High-voltage electrical post equipment is generally installed on steel supports,which amplifies the seismic inputs and degrades the seismic performance of equipment.This study proposed a variable cross-section damped ...High-voltage electrical post equipment is generally installed on steel supports,which amplifies the seismic inputs and degrades the seismic performance of equipment.This study proposed a variable cross-section damped steel support frame(VCDFS)with viscous dampers to reduce seismic responses of both tall and low-rise electrical equipment.The VCDFS contains a trapezoidal damper layer to generate rocking motions,enabling the diagonal viscous dampers to dissipate seismic inputs.A theoretical model of post equipment with VCDFS is established,and an optimal design procedure is proposed.The analysis shows that the remaining static stiffness ratio λ_(k) is the key parameter that determines the effectiveness of the VCDFS.The VCDFS reduces the average displacement and stress response of a post insulator by 39.4%and 44.6%,respectively,together with a significant decrease in the dynamic amplification factor.Therefore,it is recommended to use the VCDFS instead of the conventional latticed-steel frame in earthquake zones.展开更多
A dynamic calculation model of frame supporting structures with prestressed anchors for the slope stability is proposed.The frame and soil are closely contacted in the role of prestressed anchors and they cannot be se...A dynamic calculation model of frame supporting structures with prestressed anchors for the slope stability is proposed.The frame and soil are closely contacted in the role of prestressed anchors and they cannot be separated along the whole slope.The lateral displacement of frame and soil is nearly in phase.The movement characteristic satisfies the theory of elastic foundation beam.The frame is treated with elastic foundation beam in this model.The influence of prestressed anchors is simplified as linear spring and damped system related with velocity.Under the condition of horizontal earthquake excitation,the equation of vibration response is established by using the model of dynamic Winkler beam and the analytical solutions are obtained for simple harmonic vibration.This method is applied to a case record for illustration of its capability,in order to verify the method,3D nonlinear FEM(ADINA)is used to analyze the seismic performance of this case,the comparative results show that the design and the analysis are safe and credible by using the proposed method.The calculation model provides a new way for earthquake analysis and seismic design of slope stability supported by frame structure with prestressed anchors.展开更多
基金Guangdong Basic and Applied Basic Research Foundation under Grant Nos.2022A1515110561 and 2023A1515010072Natural Science Foundation of China under Grant Nos.52308488 and 52378499。
文摘High-voltage electrical post equipment is generally installed on steel supports,which amplifies the seismic inputs and degrades the seismic performance of equipment.This study proposed a variable cross-section damped steel support frame(VCDFS)with viscous dampers to reduce seismic responses of both tall and low-rise electrical equipment.The VCDFS contains a trapezoidal damper layer to generate rocking motions,enabling the diagonal viscous dampers to dissipate seismic inputs.A theoretical model of post equipment with VCDFS is established,and an optimal design procedure is proposed.The analysis shows that the remaining static stiffness ratio λ_(k) is the key parameter that determines the effectiveness of the VCDFS.The VCDFS reduces the average displacement and stress response of a post insulator by 39.4%and 44.6%,respectively,together with a significant decrease in the dynamic amplification factor.Therefore,it is recommended to use the VCDFS instead of the conventional latticed-steel frame in earthquake zones.
基金supported by the National Natural Science Foundation of China(Grant No.50978129)the Gansu Provincial Science and Technology Foundation of China(Grant No.2GS064-A52-040)Scientific-research Development Foundation of Lanzhou University of Technology(Grant No.BS04200901)
文摘A dynamic calculation model of frame supporting structures with prestressed anchors for the slope stability is proposed.The frame and soil are closely contacted in the role of prestressed anchors and they cannot be separated along the whole slope.The lateral displacement of frame and soil is nearly in phase.The movement characteristic satisfies the theory of elastic foundation beam.The frame is treated with elastic foundation beam in this model.The influence of prestressed anchors is simplified as linear spring and damped system related with velocity.Under the condition of horizontal earthquake excitation,the equation of vibration response is established by using the model of dynamic Winkler beam and the analytical solutions are obtained for simple harmonic vibration.This method is applied to a case record for illustration of its capability,in order to verify the method,3D nonlinear FEM(ADINA)is used to analyze the seismic performance of this case,the comparative results show that the design and the analysis are safe and credible by using the proposed method.The calculation model provides a new way for earthquake analysis and seismic design of slope stability supported by frame structure with prestressed anchors.
