自然暴露环境下预应力CFRP加固RC梁长期性能演化测试及表征

The long-term behavior of reinforce concrete (RC) members strengthened with prestressed carbon fiber reinforced polymer (CFRP) is discussed considering the real service status (natural exposure and loads coupling action). Based on the RC beams strengthened with prestressed CFRP, the measurement and characterization method of long-term behavior of members under the natural exposure and loads coupling action are discovered in this research. On the one hand, an experimental program is conducted to investigate the combined effects of sustained loads and natural exposure on the RC beams strengthened with prestressed CFRP during long term. During the program, the parameters of specimens, temperature, and humidity of environment are measured by systems designed in this research. From the test results, the regular and influencing factors of prestress losses of RC beams strengthened with prestressed CFRP under the natural exposure and loads coupling action are discussed.On the other hand, the constitutive relations of concrete, the performance of interface of CFRP-concrete, and the long-term performance of RC beams strengthened with prestressed CFRP after different natural exposure time are discussed with the experimental studies and theoretical analyses. And then, the influence factors and characterization method to describe the evolution law of mechanical performance of RC beams strengthened with prestressed CFRP under natural exposure and loads are proposed, which provide a scientific basis for prestressed CFRP technique to design, maintenance and management of the servicing bridges.

针对预应力碳纤维增强复合材料（CFRP）加固钢筋混凝土（RC）桥梁结构在实际服役状态下的长期力学行为，以预应力CFRP加固RC梁为研究对象，探讨自然暴露环境与载荷耦合作用下加固梁长期力学性能演化的测试和表征方法。一方面，探讨预应力CFRP加固RC梁在持载下的长期自然暴露实验和测试方法及技术，研发实验装置，再现预应力CFRP加固RC梁的服役状态，并对其力学和环境参数进行实时测量，探明自然暴露环境与载荷耦合作用下加固梁的预应力损失规律及影响因素；另一方面，通过不同暴露周期下混凝土的本构关系、CFRP-混凝土界面性能演化、加固梁长期力学性能的实验研究和理论分析，揭示自然暴露环境对预应力CFRP加固RC梁力学性能演化规律的影响机制，提出自然暴露环境与载荷耦合作用下预应力CFRP加固RC梁长期力学性能演化的表征方法，为预应力CFRP技术在运营及新建桥梁中的设计、养护和管理提供科学依据。

针对预应力碳纤维增强复合材料（CFRP）加固钢筋混凝土（RC）桥梁结构在实际服役状态下的长期力学行为，以预应力CFRP加固RC梁为研究对象，探讨自然暴露环境与载荷耦合作用下加固梁长期力学性能演化的测试和表征方法。一方面，探讨预应力CFRP加固RC梁在持载下的长期自然暴露实验和测试方法及技术，研发实验装置，再现预应力CFRP加固RC梁的服役状态，并对其力学和环境参数进行实时测量，探明自然暴露环境与载荷耦合作用下加固梁的预应力损失规律及影响因素；另一方面，通过不同暴露周期下混凝土的本构关系、CFRP-混凝土界面性能演化、加固梁长期力学性能的实验研究和理论分析，揭示自然暴露环境对预应力CFRP加固RC梁力学性能演化规律的影响机制，提出自然暴露环境与载荷耦合作用下预应力CFRP加固RC梁长期力学性能演化的表征方法，为预应力CFRP技术在运营及新建桥梁中的设计、养护和管理提供科学依据。