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碩士論文公告區 |
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| 年度： | 95 | |
| 姓名： | 楊國楨(KUO-CHEN YANG) | |
| 論文題目(中)： | 鋼結構施工銲道不正常融填之探討 | |
| 論文題目(英)： | Abnormal Welding Discovered During Work Progress | |
| 摘要(中)： | ||
| 鋼結構工程中，樑柱接頭的結合優劣，關係著整棟建物應力傳遞的確保。當鋼結構骨架的樑柱接頭採用採用銲椄型椄頭時，銲接部位因銲接材料與母材之融熔與凝結而產生了內應力、氣孔、夾渣、熱裂、冷裂等問題。 本研究主要是針對工地現場的電銲工程中，常發生的不正常融填做探討，施工現場中電銲施作人員為了增大電銲融填量，而將電銲電流加大，或填塞異物以加快融填速度，研究中模擬現場不正常融填施作之各項條件，如母材、開槽方式、融填異物材料的選定等，以手銲方式依標準程序方式製作試片，將試片分成正常融填及異物融填與加大電流融填共15片試片，藉由非破壞UT檢測及拉伸、彎曲、衝擊、化性、巨觀、微觀，6種破壞試驗之試驗數據及巨觀、微觀照片做成圖表，比較銲道正常融填與銲道不正常融填的差異性。 研究的結果顯示除了正常融填的3片試片，試驗結果皆符合各項規範要求，而不正常融填在試驗數據上，除了一片兩條銲條直接融填各項試驗符合規範外，其餘11片試片皆至少有一項以上不符合規範要求，而各項破壞試驗中以衝擊試驗的數值，最能顯現出銲道因加大電流及融填異物造成了銲道本身與母材融熔區脆化現象。試驗中證實在異物完全與銲條融熔下，非破壞UT檢測無法有效判斷出銲道是否有不正常融填行為。而如何有效規範工地現場不正常融填行為，正是現場監造人員重要的課題。 |
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| 摘要(英)： | ||
| The quality of bean-column joint is related to ensure the whole building’s stress transfer in steel structure. The welded joints will produce residual stress, blow hole , slag inclusion, hot cracking and cold cracking problems. This is caused from the fusion and solidification between welding metal and base metal when the bean-column joint of skeleton adopts welded joint s in steel structure. This research focuses on abnormal fusion of welding work in construction site. The welder tends to speed-up the welding fusion by increasing the arc current or welding foreign matter in order to increase the fusion. This paper simulates the abnormal fusion in each practical situation, such as base metal, groove type and selection of fusion foreign matters, and then adopts the standard operation process to examine test pieces by manual welding. The 15 test pieces are divided into normal fusion and increase arc current fusions. We examine them with six destructive tests includes, Nondestructive Ultrasonic Test and Tensile Test, Slide Bend Test, Impact Test, Chemical test, Metallog raphic Test and Micro-specimen Test. At the end, we record test numbers, taking macro- and micro-observation diagram to compare the normal and abnormal weldings. The research results demonstrate that all test results are in compliance with the regulations, except three normal fusion test pieces. However, there is at least one examined item not in compliance with the regulation in the eleven abnormal fusion tested pieces. The balance of the only one two-electrode tested piece meets the regulation requirements. The test figures in impact tests show the best fusion zone’s embrittement with base metal among other examining items. The tests also prove that the nondestructive UT Test cannot determine if the there is an abnormal fusion under the condition of foreign matter and electrode fuse. Thus, it is an important issue for the supervisors to effectively manage the abnormal fusion in construction sites. |
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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-0111107-041052 | |