Nonlinear dynamic analysis of power plant air-cooled condenser (ACC) structures: An industrial application of OpenSees software

The Air-Cooled Condenser (ACC) structure is one of the pivotal industrial buildings in Combined-Cycled Power Plants. This structure functions as a condenser of water steam, which is conveyed to it through the steam turbine generators, and accumulates the produced water and returns it to the plant’s main water circulation system. While the overall behavior of ACCs under earthquake is fairly known, important details such as the seismic response modification coefficient, R, have been a matter of controversy among the involved engineers. To address these ambiguities and in order to conduct a sure design, a more precise investigation of seismic behavior and response of these structures was deemed to be in demand. Answering this want, a numerical program was created in OpenSees numerical modeling platform to generate models for ACCs of different types, dimensions, and mechanical properties. The numerical results obtained from the analysis, especially for concrete ACCs, for whom investigation of their behaviour was thought to be more necessary, accorded well with the expected seismic behaviour foreseen for these buildings.