Characteristics，disaster mechanism，prevention and treatment and enlightenment of airport high fill landslide in mountainous area：Taking Panzhihua Airport as an example

ObjectiveDue to the unique engineering geological conditions associated with the mountainous terrain, the construction of airports in such areas has resulted in numerous high-fill slope projects. The primary challenge lies in controlling deformation and ensuring the long-term stability of these high-fill slopes during operation. Taking Panzhihua Airport as a case study, this paper systematically reviews the history of geological hazard history during both the construction and operational phases, and provides a detailed description of the development characteristics of three typical high-fill landslides that occurred during operation. MethodsThrough engineering geological investigations and in-situ geotechnical testing, the causes and evolutionary mechanisms of these high-fill landslides are analyzed, and key technologies for landslide control are proposed. ResultsThe results indicate that the internal causes including topography conducive to surface water concentration and the specific unidirectional gently inclined slope structure with soft upper and hard lower layers that facilitate rainfall infiltration. The triggering factors are characterized by concentrated rainfall, frequent short-term rainstorms, abundant groundwater, and the tendency to accumulate above relatively impermeable layers. The instability evolution mechanism of the high-fill slope at Panzhihua Airport can be summarized as follows: long-term infiltration of heavy rainfall, rising groundwater level, softening and shear strength degradation of the weak interface at the fill-bedrock contact, push-creep sliding, failure of retaining structures, progressive sliding and shearing, overall slope failure. The construction of high-fill slopes in mountainous airports should focus on controlling the shear strength of weak layers at the fill-bedrock interface and implementing underground drainage systems. ConclusionFor remediation, anti-slide piles combined with drainage tunnels or catchment wells were adopted to provide strong support and groundwater drainage. Post-construction monitoring confirms satisfactory drainage performance. The results offer valuable references for the deformation mechanisms and remediation strategies in other high-fill projects.