In this study, the well-established service life design code defined in fib Bulletin 34 is adapted to predict the time to initiation of reinforcement corrosion in alkali-activated concretes submerged in marine conditions. The model approach is based on the probabilistic calculation of the time needed for a critical concentration of chloride ions, migrating from the external environment towards the rebar, to accumulate at the surface of the steel reinforcement and initiate the corrosion reaction. The information required to define the parameters of the model is derived from literature data, relating the concrete mix designs with accelerated laboratory test results. The findings indicate that alkali-activated concretes with high calcium content can exhibit promising characteristics as a construction material applied for structural application in chloride-rich corrosive environments. The probabilistic approach adopted in this model provides the opportunity to assess the influence of variability in mineralogical composition and reactivity of the precursors with the alkaline activating solution, that influence the chemical evolution and microstructure of the binder matrix. The predicted service life is quite sensitive to these factors, with very high service lives predicted for some alkali-activated concretes but rather short service lives predicted for others, and this must be incorporated into any engineering assessment of future material performance.

在这项研究中，采用fib公告 34中定义的完善的使用寿命设计规范来预测浸没在海洋条件下的碱激活混凝土中钢筋开始腐蚀的时间。该模型方法基于对氯离子临界浓度从外部环境迁移到钢筋、在钢筋表面积聚并引发腐蚀反应所需时间的概率计算。定义模型参数所需的信息来自文献数据，将混凝土配合比设计与加速实验室测试结果相关联。研究结果表明，高钙含量的碱激活混凝土作为一种在富含氯化物的腐蚀环境中用于结构应用的建筑材料可以表现出有前景的特性。该模型中采用的概率方法提供了评估矿物成分变化以及前体与碱性活化溶液的反应性的影响的机会，这些变化影响粘合剂基质的化学演化和微观结构。预测的使用寿命对这些因素非常敏感，一些碱激活混凝土的预计使用寿命非常高，而其他混凝土的预计使用寿命则相当短，这必须纳入对未来材料性能的任何工程评估中。