ریسک لرزه ای و تحلیل ساختاری سد بتونی (سد قوانین رودخانه گوادالفیو)

The aim of this paper is to describe the seismic hazard performance on the site of Rules Dam, in Granada province (southern Spain), and the seismic influence on this body’s dam, as well as on its critical elements, the reservoir and the interaction fluid-structure. The seismic hazard defines the Deterministic Seismic Hazard Assessment (DSHA) and the Probabilistic Seismic Hazard Assessment (PSHA), which are important to calculate the Safety Evaluation Earthquake (SEE) and the Operating Basis Earthquake (OBE), respectively. This recent seismogenic zone provides important data to do the analysis, such as regional geologic setting, seismic history and seismology. In the Spanish code the Peak Ground Acceleration (PGA) for this area is 0.17 g, however in the current analysis the greatest soil acceleration registered is 0.35 g, which is about twice the value. Three accelerograms (controlling earthquakes), by using the Engineering Strong-Motion database, have been chosen to identify the seism’s main characteristics. The dam analysis using different software needs to be done to calculate the vibration periods, the hydrodynamic pressure and the maximal vertical stresses. Time-history analyses have been made to analyze the consequences of a dam failure and to estimate minor damage acceptance. The analyses show that the stresses exceed the tensile maximum allowed creating plastic hinges. There are other factors which can affect the dam’s behavior such as the vertical component of the earthquake and the silt in the reservoir bottom. The concrete arch gravity dam needs to be modeled in two- and three-dimensions, in accordance to classic theoretical method and current codes, considering its big dimensions (length of the crest: 620 m; radius: 500 m; area of the reservoir whit a operating level: 308 Ha). A dam is an extremely strategic work which needs to be carefully designed to avoid environmental damage to water reservoirs and nearby facilities and for human security. Given that the recent sources of hazard in Spain are from 2015, it would be advisable to reassess the seismic hazard particularly related to existing dams of category A (Spanish code) in areas of high seismicity.