A simplified model for seismic analysis of a 1 000 MW tower type lignite boiler steel structure was studied,in which the mass of boiler is added to main steel structure replacing its seismic action. The seismic behavior differences among the simplified model and two models with boiler are studied. One of the two models with boiler used steel bars to inhibit sway of boiler. All of the models remain elastic under small earthquake actions,and the stress responses are the largest in simplified model. Under stro...