鄭富書臺灣大學:土木工程學研究所王少韡Wang, Shao-WeiShao-WeiWang2010-07-012018-07-092010-07-012018-07-092009U0001-1808200910083100http://ntur.lib.ntu.edu.tw//handle/246246/187917岩石邊坡與土壤邊坡最大的差異在於岩石邊坡發生破壞往往沿著弱面破壞,此種有主要滑動面之邊坡破壞的行為,於1965年Newmark提出了滑動塊體法,為這類邊坡穩定性分析注入了新的分析方式。 在滑動塊體法中,提出了臨界加速度的觀點,當可能滑動之塊體所受的地震加速度超過其所能承受之臨界加速度時,塊體便會滑動產生永久位移。此方法假設塊體之臨界加速度為一定值,滑動面間的摩擦行為造成之影響暫不考慮,且臨界加速度係以靜態力平衡的狀態下得到。在前人的研究中,透過尖峰摩擦角所定義的臨界加速度,計算得到之累積位移量會有低估的現象,而以殘餘摩擦角定義之臨界加速度則是會有高估現象,因此也有學者提出了臨界加速度衰減的概念或塊體滑動後即採用殘餘摩擦角進行計算。 因此本研究便是基於滑動塊體法的基本概念,利用模擬岩塊於小型震動台進行一系列之實驗,首先探討震動條件下,塊體滑動時的即時靜摩擦角 是否與靜態條件所得到之靜摩擦角 相同,更進一步的探討受震滑動歷程中滑動面間的摩擦行為,並且探討震動頻率、滑動塊體正向應力及材料特性對即時靜摩擦角 、滑動歷程之摩擦行為的影響。 本研究中發現震動頻率及正向應力皆會對震動條件下,塊體的即時靜摩擦角 造成影響,當基盤的震動頻率提高,塊體的即時靜摩擦角 會有提高的趨勢;塊體的正向應力增加時,反而塊體的即時靜摩擦角 會有降低之趨勢。Different from soil slope, the failure of rock slope destroyed along weak plane. Accordantly, block sliding method for these slope stable analysis was be devised by Newmark in 1965. A new point “critical acceleration” was devised in block sliding method; when block acceleration induced by earthquake exceed the “critical acceleration” of the sliding interface, the permanent displacement of sliding block was happened. However, in the method, “critical acceleration” derived from static force equilibrium was assumed to be a constant. The “critical acceleration” determined by peak friction angle could resulted the underestimate of permanent block sliding displacement; the “critical acceleration” determined by residual friction angle could resulted the overestimate of permanent displacement. Base on block sliding method, in this study, there were series experiments by using shake table. At first, to compare the instantaneous static friction angle of block obtained from shake table experiment and static friction angle obtained from tilt test, and then to investigate the influence of block frictional behavior by following factor: frequency of base vibration, normal stress of block, material of block. In this study, the instantaneous static friction angle of block was affected by frequency of base vibration and normal stress of block under dynamic shaking condition. When the frequency of base vibration was higher, the instantaneous static friction angle of block was higher; the instantaneous static friction angle of block reduced when the normal stress of block increased.口試委員審定書 I謝 II要 IIIbstract IV錄 V目錄 VIII目錄 IX一章 緒論 1.1研究動機 1.2研究目的 1.3研究方法 2.4研究內容 3二章 文獻回顧 5.1 傳統斜坡岩塊受震分析方法 5.2 塊體受震滑動之動態分析 5.3 摩擦行為探討 9.4 研究相關名詞定義 10三章 研究方法 20.1模擬岩塊之選取 20.1.1 模擬岩塊之材料相似律 20.1.2 模擬岩塊之材料選擇 21.1.3 模擬岩塊之基本力學性質 22.1.4 模擬岩塊相似律分析 22.2儀器介紹 22.2.1 傾斜台 22.2.2 試體承載基座 22.2.3 小型震動台 (small scale shake table) 23.2.4 雷射位移計 (laser displacement meter) 23.2.5 單壓試驗壓力機 23.3實驗方法 23.3.1靜摩擦角量測 23.3.2 動摩擦角量測 24.3.3 動態即時摩擦係數量測 24四章 震動條件下模擬岩塊即時靜摩擦角探討 35.1靜態條件下模擬岩塊之摩擦角 35.2震動條件下即時靜摩擦角之理論推導 37.3基盤震動頻率對即時靜摩擦角之影響 38.4正向應力對即時靜摩擦角之影響 40.5模擬岩塊材料配比對即時靜摩擦角之影響 42.5.1 水灰比不同之模擬岩塊與即時靜摩擦角之影響 42.5.2細骨材不同之模擬岩塊與即時靜摩擦角之影響 43五章 震動條件下模擬岩塊滑動界面之靜、動摩擦行為 56.1 動摩擦角變化之量測 56.2模擬岩塊之即時動摩擦角理論公式 57.3 基盤震動頻率對即時動摩擦係數之影響 58.3.1 基盤震動頻率4Hz 58.3.2 基盤震動頻率6Hz 61.4摩擦模式之探討 63六章 結論與建議 78.1結論 78.2建議 79考文獻 80錄A 擷取速率與微分法 83錄B 垂直向位移檢核 87錄C 論文口試-問題與回覆 935112196 bytesapplication/pdfen-USNewmark震動台臨界加速度摩擦行為shake tablecritical accelerationfrictional behaviortilt test模擬岩塊受震滑動之動態摩擦行為初探A preliminary study on the dynamic friction behavior of concrete sliding under external excitationthesishttp://ntur.lib.ntu.edu.tw/bitstream/246246/187917/1/ntu-98-R96521104-1.pdf