ABSTRACT

This study investigates the effect of using different amounts of superplasticizer (SP) (0.25% and 0.50%) on fresh and hardened properties, durability, ultrasonic pulse velocity (UPV) and thermal conductivity of two RCC pavements with cement contents of 12% (269 kg/m³) and 15% (325 kg/m³). The test results demonstrate that the use of 0.50% SP in RCC pavement containing 12% and 15% cement decreased Vebe time about 22% and 27%, respectively. Also, an increase in cement content from 12% to 15% decreased the Vebe time about 18%. With the use of 0.50% SP, the 28–day compressive strength for RCC pavements containing 12% and 15% cement increased by 9% and 14%, respectively. In addition, the use of 0.50 SP reduced the porosity of RCC pavement, to about 8% for RCC pavement with 12% cement and 4% for RCC pavement with 15% cement. The results demonstrated that using 0.5% SP increased the thermal conductivity of RCC pavements containing 12% and 15% cement around 19% and 7%, respectively. Generally, the UPV and Field Emission Scanning Electron Microscope (FESEM) test results showed that the use of SP in RCC pavement may lead to a denser structure.

摘要

本研究调查了使用不同量的减水剂 (SP) (0.25% 和 0.50%) 对两种水泥含量为 12% 的碾压混凝土路面的新鲜和硬化性能、耐久性、超声波脉冲速度 (UPV) 和热导率的影响 (269 kg/m ³ ) 和 15% (325 kg/m ³）。试验结果表明，在水泥含量为 12% 和 15% 的碾压混凝土路面中使用 0.50% SP 可分别减少约 22% 和 27% 的 Vebe 时间。此外，水泥含量从 12% 增加到 15% 会使 Vebe 时间减少约 18%。使用 0.50% SP 后，水泥含量为 12% 和 15% 的碾压混凝土路面的 28 天抗压强度分别提高了 9% 和 14%。此外，使用 0.50 SP 可降低 RCC 路面的孔隙率，水泥 12% 的 RCC 路面的孔隙率约为 8%，水泥 15% 的 RCC 路面的孔隙率约为 4%。结果表明，使用 0.5% SP 可使含 12% 和 15% 水泥的碾压混凝土路面的热导率分别提高 19% 和 7% 左右。一般来说，