear velocity and dynamic transmission effect propagates from the rear to the front of the landslide mass, with the intensity of this effect correlating positively with the degree of fragmentation. The disintegration and fragmentation process involves complex energy conversion, transmission, and dissipation; controlled by the fragmentation intensity, the energy consumed by fragmentation accounts for approximately 3.32% to 21.03% of the total potential energy.
Keywords: high-position rock landslide debris flow; large-scale physical model test; dynamic transmission; disintegration and fragmentation; energy dissipation; engineering