- 摘 要
-
(1 西南交通大學(xué)土木學(xué)院,成都 610031;2 西南科技大學(xué)土木工程與建筑學(xué)院,綿陽 621010)
［摘要］對采用反向起拱粘貼碳纖維布加固混凝土梁構(gòu)件的基本原理和設(shè)計方法進(jìn)行了初步研究，提出了基于預(yù)應(yīng)力原理的反拱法碳纖維布材加固梁構(gòu)件的施工工藝。在此基礎(chǔ)上，進(jìn)行了3根試件的試驗。通過試驗結(jié)果對比了不同加固工藝的受彎構(gòu)件的開裂荷載、極限荷載、抗彎剛度等工作性能，分析了反拱加固的預(yù)應(yīng)力效應(yīng)。試驗發(fā)現(xiàn)，反拱加固試件的開裂荷載較普通粘貼加固試件的開裂荷載提高了36.2%，屈服條件下的變形減小了24.2%。試驗結(jié)果表明，采用反拱加固可方便有效地卸除加固構(gòu)件的殘余應(yīng)力，并產(chǎn)生預(yù)應(yīng)力效應(yīng)，可充分發(fā)揮碳纖維布材料高強(qiáng)度的特性，提高構(gòu)件剛度和承載能力。
［關(guān)鍵詞］反拱；預(yù)應(yīng)力；碳纖維布；加固；梁構(gòu)件
中圖分類號：TU375-05文獻(xiàn)標(biāo)識碼：A文章編號：1002-848X(2012)03-0104-03
Study of strengthened reinforced concrete beams with additional reversed deflection
Gu Song1, 2, Yao Yong2, Zhao Lei1, Chen Daiguo2（1 School of Civil Engineering, Southwest Jiaotong University, Chengdu 610031, China; 2 School of Civil Engineering and Architecture, Southwest University of Science and Technology, Mianyang 621010, China)
Abstract:The mechanism of using carbon fiber reinforced plastics (CFRP) sheet to strengthen reinforced concrete beams with additional reversed deflection operation was proposed. Three specimens were tested to investigate the working performance of these beams. The strengthening effects, such as cracking load, ultimate load and flexural stiffness between non-strengthened beams and strengthened beams with either reversed deflection method or traditional method were compared. The effect of pre-stressing caused by reversed deflection was verified through theoretical derivation and experimental results. Compared with the beam strengthened with traditional method, strengthened beam with reversed deflection can enhance the crack load by 36.2%, and the deformation of the beam under yield load can decrease by 24.2%, which means strengthened beam with reversed deflection can unload the residual stress of the beam effectively and cause pre-stress effects, which will utilize more tensile strength of the CFRP and largely improve the performance of the beams.
Keywords:additional reversed deflection; pre-stress; CFRP; strengthened; beam member
*國家863計劃資助（2009AA032304）。
作者簡介：古松，副教授，Email：gusong@swust.edu.cn。
參考文獻(xiàn)
［1］李貴炳,張愛暉,金偉良.鋼筋混凝土梁加固時的既有荷載對其抗彎性能的影響［J］.土木工程學(xué)報，2006，39(1)：13-20.
［2］王榮國,代成琴,劉文博,等.CFRP加固混凝土梁抗彎極限承載力的計算分析［J］.哈爾濱工業(yè)大學(xué)學(xué)報,2002,34(3):312-319.
［3］王苗春,馮振宇.不同卸載時外貼CFRP加固RC梁正截面承載力計算［J］.石家莊鐵道學(xué)院學(xué)報,2004,17(1):72-75.
［4］王滋軍,劉偉慶,姚秋來,等.考慮二次受力的碳纖維加固鋼筋混凝土梁抗彎性能的試驗研究［J］.工業(yè)建筑，2004,34(7):85-87.
［5］尚守平,彭暉,童樺,等.預(yù)應(yīng)力碳纖維布材加固混凝土受彎構(gòu)件的抗彎性能研究［J］.建筑結(jié)構(gòu)學(xué)報,2003,24(5):24-30.
［6］張軻,葉列平,岳清瑞.預(yù)應(yīng)力碳纖維布加固鋼筋混凝土T形梁試驗研究［J］.工業(yè)建筑,2006,36(12):86-95.
［7］趙軍讓.采用體外預(yù)應(yīng)力技術(shù)對鋼筋混凝土梁的加固［J］.科技情報開發(fā)與經(jīng)濟(jì),2007,17(14):187-188.
［8］劉國義,王守國,陳艷和,等.外部預(yù)應(yīng)力碳化纖維復(fù)合纜繩在混凝土梁加固中的應(yīng)用［J］.國外油田工程,2005,21(11):39-43.
［9］陸春陽.混凝土受彎構(gòu)件正截面抗裂彎矩計算［J］.廣西大學(xué)學(xué)報:自然科學(xué)版,2005，30（3）:181-183
