大尺寸鋼筋(D43、D57)與混凝土握裹行為分析

Bond Behavior Analysis of Large-size Steel Bars in Concrete

吳泓叡(Hung-Ruei Wu)

指導教授 ： 干裕成

朝陽科技大學/理工學院/營建工程系/碩士(2011年)

摘要

本研究透過鋼筋握裹試驗，探討混凝土與各號尺寸鋼筋間之握裹力學行為；並對有裂縫產生之混凝土與鋼筋間之力學行為進行研析。本研究試驗成果，有助於補充現行鋼筋混凝土規範之不足；同時，試驗中加入音射監測，可提供相關非破壞檢測及監測評估技術之準確性。
本研究試驗發現，相同混凝土強度中，鋼筋直徑越大，初裂握裹強度及極限握裹強度愈小；且二次尖峰載重P2u與極限載重Pu，亦隨著直徑大致呈線性增加；在相同鋼筋號數中，混凝土的強度越高，初裂握裹承載力與極限握裹承載力皆隨著混凝土強度增加而增加，但鋼筋的握裹初裂強度與極限握裹強度卻隨著鋼筋直徑增加而降低；除此，全開裂之試體，殘餘強度隨著鋼筋直徑增大而增加，大致上全開裂殘餘強度(不計鋼筋號數)約有65%-88%。

關鍵字

拉拔試驗 ； 鋼筋尺寸 ； 音射法

並列摘要

This research attempts to investigate the bond behavior between concrete and rebar in various sizes through the pull-out test. The bond behavior of concrete with a crack along the rebar is also studied. Acoustic emission (AE) was employed to monitor the crack of concrete during the load test. The test results reveal that for a given concrete strength, larger rebar performs lower initial crack load and ultimate bond strength. In addition, ultimate load capacity and secondary peak load increase with the rebar size. For the same rebar size, both of the loads at initial crack and ultimate load increase with the increase of concrete strength; while both the stresses of rebar at initial crack and ultimate load stage decrease with the increase of rebar size. The residual strength of those concrete pre-cracked along the rebar turns out increasing along the rebar size. It ranges from 65 % to 88 % of the fully bond strength regardless of the rebar size.

並列關鍵字

Acoustic emission ； Rebar size ； Pull-out

參考文獻

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