| 摘要: |
| 玄武岩纤维增强复合材料(Basalt Fiber Reinforced Polymer,BFRP)具有轻质、高强、耐腐蚀、耐疲劳等优点,特别适用于受腐蚀环境因素影响较大的结构工程。预应力钢筒混凝土管(Prestressed Concrete Cylinder Pipe,PCCP)是一种优秀的引调水工程管材,为解决因钢丝腐蚀和氢脆导致的断丝风险,从根本上提升PCCP安全性和耐久性,本文提出采用BFRP筋代替高强钢丝制作新型PCCP并开展研究。通过开展BFRP筋不同弯曲直径下的抗拉强度试验,分析得到BFRP筋抗拉强度退化规律,获取弯曲状态下BFRP筋抗拉强度折减系数,并基于数理统计提出该系数的经验公式。结果表明：BFRP筋弯曲状态下应力-应变关系仍保持线性关系,极限拉伸断裂属于脆性破坏；极限强度较直线状态折减明显,提出的抗拉强度折减系数公式可以较为准确的预测弯曲状态下BFRP筋极限抗拉强度,当弯曲直径为2.8 m时,BFRP筋弯曲抗拉强度较直线状态下降了22.3％,弯曲直径越大,BFRP筋强度越能得到更充分的利用。 |
| 关键词: BFRP筋 PCCP 弯曲状态 抗拉性能 折减系数 |
| DOI： |
| 分类号:TB332 |
| 基金项目:中央级公益性科研院所基本科研业务费专项资金(Y424014,Yy424009)；环北部湾广东水资源配置工程课题研究(XJLY-2022HT-62) 通信作者：李军(1974-),男,安徽东至人,正高级工程师,研究方向为水工结构健康诊断与安全评价等方面。E-mail: junli@nhri.cn ,2,3,翟俊杰1,石中文1,潘文明1,王旭东2 |
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| Tensile performance with bending of BFRP tendons used for PCCP |
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LI Jun1,2,3,2,4,2, ZHAI Junjie1, SHI Zhongwen1, PAN Wenming1, WANG Xudong3
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1.Materials and Structure Research Institute,Nanjing Hydraulic Research Institute;2.China;3.College of Water Conservancy and Hydropower Engineering,Hohai University;4.The National Key Laboratory of Disaster Prevention
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| Abstract: |
| Basalt Fiber Reinforced Polymer (BFRP) composite materials possess advantages such as lightweight, high strength, corrosion resistance, and fatigue resistance, making them particularly suitable for structural engineering affected by corrosive environmental factors. Prestressed Concrete Cylinder Pipe (PCCP) is an excellent material for water diversion projects. To fundamentally enhance the safety and durability of PCCP by addressing the risk of wire breakage due to steel wire corrosion and hydrogen embrittlement, this paper proposes the use of BFRP tendons to replace high-strength steel wire in the production of a new type of PCCP and conducts research. By performing tensile strength tests on BFRP tendons with different bending diameters, the degradation pattern of the tensile strength of BFRP tendons is analyzed, and a reduction coefficient for the tensile strength of BFRP tendons in a bent state is obtained. An empirical formula for this coefficient is proposed based on statistical analysis. The results indicate that the stress-strain relationship of BFRP tendons in a bent state remains linear, and the ultimate tensile fracture is characterized as brittle failure; the ultimate strength significantly decreases compared to the linear state. The proposed tensile strength reduction coefficient formula can accurately predict the ultimate tensile strength of BFRP tendons in a bent state. When the bending diameter is 2.8m, the bending tensile strength of BFRP tendons decreases by 22.3% compared to the linear state, and the greater the bending diameter, the more effectively the strength of BFRP tendons can be utilized. |
| Key words: BFRP tendons PCCP Bending Tensile strength Reduction factor |
