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The dynamic effect is a very important issue widely debated by scholars when studying the genetic and disaster-causing mechanisms of earthquake-triggered landslides. First, the dynamic effect mechanism and phenomena of earthquake-triggered landslides were summarized in this paper. Then, the primary types of dynamic effects were further used to interpret the Mogangling landslide in Moxi Town of Luding County, China. A field investigation, remote sensing, numerical calculation and theoretical analysis were carried out to illustrate the failure mechanism of slope rock masses affected by earthquakes. The interaction between seismic waves and slope rock masses and the induced dynamic effect of slope rock masses were primarily accounted for in the analysis. The slope topography, rock mass weathering and unloading characteristics, river erosion, regional seismogenic structure, and rock mass structure characteristics were also discussed. The results showed that the formation of the Mogangling landslide was mainly related to the high amplification effect of seismic acceleration and back slope effects, interface dynamic stress effects, and double-sided slope effects of seismic waves caused by the catastrophic Ms 7.75 Moxi Earthquake in 1786. The principles for the site and route selection of large-scale infrastructure in the planning stage and the scientific prevention of seismic geological disasters were proposed on the basis of the dynamic effect of earthquake-induced landslides. [ABSTRACT FROM AUTHOR]

Mining-induced disturbance to stress fields can lead to many engineering disasters such as rock bursts, roadway collapses, and coal and gas outbursts. The evolution characteristic of abutment pressure during the mining process is of great significance for prevention of engineering disasters. Based on a case study of No.12526E Panel in Xieqiao coalmine of Huainan mining area in China, this paper investigated the evolution characteristic of abutment pressure during the retreat mining process. A field measurement was performed using three-dimensional (3D) pressure sensor, and the abutment pressure was continuously monitored during the mining process. The monitoring results indicate that the abutment pressure curve can be divided into strong interference area and weak interference area. Further, the evolution characteristics of abutment pressure during the retreat mining process were simulated using a 3D discrete-element program. Periodic caving characteristics of rock strata were obtained, and the major causes of stress concentration and the bearing stress inflection point were analyzed. With the periodic caving of the overlying strata, the stress inflection point appears, and fracture cracks are generated and hinder stress recovery. Finally, the detailed dynamic evolution process of the abutment pressure as well as the deformation and caving characteristics of the overlying strata of the No.12526E Panel were analyzed. The coal and rock near the mined-out area undergo a sharp stress concentration and reduction, which would lead to damage to the rock mass near the mined-out area. [ABSTRACT FROM AUTHOR]