Analysis Of Natural Vibration Characteristics And Seismic Response Of Xi Luodu High Arch Dam During Construction Period

The construction period and the initial period of impoundment are frequent occurrence periods of dam accidents.During the construction phase,due to the shape of the dam’s structure,the nature of the construction materials,and the loads that it bears,etc.,they change with time,and during the construction period.Compared with its high failure probability and high risk,it directly affects the safety of the engineering structure.In addition,during the construction period,the water level,pouring height and sealing arch height will also change with time,which directly affects the deformation and stress of the dam during operation.This article takes Xi Luodu as the engineering background,combines the influence of the impoundment level,the pouring elevation,and the pouring of the jumper during the construction period of the dam.It is committed to accurately grasping the dam’s working performance during the construction period.The following aspects are mainly analyzed by the study.Firstly,in the aspect of statics,the impact of the impoundment process on arch dams is mainly considered from the late construction period,and the water body is simulated with potential fluids to analyze the stress and strain conditions of the dam under static load.Secondly,in terms of self-vibration characteristics,the natural vibration characteristics of the dams are calculated in the nine time periods,and the natural vibration frequencies under different pouring heights are obtained,and the later water storage process is added,and there will be water and no water conditions.Comparison of vibration frequency and selfoscillation mode;Finally,in the aspect of dynamic response,the whole pouring process is divided into two plates for calculation and analysis.One part is the process of water storage before and during the middle period of construction,and the other part is the process of early impounding of water during the later period of construction.In the no-water time period,the stress and displacement time-course responses of the dam are mainly compared and analyzed;after the water-storage period increases,after the two parts of dynamic and static forces are calculated,the principle of dynamic and static superposition is used to divide the two parts.After the results are superposed,stress and displacement time-history response analysis is performed;In conclusion,during the construction period,through comparison and analysis of the calculation results,it was found that when there are earthquakes in two time periods,the damage to the dam body is great.Attention should be paid to the construction during this period,and corresponding attention should be paid to it.The weak points of the body should have certain measures and precautions against these weak spots.