In this paper, the bond durability of glass fiber-reinforced polymer (GFRP) bars in seawater sea-sand concrete (SWSSC) under the coupling effect of seawater immersion and sustained load was experimentally investigated. The test parameters included bar diameter (12 and 16 mm), immersion time (90, 180, and 270 days), and sustained load condition (loaded and unloaded). Test results showed that for the specimens with a small bar diameter, the bond strength had a slight growth at the initial stage of exposure mainly due to the water swelling of the bar, and then decreased due to the bond degradation. For the specimens with a large bar diameter, the bond strength increased with the increase of immersion time, which was determined by the increasing compressive strength of SWSSC. The sustained load reduced the bond strength of the specimens with a small bar diameter due to its acceleration of bond degradation, but had little effect on the bond strength of the specimens with a large bar diameter. The degradation mechanism was the rib deterioration of the bars caused by seawater immersion. Moreover, the sustained load could accelerate the degradation. The predicted bond strength retention of the specimen with a bar diameter of 12 mm under the coupling effect of the marine environment (moisture saturated and the mean annual temperature of 25–35 °C) and sustained load is 52% after 50 years of service.

本文对海水浸泡和持续荷载耦合作用下玻璃纤维增​​强聚合物(GFRP)钢筋在海水海砂混凝土(SWSSC)中的粘结耐久性进行了实验研究。测试参数包括钢筋直径（12 和 16 毫米）、浸泡时间（90、180 和 270 天）和持续负载条件（加载和卸载）。试验结果表明，对于细棒直径的试件，在暴露初期粘结强度略有增长，主要是由于棒的水溶胀，然后由于粘结退化而下降。对于钢筋直径较大的试件，其结合强度随着浸泡时间的增加而增加，这是由 SWSSC 的抗压强度增加决定的。持续载荷会加速小棒直径试样的粘结退化，降低其粘结强度，但对大棒直径试样的粘结强度影响不大。退化机制是海水浸泡引起的钢筋肋条退化。此外，持续的负载可能会加速退化。在海洋环境（水分饱和和年平均温度为 25-35 °C）和持续载荷的耦合作用下，钢筋直径为 12 mm 的试件在使用 50 年后的预测粘结强度保持率为 52%。退化机制是海水浸泡引起的钢筋肋条退化。此外，持续的负载可能会加速退化。在海洋环境（水分饱和和年平均温度为 25-35 °C）和持续载荷的耦合作用下，钢筋直径为 12 mm 的试件在使用 50 年后的预测粘结强度保持率为 52%。退化机制是海水浸泡引起的钢筋肋条退化。此外，持续的负载可能会加速退化。在海洋环境（水分饱和和年平均温度为 25-35 °C）和持续载荷的耦合作用下，钢筋直径为 12 mm 的试件在使用 50 年后的预测粘结强度保持率为 52%。