Abstract Frequent rockfall events at the Huashiya cliff near the dam site of Jinsha Hydropower Station poses great threats to construction projects along the Jinsha River. In order to protect the construction area, a comprehensive analysis of rockfall hazard was carried out including field survey, numerical simulation, quantitative assessment and mitigation strategy. High resolution Digital Terrain Model (DTM) was created by Terrestrial Laser Scanning (TLS), then used for the identification of rockfall sources and simulation of rockfall run-out behaviours. Approximately 60 rockfall simulations were conducted to analyze the interaction between rockfall block and protection nets. Quantitative assessment of rockfall hazard was then made to visualize the distribution and hazard of rockfall. The difference between the 60 rockfall simulations was quantified through Rockfall Interception Ratio (RIR) and the Energy Ratio of Overflying Rockfall (EROR). By integrating RIR, EROR and cost, the performance of protection measures were quantitatively assessed. Then, an optimization strategy was proposed to improve the cost-efficiency of the protection system. At the end of this paper, some problems that can be encountered when creating DTM and hazard maps were discussed, and some advices for designing passive protection system were introduced.

中文翻译：

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西南华石崖落石灾害定量评估及防护系统优化策略

摘要 金沙水电站坝址附近的花石崖崖壁频繁发生落石事件，对金沙江沿岸建设项目构成重大威胁。为保护施工区，开展了包括现场调查、数值模拟、定量评估和减灾对策在内的落石灾害综合分析。高分辨率数字地形模型 (DTM) 由陆地激光扫描 (TLS) 创建，然后用于识别落石源和模拟落石跑动行为。进行了大约 60 次落石模拟，以分析落石块和防护网之间的相互作用。然后对落石危害进行定量评估，以可视化岩崩的分布和危害。60 次落石模拟之间的差异通过落石截留率 (RIR) 和飞越落石的能量比 (EROR) 进行量化。通过综合 RIR、EROR 和成本，定量评估保护措施的性能。然后，提出了一种优化策略，以提高保护系统的成本效益。在本文的最后，讨论了在创建 DTM 和危险地图时可能遇到的一些问题，并介绍了设计被动防护系统的一些建议。