聚乙烯醇纖維水泥砂漿鋼筋網(wǎng)加固RC柱偏壓性能試驗研究*
卜良桃,袁超,魯晨,陶劍劍
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卜良桃,袁超,魯晨,陶劍劍(湖南大學(xué)土木工程學(xué)院, 長沙 410082)[摘要]針對采用聚乙烯醇纖維水泥砂漿(PVAECC)鋼筋網(wǎng)加固的RC柱的一次受力偏壓性能進行了研究。通過對8根大、小偏心受壓柱在單調(diào)荷載作用下的對比試驗,研究分析了這種加固方法對偏壓柱的極限承載力、破壞形態(tài)、荷載撓度曲線及裂縫分布等的影響機理和規(guī)律。試驗結(jié)果表明,PVA-ECC鋼筋網(wǎng)薄層加固是一種有效的加固方法,能夠較顯著地提高偏壓RC柱的承載力、峰值應(yīng)變、延性、剛度及抗裂性能。最后,在考慮截面有效約束區(qū)和非有效約束區(qū)及界面?zhèn)鬟f剪力的基礎(chǔ)上,建立了PVA-ECC加固鋼筋混凝土偏壓柱的承載力計算公式。[關(guān)鍵詞]聚乙烯醇纖維水泥砂漿;鋼筋網(wǎng);偏壓柱;一次受力;承載力中圖分類號:TU375.3 文獻標(biāo)識碼:A 文章編號:1002-848X(2013)08-0082-07Study on bearing capacity of PVA-ECC steel mesh reinforced concrete column subjected to eccentric loadBu Liangtao, Yuan Chao, Lu Chen, Tao Jianjian(Civil Engineering College, Hunan University, Changsha 410082, China)Abstract: Bearing capacity of polyvinyl alcohol-engineered cementitious composites(PVAECC)steel mesh reinforced concrete column subjected to one-off eccentric load was studied. Comparison experiments of 8 specimens including large eccentric columns and small eccentric columns under monotonic loadings were conducted, in which the influence of this kind of strengthening method on ultimate bearing capacity, failure mode, load-deflection curve and the cracking behavior of the columns were analyzed. Results show that PVA-ECC steel mesh technology greatly increases the bearing capacity, peak strain, ductility, stiffness and crack resistance properties of strengthened columns. The formula of bearing capacity of strengthened columns is set up, considering the effectively confined area and the ineffectively confined area in the column section and the transfer of shear force.Keywords: polyvinyl alcohol-engineered cementitious composite; steel mesh; eccentrically loaded column; one-off load; bearing capacity*長沙市科技重點項目(K110911511)。作者簡介:卜良桃,教授,Email:plt63@126.com。參考文獻[1]尚守平,蔣隆敏,張毛心.鋼筋網(wǎng)水泥復(fù)合砂漿加固RC偏心受壓柱的試驗研究[J].建筑結(jié)構(gòu)學(xué)報,2005,26(2):18-25.[2]龍凌霄,尚守平,劉方成.復(fù)合砂漿鋼筋網(wǎng)加固混凝土構(gòu)件粘結(jié)機理探討[J].山西建筑,2005,31(7):94-95.[3]卜良桃,萬長勝,尹鵬.PVA-ECC加固RC足尺梁受彎性能試驗研究[J].湖南大學(xué)學(xué)報:自然科學(xué)版,2010,37(1):5-10.[4]卜良桃,陳軍,魯辰.PVA-ECC加固RC足尺梁二次受力試驗研究[J].湖南大學(xué)學(xué)報:自然科學(xué)版,2011,38(1):1-7.[5]卜良桃,曾堅,李為.鋼纖維水泥砂漿鋼筋網(wǎng)加固RC梁抗剪試驗研究[J].湖南大學(xué)學(xué)報:自然科學(xué)版,2012,39(2):7-11.[6]歐陽煌,黃奕輝,錢在茲,等. 玻璃纖維(GFRP) 片材約束混凝土的受力性能分析[J].土木工程學(xué)報,2004,37(3):26-34.[7]卜良桃,李易越,袁超,等. PVA-ECC加固RC方柱軸壓性能試驗研究[J]. 建筑結(jié)構(gòu),2012,42(7):97-102.[8]MANDER J B, PRIESTLEY M J N, PARK R. Observed stress-strain behavior of confined concrete[J]. Journal of Structural Engineering, 1988,114(8):1827-1849.[9]毛海斌.鋼纖維水泥砂漿鋼筋網(wǎng)加固RC方柱試驗研究[D].長沙:湖南大學(xué),2011.