For transmission steel high tower, wind-induced vibration is significantly increased because of its high height and flexibility. Long-term vibration may damage tower and conductor. Thus, it is necessary to enhance ability of supervision the vibration and take measures to control it to allowable extent. In the paper, a method to achieve wind-induced vibration characteristics of high tower is studied using technologies of environmental incentive of wind load and wireless sensor acquisition and transmission signals. Monitoring device and sensor are designed to acquire meteorological environment parameters and tower vibratory responses. Parameters of tower vibration are analyzed and determined based on a monitoring system. The technologies are used for monitoring the wind-induced vibration of a large-span steel tubular high tower. It is demonstrated that the technologies put forward are practicable and suitable for field working condition, and present good effects.

The 500kV metallic oxide lightning arrester is a piece of porcelain electrical equipment and easy to be damaged under severe earthquake, because the equipment is made of brittle materials and can only subject to limited earthquake action. Damping devices can be mounted onto the porcelain electrical equipment to protect the equipment by absorbing large amaunt of earthquake energy. On that type of lightning arrester added with damping devices, the analyses of the seismic energy dissipation response of the equipment are carried out at diff erent levels of seismic fortification intensity using the finite element analysis program ANSYS. At the same time, a contrast analysis on the seismic responses of anti-seismic and seismic energy dissipation of the lightning arrester was conducted. The results of the analysis showed that the arrester with damping device had good damping effect and it could be referred by the practical application of engineering projects.

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Change of land-use pattern causes the change of underlying surface environment in the basin, thus influencing the source and sink of hydrological cycle in the study area and to greatly affect the groundwater level. In order to study the relationship between underlying surface change and groundwater level, this paper quantitatively analyzed the remote sensing images of the Hailiutu River basin acquired in different periods and collected long-series groundwater monitoring data, and this paper drew a groundwater level change map by calculating the transfer matrix of different land-use types. On this basis, this paper analyzed the groundwater level and influential factors for the transfer amount of different land-use types. Results showed that the change in groundwater level was mainly influenced by the underlying surface change. The land-use types exhibited strong tempo-spatial transformation. Where there was a drastic change of land-use type, there was a sharp change in groundwater level, indicating that the change of land-use type greatly influenced the underlying surface and was positively correlated with the spatial distribution of groundwater level.

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