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碩士論文公告區 |
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| 年度： | 91 | |
| 姓名： | 王弘義(Hung-Yi Wang) | |
| 論文題目(中)： | 基樁應力波非破壞檢測技術之比較評估 | |
| 論文題目(英)： | Comparison and Evaluation of Stress Wave Non-Destructive Testing Technigues on Piles | |
| 摘要(中)： | ||
| 橋樑在整個交通運輸系統中佔有很重要的地位。大多數的橋樑基礎是直接座落在河面或是埋置於地面下方，這些基礎受到河水沖刷、地震反覆震動及土石流的衝擊等外力作用，則會造成其所含基樁損壞而導致橋樑安全性降低，如果能發展出一套有效的方法來評估現地橋樑基樁的完整性，對於評估整座橋樑的安全性將有更實質的幫助。 本論文之目的在探討目前常用之應力波非破壞檢測（Nondestructive test NDT）技術對不同缺陷之檢測能力。利用自行灌鑄之模型基樁，在其內部預先佈置大小、形狀不同之缺陷，並使用大小不同之敲擊錘，及改變錘頭之材質，比較音波回音法（Sonic Echo, SE）、脈衝反應法（Impulse Response, IR）及超震測法（Ultra seismic, US）等各種檢測技術對這些預設缺陷之偵測能力，期能找出最佳之基樁缺陷非破壞檢測方法。 對各模型基樁進行檢測後可以獲得以下結論，導入基樁內之應力波波長大小，主要是敲擊鎚與基樁接觸時間長短有關，接觸時間長則導入基樁內之波長長，故在樁內傳遞主要為實體波，接觸時間過短者，由於表面波所佔比例變大，反而增加訊號辨識之困難度；基樁所含缺陷較細微者，因缺陷處反射訊號較弱，需要謹慎細心方能找出缺陷位置。將時間域與頻率域之訊號一起判讀，則可以準確判斷基樁之完整性。 |
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| 摘要(英)： | ||
| Bridges play an important role in the transportation system. Most of the bridge piles are beneath the water table or buried underground. All the actions from scouring, vibrating and debris flow, will result in the piles damaged and lower the safe operations of the bridges. If one could find a well defined method to evaluate them, it will be useful to distinguish the safe operation of bridges. The main objective of this research is to investigate the feasibility of applying non-destructive testing techniques in detecting the integrity of piles. Model piles with artificial detects were constructed and tested with various sizes and different tips of hammers. Different NDT technigues such as Sonic Echo, Impulse Response, and Ultra Seismic in detecting those defects were evaluated . Results of this study indicate that the detectability of defects depends on the significant wave length induced by the impact. If a short wave length is used, the signal from surface wave will offset the signal from body wave thus cause difficulity in judging the longitudinal wave from. It is concluded that the capability of detecting defects in pile can be improved by using both time domain and frequency domain signals. |
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| 檔案： | 沒有相關檔案 | |
| 相關連結： | http://ethesys.lib.cyut.edu.tw/ETD-db/ETD-search-c/view_etd?URN=etd-0729103-025526 | |