The basic element in any sustainable dam project is safety, which includes the following safety elements:① structural safety,② dam safety monitoring,③ operational safety and maintenance, and④ emergency planning. Long-term safety primarily includes the analysis of all hazards affecting the project; that is, hazards from the natural environment, hazards from the man-made environment, and project-specific and site-specific hazards. The special features of the seismic safety of dams are discussed. Large dams were the first structures to be systematically designed against earthquakes, starting in the 1930s. How-ever, the seismic safety of older dams is unknown, as most were designed using seismic design criteria and methods of dynamic analysis that are considered obsolete today. Therefore, we need to reevaluate the seismic safety of existing dams based on current state-of-the-art practices and rehabilitate deficient dams. For large dams, a site-specific seismic hazard analysis is usually recommended. Today, large dams and the safety-relevant elements used for controlling the reservoir after a strong earthquake must be able to withstand the ground motions of a safety evaluation earthquake. The ground motion parameters can be determined either by a probabilistic or a deterministic seismic hazard analysis. During strong earthquakes, inelastic deformations may occur in a dam; therefore, the seismic analysis has to be car-ried out in the time domain. Furthermore, earthquakes create multiple seismic hazards for dams such as ground shaking, fault movements, mass movements, and others. The ground motions needed by the dam engineer are not real earthquake ground motions but models of the ground motion, which allow the safe design of dams. It must also be kept in mind that dam safety evaluations must be carried out several times during the long life of large storage dams. These features are discussed in this paper.%对任何蓄水大坝工程的基本性能要求都是安全性，它包括以下安全要素：①结构安全性；②大坝安全监控；③运行安全和维护；④应急计划。长期安全包括：首先，分析影响项目的所有灾害，即自然环境灾害、人造环境灾害、特定项目和特定场地灾害。本文讨论的是大坝地震安全的特点。大坝是自20世纪30年代以来最早开始进行系统性抗震结构设计的建筑物，但由于多数大坝设计采用的是现今认为已过时的地震设计标准和动态分析方法，因此无法了解那些老坝的地震安全性。因此，需要基于当前最新做法，重新评估已建坝的地震安全性，并改造有缺陷的大坝。通常建议对大坝进行特定场地的地震危险性分析。当前的大坝以及用于控制强震后水库安全的设施必须能承受安全评估地震的地面运动。地震动参数可以利用概率或确定性地震危险性分析确定。强震作用下，大坝可能发生非弹性变形，因此需要在时域内进行地震分析。此外，地震对大坝造成的危害包括地面震动、断层移动、块体移动等。工程师所需的地面运动并非实际的地震地面运动，而是地面运动模型，用以进行大坝的抗震安全设计。同时必须牢记，在大坝较长的生命周期内，需要进行多次大坝安全评估。
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