نوع مقاله : علمی - پژوهشی
نویسندگان
1 دانشجوی دکتری-گروه مهندسی عمران- دانشکده فنی مهندسی- دانشگاه آزاد اسلامی ، واحد زنجان - زنجان-ایران
2 دانشیار-گروه مهندسی عمران- دانشکده فنی و مهندسی- دانشگاه زنجان- زنجان- ایران
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
In this study, the linear and nonlinear seismic behavior of the Koyna dam has been investigated for the condition of the dam with unsaturated concrete and the dam with a combination of saturated and unsaturated environment. For this purpose, using Abaqus software the boundary line between the saturated and unsaturated environment has been determined. In the following, various parameters of saturated concrete have been evaluated. Finally, linear and nonlinear analyzes have been performed under the effect of the Koyna earthquake. To model the nonlinear behavior of concrete, the CDP behavior model has been used. The results show that the saturation of the dam has reduced the maximum values of displacements in linear and non-linear mode. In the linear analysis, the amount of reduction of the maximum horizontal displacement in the saturated state compared to the unsaturated state for the reservoir up to the height level of 36, 66.5 and 103 meters is equal to 17.34%, 24.00% and 17.30%, respectively. Also, in the non-linear analysis, the reduction of the maximum horizontal displacement in the saturated state compared to the unsaturated state for the reservoir up to the height level of 36, 66.5 and 103 meters is equal to 31.58%, 30.72% and 22.38%, respectively. For the condition of the dam with a saturation elevation lower than the downstream slope change elevation, the maximum values of the first and third principal stresses in the linear analysis and the amount of damage in the nonlinear analysis have decreased. For a case of the full reservoir where the downstream slope change is saturated, the amount of cracking in the entire structure has decreased, but it has increased in the downstream and upstream slope change location. Finally, Results show that it is necessary to evaluate the behavior of the dam with saturated and unsaturated environment simultaneously.
کلیدواژه‌ها [English]
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