The issue of building materials deterioration due to environmental actions, which are expected to worsen in the future according to climate change predictions, is recognized as high-priority by the scientific community. However, the impact of material deterioration on the structural and seismic performances of masonry and historical structures strengthened with composites has not been investigated in detail, even though potentially significant. This paper aims to evaluate the environmentally-induced loss of performance in fiber reinforced polymer (FRP) strengthening systems bonded to masonry structures. An efficient damaging block-based modelling strategy, recently developed by the authors, is used to model masonry. FRP strips are originally introduced in the model and bonded to masonry blocks through a contact-based formulation with cohesion. This novel numerical approach is validated through FRP-strengthened masonry wall benchmarks. Numerical analyses are performed on FRP-strengthened in- and out-of-plane loaded masonry full-scale walls and houses with non-degraded material properties to predict the structural response at design conditions. Then, degraded material properties are deduced from accelerated ageing laboratory tests which investigated environmental degradation in FRP-strengthened masonry and are adopted in the same numerical analysis framework to predict the structural response at degraded conditions. Therefore, the environmentally-induced loss of performance in FRP strengthening systems bonded to masonry structures is deduced by comparing the structural response at degraded conditions with the one at design conditions.

由于环境行动而导致的建筑材料劣化问题，根据气候变化的预测，这种情况预计将在未来加剧。科学界已将其列为高度优先事项。然而，尽管材料劣化对复合材料加固的砖石结构和历史结构的结构和抗震性能的影响，尽管可能具有重大意义，但尚未对其进行详细研究。本文旨在评估与砌体结构粘结的纤维增强聚合物（FRP）增强系统在环境中引起的性能损失。作者最近开发了一种有效的基于块的破坏性建模策略，用于对砌体进行建模。FRP条最初是引入模型中的，并通过具有粘性的基于接触的配方粘结到砖石砌块上。通过FRP加固的砌体墙基准测试验证了这种新颖的数值方法。在FRP加固的平面内和平面外砖砌全尺寸墙和具有未降解材料特性的房屋上进行了数值分析，以预测设计条件下的结构响应。然后，从加速老化的实验室测试推导出材料的性能下降，该实验室测试研究了FRP加固的砖石中的环境退化，并在相同的数值分析框架中采用了这种材料来预测退化条件下的结构响应。因此，通过将退化条件下的结构响应与设计条件下的结构响应进行比较，可以推断出与砌体结构粘合的FRP加固系统中环境引起的性能损失。