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題 名 | Cracking Damage Assessment of Reinforced Concrete Members=鋼筋混凝土構材之開裂損傷評估研究 |
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作 者 | 陳文雄; | 書刊名 | Proceedings of the National Science Council : Part A, Physical Science and Engineering |
卷 期 | 22:6 1998.11[民87.11] |
頁 次 | 頁765-774 |
分類號 | 440.328 |
關鍵詞 | 鋼筋混凝土構材; 開裂損傷; Crack; Damage; Concrete cover; Corrosion; |
語 文 | 英文(English) |
中文摘要 | 混凝土中之鋼筋腐�蚻O鋼筋混凝土結構物損傷主要原因之一,本文為建立一個有 關混凝土結構物之維護管理、損傷評估、補強及評鑑系統,對混凝土構件之開裂,鋼筋腐蝕 問題加以研究。考慮因子為混凝土強度、鋼筋應力、鋼筋直徑、保護層厚度四種,使用 108 支高強度混凝土及 108 支普通強度混凝土試體之實驗結果, 探討各因子對承載下混凝土表 面裂縫寬度 W �搕怷�筋表面混凝土保護層剝離長度 W �腹A解載後混凝土表面餘留裂寬廣 W 之期關關係。研究結果顯示,W �虞|隨保護層厚度及鋼筋應力之增加而增大,此趨勢對混 凝土開裂和鋼筋之腐蝕問題有很重要之啟示,即保護層厚度之增加會加大鋼筋暴露腐蝕性物 質之機率。 高強度混凝土和普通強度混凝土對上述行為之相異性,研究結果顯示在相同條件下高強 度混凝土產生較小之W �搕庛�大之W �葉�。高強度混凝土之裂縫控制,現行 ACI Code 公式 檢驗則還可以適用,但其餘裕比普通混凝土小。如考慮裂縫內部剝離之行為則有不保守的趨 勢。 |
英文摘要 | In order to develop an integrated scheme for general damage assessment and to comprehensively study the strengthening of damaged reinforced concrete members, cracking problems in reinforced concrete members were studied. Tests on 108 high strength concrete specimens and 108 normal strength concrete specimens are discussed. The main variables are the clear concrete cover thickness, D�a, bar diameter, D�k, concrete strength, f��', and level of steel stress, f��. The cleavage behavior between the concrete cover and the bar surface and the length of separation, W��, at the interface between the reinforcing bar and concrete cover under loading are studied. The crack width on the concrete suface under loading, W��, and unloading, W , were measured. The typical relationship is obtained between W or W�廇nd W��, as a function of D�a, D�k, f��' and f��. This research reveals that W�綑ncreases with increasing D�aand increasing f��; thus, exposure of the reinforced steel to aggressive substances may increase with increasing concrete cover thickness. Comparison of the crack widths is made between the high strength concrete and normal strength concrete. It is found that W�慉or the high strength concrete is somewhat smaller than the W�慉or the normal concrete, but that W�粵or the high strength concrete is larger than that for the normal strength concrete. The ACI equation predicts the crack width of a high strength concrete well, but with a safety margin which is smaller than that obtained for the normal strength concrete. However, high strength concrete is not so likely to resist steel corrosion from the standpoint of the internal shape of the crack. |
本系統中英文摘要資訊取自各篇刊載內容。