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The offshore wind turbine tower, which has been in the marine corrosive environment for a long time, often buckles and collapses under the earthquake records. In order to study the influence of marine corrosion and CFRP reinforcement on the seismic performance of wind turbine tower structures, the horizontal displacement, horizontal acceleration and acceleration change rate of wind turbine towers are studied through numerical simulation and shaking table tests. The results show that the influence of earthquake type on the dynamic response of the wind turbine tower is different. The response values of acceleration and displacement under far-field earthquakes are larger than those of other earthquake types. The increase in PGA has a greater impact on the structural response range in the near-field earthquake. Corrosion defects not only increase the sensitivity of the wind turbine tower structure to seismic response but also have different effects on the location and development of structural plastic hinges. For the structure without corrosion defects, the plastic hinge appears at the connection between the tower and the foundation, while in the corrosion structure, the plastic hinge appears in the corrosion area. Corrosion defects increase the nonlinear development of structures, especially under far-field earthquakes. CFRP reinforcement can effectively reduce the displacement effect of the top of the structure and enhance the seismic performance of the corroded wind turbine tower.

Absorber feed tank (AFT tower) is a kind of reinforced concrete structure supported steel tank. It is a composite structure used for desulfurization and cleaning in power industry. A large amount of slurry is sumped in the steel tank, and oxidation air is blown into the tank through a pipe to impact the slurry surface, then the agitator vibrates and disturbs the slurry in the tank. The structure has obvious vibration in daily operation, which is not conducive to the safety of the structure, but also brings greater psychological burden to the staff. Therefore, field monitoring and numerical simulation analysis are carried out for the AFT tower. The field investigation of AFT tower is also carried out. The video monitoring and local monitoring are used to monitor the AFT tower, and the corresponding laws of vibration are explored. A simplified simulation method for this kind of structure is proposed. The model is established with the aid of the fluid structure coupling function of ADINA finite element analysis software to study the vibration characteristics of AFT tower. The results show that the motion trajectory of AFT tower can be determined quickly by video monitoring. The local monitoring can demonstrate that the effect of mixer is the main factor of structural vibration, and the blowing in of oxidation wind intensifies the structural vibration response, resulting in different degrees of damage to the infilled wall between the columns of the structure. By comparing the numerical simulation results with the monitoring results, the reliability of the simplified model is verified, which provides a reference for analyzing the vibration response, damage mechanism and reinforcement design of this kind of structure.

Most of the old rural houses in Beijing are single-layer buildings with double-sloping roofs. Under an earthquake, the gable is prone to an outward tilt, and the structure is prone to collapse as a whole. In view of the structural characteristics of the existing rural houses in Beijing, a reinforcement technology is proposed, in which the embedded steel frame reinforcement is mainly used, supplemented by a steel plate strip reinforcement. A 1/4 masonry structure model is designed for a shaking table test. A full-scale model is established in a finite element simulation analysis. The results show that the longitudinal wall is seriously damaged, and the gable has a considerable outward inclination under earthquakes. However, owing to the reinforcement effect of the steel frame, the overall collapse of the structure is avoided. The steel strip can effectively restrain the outward inclination of the gable and ensure safety of personnel.