| Electricity is the cornerstone of scientific and technological progress and an important guarantee for national economic development.As the carrier of power transmission and distribution,transmission lines are an indispensable part of the electric system,and its importance is self-evident.With the growth of the new round of technological driving force and continued economic development,the country has put forward the policy of vigorously developing "new infrastructure",and the construction of UHV transmission lines is the highlight and plays a leading role.China has a vast territory and complex terrain conditions,and electric systems inevitably traverse through earthquake-prone areas.According to previous statistics on strong earthquake disasters at home and abroad,it is not uncommon for member bars to be damaged or even collapse,causing enormous economic loss.In addition,existing studies have investigated that large-span structures such as bridges,underground pipelines and dams are prone to more violent seismic responses when they cross active faults.However,at present,there are few available knowledges for fault crossing transmission tower-line systems.Therefore,investigating the seismic response of the ultra-high voltage transmission tower-line system crossing the fault repture is of great significance.In this paper,cross-fault ground motions were simulated and generated,and the method of numerical simulation was used to investigate the law of seismic response and collapse failure mode of the fault crossing UHV transmission tower-line system,and the effects of fault crossing angles,fault crossing locations,and traveling wave effect on the structures are studied in detail.The main research contents are as follows:(1)Based on the equivalent velocity pulse model,the superposition of natural far-field high-frequency seismic waves and artificial low-frequency velocity pulses was used to generate cross-fault ground motions including forward directivity effects and fling-step effects,and the accuracy was verified;(2)Based on the dynamic display analysis method,this paper investigated the laws of seismic responses and collapse failure modes of a transmission to wer-line system at different crossing fault angles and crossing fault locations utilizing ABAQUS finite element software,and summarized the optimized crossing fault angle and the optimized crossing fault position;(3)By changing the fault crossing location,the effects of the traveling wave effect of ground motion on the structural dynamic response and collapse failure of the cross-fault transmission tower-line system in the case of mid-span and side-span cross-faults were studied respectively.It provides a reference for the seismic design of the UHV transmission tower-line system across faults. |
