This paper presents theoretical and experimental investigations to analyze the flexural behavior of reinforced concrete beams strengthened with a cementitious mortar based on the dune sand varying the cover thickness and the reinforcement ratio. After a suitable cure of beam specimens in the laboratory, they submitted to progressive loadings until the failure. The results obtained show that the flexural capacity of the strengthened beam is about 134.44 KN, which is 96% of that of the reference beam for a reinforcement ratio of 1.2% environ (over-reinforcement section). However, for ratios of 0.5% and 0.8% environ (under-reinforcement section), the flexural peak load and the failure load of the strengthened beam and those of the reference beam are similar. Deflections of strengthened beams are in general reduced compared to those of reference beams. The repair dune sand mortar could be used to enhance the flexural capacity and the ductility of damaged reinforced concrete beams strengthened with dune sand mortars. Theoretical results compared to those obtained from experimental tests, in terms of deflections and ductility, are generally in good agreement.

中文翻译：

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沙丘砂水泥砂浆加固钢筋混凝土梁的理论与试验抗弯性能

本文提出了理论和实验研究，以分析基于沙丘砂改变覆盖层厚度和配筋率的水泥砂浆加固钢筋混凝土梁的弯曲行为。在实验室中对梁试样进行适当的固化后，它们会承受渐进式载荷直至失效。得到的结果表明，加固梁的抗弯承载力约为134.44 KN，是1.2%的环境（过钢筋截面）配筋率下参考梁抗弯承载力的96%。然而，对于 0.5% 和 0.8% 的环境（欠钢筋截面），加固梁的弯曲峰值载荷和破坏载荷与参考梁的峰值载荷和破坏载荷相似。与参考梁相比，加强梁的偏转通常会减少。修复沙丘砂浆可用于提高沙丘砂浆加固受损钢筋混凝土梁的抗弯能力和延性。理论结果与从实验测试中获得的结果相比，在挠度和延展性方面，通常具有良好的一致性。