黄土地震滑坡成灾机理与风险评估

黄土高原是我国强震多发、特大地质灾害频发的主要地区之一，地震诱发滑坡是造成人员伤亡和经济损失的主要原因。本项目拟针对黄土高原滑坡灾害广、频、重的现状，聚焦地震诱发黄土滑坡风险，构建黄土高原地震滑坡与强震动记录数据库，建立不同发震断层性质地震动衰减关系，阐明黄土斜坡失稳运动过程和滑动方式，揭示不同发震断层性质的地震滑坡效应及成灾模式；分析总结典型黄土斜坡的损伤失稳与触发致灾机制，研发强震诱发黄土滑坡的时空动态演化数值模拟方法，并探讨地震和水耦合交互作用下的黄土滑坡变形-失稳-滑动机制及长期效应；建立多指标多水准黄土地震滑坡危险性综合评价模型和危害性评估模型，提出黄土地震滑坡风险等级标准，建立黄土地震滑坡风险评估理论体系，制定风险防控措施，并编制应用示范区划图。预期成果对有效降低我国黄土地区城镇和重大基础设施高地震灾害风险、提升区内地震灾害综合防御能力具有重大的科学意义和应用价值。

The Loess Plateau is one of the main areas in China where earthquakes and catastrophic geological disasters occur frequently. Especially the earthquake-induced landslides have been proved to be the main cause of casualties and property losses. In view of the current situation of landslide disasters with wide range, frequent occurrence and serious consequences in the Loess Plateau, and the potential high risk of loess landslides induced by earthquakes, this project will construct a set of databases of seismic landslides and strong motion records in this area. The attenuation relationship of ground motions with different characteristics of seismogenic faults will be established，the instability movement process and sliding mode of loess slopes will be illustrated, and the disaster mode of loess seismic landslides will be revealed under the effects of seismogenic faults as well. The damage instability and triggering mechanism of disaster-causing of typical loess slopes will be analyzed and summarized, and the numerical simulation method of time-space evolution of loess landslides induced by strong earthquakes will be developed. Meanwhile, the instability evolution law and long-term effect of loess slopes under the interaction of earthquakes and water will be studied. On this basis, the risk evaluation model and hazard assessment model for seismic loess landslides with multi-level and multi-index will be established. Moreover, the risk grade standards for seismic loess landslides will be put forward, and a theoretical system will be created accordingly. The measures of risk prevention and control can be formulated and the corresponding demonstration zoning map will be compiled. The results are of great scientific significance and application value to effectively reduce the high risk of earthquake disasters of cities, towns and major infrastructures in the Loess Plateau and enhance the comprehensive ability of earthquake disaster prevention in the area.