This study shows the mechanical properties of lightweight concrete (LWC) made by partially replacing ordinary Portland cement (OPC) with class F fly ash (FFA). Natural sand and pumice were used as the fine aggregate and coarse aggregate, respectively. Five LWC mixtures, M1, M2, M3, M4, and M5, were made by replacing, by weight, of 0%, 10%, 20%, 30 %, and 40% OPC with FFA, respectively. The mix proportion of LWC, by weight, was 1.00 binder: 3.24 fine aggregate: 1.19 coarse aggregate, and the water-binder ratio was 0.32. Tests of the LWC mechanical properties were conducted at the hydration time of 28 and 56 days using 150 by 300 mm cylindrical specimens. The results indicate that the use of FFA as a partial replacement for OPC improved the development of the mechanical properties of LWC. The compressive strength and the modulus of elasticity of the LWC increased in all the mixtures during the hydration time. The optimal proportion of FFA for replacing OPC in LWC is about 20%. With this optimal proportion and after 56 days of hydration, the compressive strength and the modulus of elasticity are, respectively, about 113% and 105% of those produced by LWC made with 100% OPC.

本研究显示了用 F 级粉煤灰 (FFA) 部分替代普通波特兰水泥 (OPC) 制成的轻质混凝土 (LWC) 的力学性能。天然砂和浮石分别用作细骨料和粗骨料。五种 LWC 混合物，M1、M2、M3、M4 和 M5，分别通过用 FFA 代替按重量计 0%、10%、20%、30% 和 40% 的 OPC 制成。LWC的配合比为1.00粘结剂：3.24细骨料：1.19粗骨料，水胶比为0.32。使用 150 x 300 mm 的圆柱形试样在 28 天和 56 天的水合时间下进行 LWC 机械性能测试。结果表明，使用 FFA 作为 OPC 的部分替代品改善了 LWC 机械性能的发展。LWC的抗压强度和弹性模量在水化期间在所有混合物中增加。LWC 中替代 OPC 的 FFA 的最佳比例约为 20%。在这个最佳比例下，经过 56 天的水化后，其抗压强度和弹性模量分别约为 100% OPC 制成的 LWC 的 113% 和 105%。