预应力碳纤维复材板加固桥梁短期预应力损失监测

SHORT-TERM PRESTRESS LOSS MONITORING FOR POST-TENSIONED CFRP LAMINATE STRENGTHENED BRIDGE

在介绍内嵌光纤光栅传感器(OFBG)的碳纤维复材板(CFRP)制作工艺和基本性能指标的基础上,结合大窑湾六号桥的病害检查评估工作,给出了相应的加固方案以及OFBG-CFRP智能板布设工艺,成功监测了后张预应力CFRP板加固施工阶段智能板的实时应力状态,并预测放张后锚具变形导致的短期预应力损失值。结果表明,埋入的光纤光栅(FBG)可以连续实时地监测CFRP板的应力状态,这种新型OFBG-CFRP智能板为桥梁结构加固施工阶段的健康诊断提供有效手段,同时,光纤光栅的稳定性与耐久性满足钢筋混凝土桥梁结构长期健康监测的要求。

The manufacture process and basic performance indicators of the novel carbon fiber reinforced polymer laminates embedded with optical fiber Bragg grating sensors(OFBG-CFRP laminate)were introduced.The reinforcement configuration and layout arrangement of the post-tensioned OFBG-CFRP laminate were given based on the disease evaluation of the Dayaowan No.6 Bridge,and then the real-time stress state of the posttensioned OFBGCFRP laminate during the prestressing construction stage was monitored successfully and the short-term prestress loss due to the anchorage deformation was further predicted accurately according to the formulation in the specification.The monitoring results showed that the embedded FBG sensors could monitor the real-time stress state of the CFRP laminate continuously and the novel OFBG-CFRP laminate could provide an effective measure for the bridge structure health diagnosis at the reinforcement construction stage.Besides,the long-term stability and durability of the FBG sensors could meet the requirements for the long-term health monitoring of reinforced-concrete bridge structure.