- 摘 要
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（大連理工大學海岸和近海工程國家重點實驗室， 大連 116024）
［摘要］通過四點彎曲試驗，研究并分析了在干濕循環(huán)和持續(xù)荷載共同作用下CFRP加固高強混凝土梁的耐久性。干濕循環(huán)介質(zhì)采用3-5%的NaCl溶液，循環(huán)次數(shù)設(shè)置0次、40次、80次和120次，持載等級為未加固鋼筋混凝土梁極限荷載的0%，30%和60%。試驗結(jié)果表明：干濕循環(huán)和持載作用后，加固梁的性能發(fā)生劣化，破壞方式逐漸由混凝土表層破壞向膠層與混凝土之間的粘結(jié)破壞發(fā)展；加固梁的極限荷載、跨中極限撓度、CFRP極限應(yīng)變整體呈下降趨勢，后期剛度顯著降低，且隨著持載等級提高，退化程度進一步加劇。
［關(guān)鍵詞］高強混凝土； CFRP； 干濕循環(huán)； 持續(xù)荷載
中圖分類號：TU375文獻標識碼：A文章編號：1002-848X(2017)21-0078-06
Durability study of high strength concrete beams strengthened with CFRP under sustained load and dry-wet cycle conditions
Wang Suyan, Ding Li, Hong Lei, Song Zelin
(State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China)
Abstract:Through the four-point bending test, the durability of CFRP reinforced concrete beams under the combined conditions of dry-wet cycles and sustained load was studied and analyzed. The dry-wet cycle medium adopted 3-5% NaCl solution, and the cycle times were set as 0, 40, 80 and 120 times, and the sustained loading grades were 0%, 30% and 60% of the ultimate load of the unreinforced concrete beam. Experimental results show that the performances of the strengthened beams are deteriorated after dry-wet cycles and sustained load, and the failure mode gradually develops from the damage of concrete surface to the bonding between adhesive layer and concrete; ultimate load, ultimate deflection at mid-span and ultimate strain of CFRP overall show a downward trend, and the rigidity in later stage decreases significantly, and the degradation degree further aggravates with the increase of sustained load level.
Keywords:high strength concrete; Carbon Fiber Reinforced Polymer(CFRP); dry-wet cycle; sustained load
*國家自然科學基金項目（51378089）。
作者簡介：王蘇巖，本科，教授，碩士生導師， Email: suyanw@dlut.edu.cn。
