The hygrothermal aging of fiber reinforced polymer (FRP) composite rod served as bridge cables played a key role on the long-term service performances. In the present paper, two types of pultruded carbon/glass fiber reinforced epoxy hybrid composite rods, one with uniformly dispersed carbon and glass fibers, and the other with glass fiber shell and carbon fiber core, were investigated on the water uptake and interface shear strength. The aging condition was immersion in deionized water at 40 °C, 60 °C and 80 °C. Interface shear strength degradation mechanism was revealed by thermal analysis and microstructure analysis. It was found that the water absorption of two types of hybrid rods represented the two-stage behavior. For the rod of uniform fiber dispersion, more water uptake in the second stage occurred compared to that of the shell/core rod, which was attributed to the resin rich area and interface debonding of fiber/resin. Long-term hygrothermal exposure led to a remarkable degradation in the interfacial shear strength of the rods, up to 17.5% ∼ 42.1%. The resin plasticization and interface debonding were the main factors contributed to the strength degradation. Based on the Arrhenius equation, the long-term life prediction of the interfacial shear strength under two typical bridge service environments was conducted to the design guideline of hybrid rods in the bridge engineering.

用作桥梁缆索的纤维增强聚合物（FRP）复合杆的湿热老化对长期使用性能起着关键作用。在本文中，研究了两种拉挤碳/玻璃纤维增​​强环氧树脂混合复合材料棒的吸水率和界面剪切强度，一种具有均匀分散的碳和玻璃纤维，另一种具有玻璃纤维壳和碳纤维芯。 . 老化条件为浸入40℃、60℃和80℃的去离子水中。通过热分析和微观结构分析揭示了界面剪切强度退化机制。发现两种混合棒的吸水率代表了两阶段行为。对于纤维分散均匀的棒，与壳/芯棒相比，第二阶段发生了更多的吸水，这归因于富含树脂的区域和纤维/树脂的界面脱粘。长期湿热暴露导致棒的界面剪切强度显着下降，下降幅度高达 17.5% ~ 42.1%。树脂塑化和界面脱粘是导致强度下降的主要因素。基于Arrhenius方程，对两种典型桥梁使用环境下的界面抗剪强度长期寿命预测作为桥梁工程中混合杆的设计指南。树脂塑化和界面脱粘是导致强度下降的主要因素。基于Arrhenius方程，对两种典型桥梁使用环境下的界面抗剪强度长期寿命预测作为桥梁工程中混合杆的设计指南。树脂塑化和界面脱粘是导致强度下降的主要因素。基于Arrhenius方程，对两种典型桥梁使用环境下的界面抗剪强度长期寿命预测作为桥梁工程中混合杆的设计指南。