为探究CC(Concrete Canvas,混凝土帆布)+CFRP(Carbon Fiber Reinforced Plastic,碳纤维增强复合材料)约束对钢筋混凝土方柱力学性能的影响,设计了8组16个CC+CFRP联合加固的钢筋混凝土方柱轴心受压试验。分析了CFRP条带约束、全包约束和CFRP包裹层数对CC+CFRP联合加固柱破坏形态、承载力和延性的影响。研究结果表明:联合加固下CFRP的约束方式和包裹层数对钢筋混凝土方柱的力学性能有显著影响;在承载力提升方面,CFRP条带包裹要优于整体包裹,且CFRP包裹层数为2时的承载力提高幅度最大;在变形方面,CC的存在能够改善柱的破坏形态,提高试件的延性和变形能力。研究成果对于减轻内部钢筋腐蚀及提高混凝土结构的耐久性有一定参考价值。
Abstract
In order to investigate the joint strengthening effect of Concrete Canvas (CC) and Carbon Fiber Reinforced Plastic (CFRP) on the mechanical properties of reinforced concrete square column, we designed axial compression tests on eight groups of sixteen CC+CFRP reinforced columns, and examined the influences of CFRP band constraint, full constraints and the number of CFRP layers on the failure mode, bearing capacity and ductility of CC+CFRP reinforced columns. Results reveal that the mechanical properties of reinforced concrete square columns are remarkably affected by the restraint mode and quantity of CFRP layers under joint strengthening. CFRP band wrapping is superior to full wrapping in terms of improving bearing capacity, and the bearing capacity of column strengthened by two layers of CFRP improves the most. In terms of deformation, CC ameliorates the failure form of the column, and enhances the ductility and deformation capacity of the column. The research results are of referential value to reducing the corrosion of reinforced steel and upgrading the durability of concrete structures.
关键词
钢筋混凝土方柱 /
混凝土帆布 /
CC+CFRP联合加固 /
轴心受压 /
力学性能
Key words
reinforced concrete square column /
concrete canvas /
CC+CFRP joint reinforcement /
axial compression /
mechanical properties
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参考文献
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基金
国家自然科学基金项目(51968058);内蒙古自治区青年科技英才支持计划项目(NJYT-18-A06);内蒙古自治区人才开发基金项目