Reinforced Concrete Pipes (RCP) has been widely used for long-distance sewerage pipeline globally. However, concrete pipes are susceptible to microbially-induced acid corrosion (MIC) which leads to premature failure far before reaching their asset life. The aim of this study is to investigate the effectiveness and efficiency of using CAC (Calcium Aluminate Cement) – GGBFS (Ground Granulated Blast Furnace Slag) blended SHCC (Strain hardening cementitious composite) to retrofit damaged RCP. Prior to the retrofit, RCP was pre-loaded to 70%, 80%, 90% of its ultimate strength to create cracks. Retrofitted pipes were tested under three-edge bearing (TEB) load for assessment. Load–deflection relationship, load–strain behaviour along with pipe ductility and stiffness were analysed and discussed. Experimental results show that the ultimate load-carrying capacity of the retrofitted RCP increased up to 50.6% compared to original RCP. The retrofitted pipe acted monolithically with the lining material without debonding observed before failure. Moreover, a prediction formula was proposed to calculate the load-bearing capacity of retrofitted RCP in addition to experimental work. The theoretical model considers the impact of the pre-loading level on the original RCP and was verified with the experimental results. CAC-GGBFS blended SHCC is proven to be an effective repair solution to damaged concrete sewerage pipelines.

钢筋混凝土管（RCP）已在全球范围内广泛用于长距离污水管道。然而，混凝土管道容易受到微生物引起的酸腐蚀 (MIC) 的影响，这会导致在达到其资产寿命之前过早失效。本研究的目的是研究使用 CAC（铝酸钙水泥）-GGBFS（磨碎高炉渣）混合 SHCC（应变硬化水泥复合材料）来改造损坏的 RCP 的有效性和效率。在改造之前，RCP 被预加载到其极限强度的 70%、80%、90% 以产生裂缝。改造后的管道在三边轴承 (TEB) 载荷下进行了测试以进行评估。分析和讨论了载荷-挠度关系、载荷-应变行为以及管道延性和刚度。实验结果表明，改造后的RCP的极限承载能力比原来的RCP提高了50.6%。改造后的管道与衬里材料一起作用，在失效前没有观察到脱粘。此外，除了实验工作之外，还提出了一个预测公式来计算改造后的RCP的承载能力。理论模型考虑了预载水平对原RCP的影响，并与实验结果进行了验证。CAC-GGBFS 混合 SHCC 被证明是修复受损混凝土污水管道的有效解决方案。除了实验工作外，还提出了计算加装RCP承载能力的预测公式。理论模型考虑了预载水平对原RCP的影响，并与实验结果进行了验证。CAC-GGBFS 混合 SHCC 被证明是修复受损混凝土污水管道的有效解决方案。除了实验工作外，还提出了计算加装RCP承载能力的预测公式。理论模型考虑了预载水平对原RCP的影响，并与实验结果进行了验证。CAC-GGBFS 混合 SHCC 被证明是修复受损混凝土污水管道的有效解决方案。