- 摘 要
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(上海市建筑科學研究院有限公司 上海市工程結構安全重點實驗室, 上海 200032)
摘要: 設計制作了 9 組共 78 個螺旋箍筋約束高強鋼筋漿錨搭接試件,通過單向拉拔試驗,研究了其破壞機理以及鋼筋強度、混凝土強度、鋼筋搭接長度、螺旋箍筋形式等因素對搭接性能的影響. 結果表明:未配置螺旋箍筋的漿錨搭接試件主要破壞模式為混凝土的錨固失效開裂,且其承載力和強屈比隨鋼筋搭接長度的增加逐漸增加;配置螺旋箍筋后,鋼筋搭接長度大于 0. 80lab(lab 為鋼筋基本錨固長度)時,試件主要破壞模式為鋼筋受拉屈服且其極限承載力較穩(wěn)定;鋼筋搭接長度為 0. 56lab 時,試件端部混凝土出現(xiàn)開裂,部分試件的極限承載力顯著降低. 建議實際工程中鋼筋直徑為 16mm 時,螺旋箍筋約束高強鋼筋漿錨搭接的搭接長度取 0. 80lab ;其他直徑鋼筋可參考該搭接長度并經(jīng)過試驗驗證后應用.
關鍵詞: 高強鋼筋; 漿錨搭接; 螺旋箍筋; 搭接長度; 單向拉伸
中圖分類號:TU375 文獻標志碼:A 文章編號:1002-848X(2023)08-0119-06
DOI:10. 19701 / j. jzjg. LS202045
Uniaxial tension experimental study on the grouting-anchoring overlap-joint of high strength steel bar restrained by spiral stirrups
WANG Zhuolin, LI Xiangmin, TIAN Kun, WANG Mingqian
(Shanghai Key Laboratory of Engineering Structure Safety, Shanghai Research Institute of Building Sciences Co. ,Ltd. , Shanghai 200032, China)
Abstract: Nine groups of seventy-eight specimens of grouting-anchoring overlap-joint of high strength steel bar restrained byspiral stirrups were designed and fabricated. The failure mechanism and the influence of steel bar strength, concretestrength, lapping length of steel bars and spiral stirrup type on the lapping property were investigate by uniaxial tensiontests. The results show that the main failure mode of the specimens without spiral stirrups was the anchorage failure andcracking of concrete, and the bearing capacity and ductility ratio increase with the increase of lapping length of steel bars.The main failure mode of specimens restrained by spiral stirrups is steel bar tensile yield, when the lapping length is over0. 80lab(labis the basic anchorage length of the steel bar), and the bearing capacity of restrained specimens is very stable.When the lapping length of steel bars is 0. 56lab , concrete crackes at the end of the restrained specimens, and the bearingcapacity of some specimens decrease significantly. It is suggested that when the diameter of steel bar is 16mm in practicalengineering, the lapping length of high strength bars should not be less than 0. 80lab. The suggested lapping length can berefereed for high strength bars with other diameters, and be verified by the test before application.
Keywords:high strength steel bar; grouting-anchoring overlap-joint; spiral stirrup; lapping length; uniaxial tension
∗國家重點研發(fā)計劃項目(2022YFF0609200),上海市科學技術委員會項目(18DZ1205705).
第一作者:王卓琳,博士,教授級高級工程師,主要從事建筑檢測評估與加固改造領域的研究與實踐,Email: wzllzw@ 163. com.
[引用本文] 王卓琳,李向民,田坤,等. 螺旋箍筋約束高強鋼筋漿錨搭接單向拉伸試驗研究[J]. 建筑結構,2023,53(8):119-124. WANG Zhuolin,LI Xiangmin,TIAN Kun,et al. Uniaxial tension experimental study on the grouting-anchoringoverlap-joint of high strength steel bar restrained by spiral stirrups[J]. Building Structure,2023,53(8):119-124.
