Study On Earthquake Action Effect Of High And Low Bays Columns Of Main Powerhouse In Thermal Power Plant Considering Higher Modes

Earthquake is still the main reason caused destruction and collapse of the mainpowerhouse in thermal power plant, so it is particularly important to study theanti-seismic performance of the main powerhouse in thermal power plant, especially inhigh degree district where the earthquake is occurred frequently. But for mainpowerhouse in thermal power plant of large capacity unit, the traditional mainpowerhouse of reinforced concrete structural system can not meet the requirements ofdesign. Our study group study the main powerhouse structure system, propose the fewwalls SRC frame-bent structure system, and study the anti-seismic performance. DoctorBai believes the new structure system can be good to meet the requirements of largecapacity unit main powerhouse in thermal power plant and obtains some constructiveconclusions. But there is little research about this new structure system on the mainpowerhouse considering higher modes, the damage of higher building higher thanexpected in the Kobe earthquake and Chi-Chi earthquake indicates the effect of highermodes can be not neglected. So it is essential to study the effect of higher modes on thenew structure system.In this paper, taking the few walls SRC main powerhouse in thermal power plantwith1000MW units in8degrees area as the research object, adopt the method ofexperiment research and SAP2000finite element software analysis to study the dynamiccharacteristics of structure, examine the modal participating mass ratios through modalanalysis, and get the reasonable number of modes shapes. Because the effect of highermodes for bottom shear of middle columns of high and low bays in main powerhouse is more obviously, so it is needful to adjust the columns bottom shear calculated throughmodal response spectrum method. The adjustment method is that compare the columnsbottom shear calculated through modal response spectrum method between considering10modes and considering200modes. Calculate the shear increase coefficient to adjustthe columns bottom shear to ensure adequate safety reserves. Study the effect of highermodes on the layers displacement of main powerhouse. Calculate shear increasecoefficient under different site category through above method and analyze the effect ofsite category on shear increase coefficient. Then according to damage of mainpowerhouse structure, summarize the question needed taking attention of design ofmain powerhouse, and study the main structure measure of main powerhouse.