Development of FP Structural Members for Large-Scale Truss Structure

本文研究了一种适用于大型结构的FRP（纤维增强塑料）桁架构件。这种玻璃钢构件的金属部分在其末端用环氧胶粘剂粘合。大型桁架结构由这些构件在现场用螺栓连接而成。为提高结构材料的可靠性，构件安装了光纤传感器应变监测系统。首先，利用新开发的光纤传感器埋入玻璃钢模压成型的应变测量系统，对内部应变监测技术进行了研究。成型后，在应变监测实验中对传感器的损伤检测能力进行了测试。结果表明，光纤传感器在玻璃钢成型过程中具有应变测量能力，并能得到玻璃钢成型后的准确残余应变。传感器还可以测量FRP在循环加载条件下的应变，并通过应变监测检测FRP在循环加载条件下产生的损伤。最后，采用金属- frp粘接节点试件进行拉伸加载下的应变监测试验。实验结果表明，采用新开发的应变测量系统，通过应变监测可以检测到粘结区域的剥落，并获得其长度。在本研究中，可以研制出安装光纤传感器应变监测系统的FRP构件。该研究可为末端粘结金属连接件的玻璃钢构件拼装大型桁架结构的开发提供基本结果。

In the present study, an FRP(Fiber Reinforced Plastics) truss member for a large-scale structure was developed. This FRP member has metal parts bonded at its end with epoxy adhesives. The large-scale truss structure is assembled from these members bolted together in the field. The member was equipped with a strain monitoring system using optical fiber sensors for improving its structural material reliability. First, the internal strain monitoring technique was investigated by using the newly developed strain measurement system with the optical fiber sensors embedded in FRP during molding. After molding, an ability of the sensors for damage detection in the FRP was also examined in strain monitoring experiments. From the results, it was found that the optical fiber sensors have the strain measurement ability during molding of the FRP and their exactresidual strains after molding can be obtained. The sensors could also measure strains in the FRP under cyclic loading conditions and the damage generated in the FRP could be detected by their strain monitoring. Finally, metal-FRP adhesively bonded joint specimens were used for strain monitoring experiments under tensile loading. The experimental results showed that peeling of the bonded area can be detected and its length can be obtained with the strain monitoring by using newly developed strain measurement system.In this study, the FRP members could be developed which were equipped with the strain monitoring system with the optical fiber sensors. This study could yield the basic results of development for the large-scale truss structure assembled with the FRP members having metal jointing parts bonded at the end.