PRESTRESSED CARBON FIBER REINFORCED POLYMER SHEETS FOR STRENGTHENING CONCRETE BEAMS AT ROOM AND LOW TEMPERATURES
PRESTRESSED CARBON FIBER REINFORCED POLYMER SHEETS FOR STRENGTHENING CONCRETE BEAMS AT ROOM AND LOW TEMPERATURES
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DOI：
10.1061/(asce)1090-0268(2004)8:1(3
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发表时间：
2004-02
影响因子：
4.6
通讯作者：
R. El-Hacha;R. Wight;M. Green
中科院分区：
文献类型：
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作者：
R. El-Hacha;R. Wight;M. Green
女王大学和加拿大皇家军事学院开发了一种使用预应力碳纤维增强聚合物（CFRP）板加固受损混凝土梁的技术。作为本研究的一部分，开发了一种锚固系统，通过顶升和对加固混凝土梁本身的反作用力，直接对 CFRP 板施加预应力。已经通过实验研究了在室温（+22°C，+72°F）和低温（-28°C，-20°F）下使用粘合预应力 CFRP 板加固预裂混凝土梁的可行性和有效性。研究了温度变化引起的材料和预应力变化，这些变化会影响并导致弯曲行为的变化。与控制未强化梁相比，强化梁的弯曲刚度和极限承载力显着增加。短期暴露于低温（-28°C，-20°F）不会对加固梁的弯曲性能产生不利影响。除了实验研究之外，还开发了分析模型来预测加固梁在 CFRP 板预应力期间以及在室温和低温下的外部载荷下的整体弯曲行为。该模型准确地预测了弯曲梁的行为。预计使用粘合预应力 CFRP 片材加固的梁可改善使用性能并提高强度。
A technique for strengthening damaged concrete beams using prestressed carbon fiber reinforced polymer (CFRP) sheets was developed at Queen’s University and the Royal Military College of Canada. As part of this study, an anchorage system was developed to directly prestress the CFRP sheets by jacking and reacting against the strengthened concrete beam itself. The feasibility and effectiveness of using bonded prestressed CFRP sheets to strengthen precracked concrete beams at both room (+22°C,+72°F) and low (-28°C,-20°F) temperatures have been investigated experimentally. Materials and prestress changes due to temperature variations that would affect and cause changes in flexural behavior were studied. The strengthened beams showed significant increases in flexural stiffness and ultimate capacity as compared to the control-unstrengthened beams. The flexural behavior of the strengthened beams was not adversely affected by short-term exposure to reduced temperature (-28°C,-20°F). In addition to the experimental investigation, analytical models were developed to predict the overall flexural behavior of the strengthened beams during prestressing of the CFRP sheets and under external loading at both room and low temperatures. The model accurately predicted the flexural beam behavior. Improved serviceability behavior and higher strength were predicted for beams strengthened with the bonded prestressed CFRP sheets.