| Electric power constructions have important influences on development of national economy, especially in earthquake relief. The main building in thermal power plant is one of the key electric power constructions, and from the first thermal power plant in the world was born in 1875, the main building structural style has experienced many changes in more than 130 years. In recent years, many larger thermal power plants have built up following development of national economy and power units capacity. The main buildings are important electric power construction and lifeline engineering, and they have complex mechanical performance, such as weak integrity caused by technology requirement, large loads action, mass and stiffness distributed uneven, serious earthquake action effect. China located in multiple earthquake area, considering reduce the influence of earthquake action effect and ensure the safe running of power units, it has significant theoretical and future practical value for seismic performance and design method research on the main building in thermal power plant.There are some studies express that reinforcement concrete structure just can be adopted in low intensity district, the stiffness of reinforcement concrete structure with end shear walls distribute uneven, and they have some congenital deficiencies. Although the seismic performance of steel main building is better than reinforcement concrete structure, the cost of construction and maintains is far more than reinforcement concrete structure. In the dissertation, on the basis of investigation and calculate analysis about many kinds of main building structure systems, few walls and SRC frame new structure main building which can satisfy seismic and technological arranged requirements is proposed to adopt in large thermal power plant. Then model experiment and nonlinear infinite analysis of the new structure main building is carried out to study seismic performance, seismic design method is submitted. With traditional Chinese medicine theory the whole-life design method of main building is proposed.Firstly, a 1/7 scale space model of three spans and three frames which are from few walls and SRC frame main building were designed and build to carry out the dynamic character test, pseudo-dynamic test and pseudo-static test. Based on the test, the dynamic characters of model including the natural vibration frequencies, mode shapes, and damping ratio, the load and displacement response on earthquake waves action with different peak accelerations are acquired.Secondly, the experiment results are carefully analyzed, dynamic characters, the rule of stiffness degradation, the capacity of whole deformation and energy dissipation, the ductility, bearing capacity of few walls and SRC frame structure are studied. The weak story is determined, and the mechanical performance of classic members which contain horizontal shear walls, coalbunker beams, deaerator beams, ultra short columns are discussed.Thirdly, the finite element model of few walls and SRC frame structure is built up using ABAQUS. By using ELCENTRO wave as earthquake input, the nonlinear seismic response of the new structure is analyzed. The mechanical performance, deformation and load-bearing capacity of the new structure with 8 intensity intermediate and rare earthquake actions are studied. The results of experiment and finite element analysis indicate that the few walls and SRC frame main building can meet the satisfaction of 8 intensity fortification requirement which is, so called,' no damage in small earthquake, no collapse in strong earthquake'. The new structure has good deformation and energy dissipation capacity, and the weak story is located on running floor. The horizontal shear walls can perform as the first seismic defending line of the structure.Fourthly, considering the safety of the main building structure and keeping the operation of the technological equipments, the general seismic performance fortification targets put forward, and the seismic design procedure of the few walls and SRC frame are presented. Both the method of earthquake force calculation and the deformation control are discussed. In order to maintain the collapse resistant capacity of the structure, the multiple seismic defending lines are studied. And the results indicate that the shear walls with good seismic performance are the first seismic defending line of the few walls and SRC frame main building. The arrangement principle and the edge constraint member design method of shear walls are studied. The limit of axial compression ratio and appropriate steel ratio of SRC (steel reinforcement concrete) columns are established. Combining with the results of the test and the analysis, a reasonable design suggestion and seismic construction details of few walls and SRC frame structure are presented. Fifthly, the thought of' the organic whole concept' and'treatment based on syndrome differentiation' which is based on theoretical system of traditional Chinese medicine is introduced into the main building structure whole life design. The whole life of main building is divided into three stages, and the design processes of each stage are established. Considering the performance variation law of main building structure in its whole life, the optimal design formula for whole life cost of main building is summarized, the purpose of which is to achieve maximum economy and social benefit with minimum total investment.Finally, according research contents of the whole dissertation, some important conclusions about seismic performance of few walls and SRC frame, such as mechanical properties of classical members, design methods, whole life design procedure are summarized. At present, the seismic performance research about the few walls and SRC frame structure is the first time in the domestic. The study of this dissertation can provide basic data and references for further practical engineering application of the few walls and SRC frame main building structure.
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