- 摘 要
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（1 中設(shè)設(shè)計集團股份有限公司， 南京 210000；2東南大學(xué)土木工程學(xué)院， 南京 210096；3 湘潭大學(xué)土木工程與力學(xué)學(xué)院， 湘潭 411100; 4 江蘇東部高速公路管理有限公司， 鹽城 224002）
［摘要］通過對1根未加固對比梁和3根加固梁進(jìn)行正截面四點彎試驗研究，探討了二次受力對聚乙烯醇纖維增強鋼絲網(wǎng)水泥基復(fù)合材料（PVA-RFCC）加固RC梁彎曲性能的影響。結(jié)果表明：PVA-RFCC是一種有效的加固材料，與加固對比梁相比，二次受力對PVA-RFCC加固RC梁的極限承載力和剛度系數(shù)（屈服階段）影響比較小，但開裂荷載和剛度系數(shù)（彈性階段）均降低約30%。二次受力對試驗梁的抗彎性能影響與試驗梁在加固之前的損傷程度有關(guān)；當(dāng)損傷程度分別為加固對比梁的27.6%，82.8%時，位移延性系數(shù)分別增加54.1%和降低26.6%。因此，當(dāng)梁處于初始損傷狀態(tài)時對其進(jìn)行加固，可以提高梁的綜合力學(xué)性能。
［關(guān)鍵詞］二次受力； PVA-RFCC； 抗彎性能； 剛度系數(shù)； 位移延性系數(shù)； 損傷程度
中圖分類號：TU375文獻(xiàn)標(biāo)識碼：A文章編號：1002-848X(2020)15-0015-05
Experimental study on flexural behavior of RC beams strengthened with PVA-RFCC under secondary load
YUAN Weiwei1, DU Wenping2, YANG Caiqian2,3, WANG Chong2, ZHU Fawang2, PAN Yong4, MENG Chunlin4
(1 China Design Group Co., Ltd., Nanjing 210000, China; 2 School of Civil Engineering, Southeast University, Nanjing 210096, China; 3 College of Civil Engineering and Mechanics, Xiangtan University, Xiangtan 411100, China; 4 Jiangsu Eastern Expressway Management Co., Ltd.， Yancheng 224002, China)
Abstract:A four-point bending experimental of one unstrengthened control beam for comparison and three strengthened beams were investigated. The influence of secondary load on the flexural behavior of RC beams strengthened with polyvinyl alcohol fiber reinforced ferrocement cementitious composite (PVA-RFCC) was discussed. The results shows that PVA-RFCC is the most excellent strengthening materials. Compared with strengthened control beam, the secondary load of RC beams strengthed with PVA-RFCC has little influence on load carrying capacity and stiffness coefficient in the yielding stage. But the cracking load and stiffness coefficient in the elastic stage of strengthened beams all decreased about 30% under secondary load. The influence of secondary load on the flexural behavior is related to the damage degree of beams before reinforcement. When the damage degrees of the strengthened beam are 27.6% and 82.8%, the displacement ductility coefficient increased by 54.1% and decreased by 26.6% respectively. Therefore, the beams should be strengthened when they are in initial damage state, which can improve the comprehensive mechanical properties.
Keywords:secondary load; PVA-RFCC; flexural behavior; stiffness coefficient; displacement ductility coefficient; damage degree
*湖南省重點研發(fā)計劃（2018WK2111），湖南省創(chuàng)投項目（2018GK5028）。
作者簡介：袁微微，碩士，高級工程師，Email:38836669@qq.com；通訊作者：楊才千，博士，教授，Email:ycqjxx@seu.edu.cn。
