Affected by global warming, extreme rainfall events occur frequently across China, leading to the frequent occurrence and chain development of geological disasters such as landslides and debris flows. Research findings in recent years indicate that multiple factors, including topography, exert an amplification effect on the destructive power of geological disaster chains. These phenomena are particularly pronounced in the Loess Plateau region and have resulted in severe casualties and economic losses. To investigate the amplification effect of topographic factors on loess disaster chains in the Loess Plateau region, this paper takes a multi period loess disaster chain located north of Beilei Village, Heyang County, Weinan City, Shaanxi Province, as a case study. Utilizing a PFC-FLAC coupled simulation method, it analyzes the topographic amplification effect and superposition amplification effect of multiple-source landslides over a temporal scale. Subsequently, it couples a CFD module to investigate the influence of rainfall on loess landslides. The simulation reproduced the evolution of the study area over the past decade and explored the impact of the loess disaster chain on the sliding path during its movement process. It discovered the disaster chain formation pattern under the collision and superposition of multiple-source landslides; furthermore, the topographic gradient and superposition effect amplify the loess disaster chain. This study reveals the evolutionary process and amplification effects of the loess disaster chain in the study area. The new technologies and methods involved can provide references for the theoretical research and prevention of geological disaster chains in other regions.
 

amplification effect,pfc-flac,the loess disaster chain