The effect of roof systems on seismic performance of reinforced concrete frame-bent main building of large-scale thermal power plant

Abstract

The roof systems of turbine hall in large-scale thermal power plant are often simulated by approximate rigid beam model. Wenchuan earthquake again revealed the frequent destruction of these roof systems. In this study, three kinds of general roof systems as space grid, trapezoid steel roof truss and reinforced concrete (RC) mansard roof truss were considered. Also, the numerical model of RC frame-bent main building in large-scale thermal power plant was established. Seismic performance of main building was compared with approximate rigid beam model, and the damage mechanism of roof systems was also investigated. The results indicate that the response calculation of frame part by rigid beam model is feasible, and roof systems give most contribution to the response of bent part. After considering roof systems, overall collaborative performance is enhanced, but bent part is still unable to become a second defence part after shear walls fail. The torsional irregularity of roof systems is very serious, and more attentions should be paid to the bearing shear failure of space grid and components strength failure of RC roof systems.