Abstract: Safety monitoring index is important for monitoring dam safety. In the analysis of displacement deformation of concrete dam by FEM, we determined the first, second and third level monitoring indexes of the dam’s horizontal displacement by employing strength reserve method. The monitoring indexes determined by the method takes the various water level loads into consideration, therefore is more rational than monitoring indexes by conventional methods. This research provides an effective basis for the comprehensive evaluation and decision of the dam operation conditions.

Key words: monitoring index, strength reserve method, horizontal displacement, concrete dam