[[alternative]]Seismic Analysis of Transmission Towers Considering Slope Stability

[[abstract]]發電廠於傳輸電力至不同住宅或工商業區之過程中，相關傳輸路線常須因應地形及地貌之變化而呈現俯仰轉折之多變走勢，而台灣地區位處於環太平洋地震帶上，故構造物之抗震能力原本即為結構設計上之首要考量，復加以本島境內山巒綿亙、丘陵起伏，致眾多高壓輸電塔常須建造於邊坡毗鄰之處；使得輸電塔構造在強震作用下之安全性將與邊坡之穩定息息相關。本文一方面建立有效之結構分析模式，精確模擬輸電塔之受震行為，並獲得各元件之幾何非線性動力行為，另則縝密探討不同地質與地形條件之邊坡，於地震力及電塔慣性力共同作用下之安全度分析以及潛在滑動之破壞情形；冀期在建立包含輸電塔及邊坡兩子系統之三維全域系統之後，輸電塔之震力分析將可進ㄧ步獲致更佳之可靠性與實用性，研究結果顯示，輸電塔於邊坡上之興建位置及土壤之強度參數將與結構安全與否息息相關。[[abstract]]In the course of electricity conveyance beginning from power plant to some residential and industrial areas, the conveying route is often changeable both in its elevation and its orientation, due to the uneven topography or terrain which the transmission towers march across. Taiwan being situated in the vicinity of boundary zone between the Eurasian plate and the Philippine Sea plate, the ability in earthquake resistance is hence undoubtedly one of the essential requirements in structural design. On the other hand, plenty of mounds and mountains are found to extend uninterruptedly in Taiwan which makes many transmission towers here are inevitable to be built nearby the slope. As a consequence, the safety of these towers under strong ground motion would be closely related to the stability of slopes concerned. In this research, the effective analytical model of transmission towers will be established such that the precise dynamic behaviors, including both geometric and material nonlinearities, of tower members can be found. In addition, the detailed investigation on the potential sliding of the slopes with various patterns and under the combined action caused by seismic force and the inertia force from the tower will be undertaken. It is expected that through the establishment of the global 3-D system composed of both tower- and slope-subsystems, the better reliability and applicability for the analytical outcome will be accomplished. It is shown in the results that the structural safety for transmission towers will closely depend upon the spots where the tower is located at and upon the magnitudes of the strength parameters of soil concerned.[[sponsorship]]中華民國力學學會[[conferencetype]]國內[[conferencedate]]20061215~20061216[[conferencelocation]]臺北市, 臺灣[[countrycodes]]TW