【摘要】 通过偏高岭土和硅灰分别与粉煤灰双掺,使用机制砂混凝土调节剂,在机制砂级配不良,胶材用量仅为500 kg/m~3,水胶比高达0.33的情况下配制出C80高强机制砂混凝土,并研究了调节剂、细集料类型、偏高岭土掺量、硅灰掺量对机制砂混凝土工作性及力学性能的影响。试验结果表明,适量调节剂可改善机制砂混凝土的工作性,并提高其抗压强度;机制砂对混凝土的工作性有不利影响,但对其劈裂抗拉强度和抗折强度均有所提高;偏高岭土和硅灰对机制砂混凝土的工作性及力学性能影响显著,随着其掺量的增加,机制砂混凝土的包裹性、和易性提高,而坍落度、扩展度、流动性减小,抗压强度、劈裂抗拉强度和抗折强度呈现先增大后减小的趋势。更多还原

【Abstract】 C80 high strength manufactured sand concrete was prepared by mixing metakaolin and silica fume with fly ash separately, supplemented with the use of manufactured sand concrete regulator. The concrete sand used in the concrete was poorly graded, and the amount of cementing material was only 500 kg/m~3, and the water to binder ratio was as high as 0.33. The effects of regulator, fine aggregate type, metakaolin content and silica fume content on the workability and mechanical properties of manufactured sand concrete were also studied. The results show that a proper amount of regulator improves the workability and compressive strength of manufactured sand concrete. Manufactured sand has an adverse effect on the workability of concrete, but it is beneficial to the splitting tensile strength and flexural strength of concrete. Metakaolin and silica fume have significant effects on the workability and mechanical properties of manufactured sand concrete. As the amount of admixture increases, the encapsulation and workability of manufactured sand concrete increase, while the slump, spread, and fluidity decrease, and the strength tends to increase first and then decrease.更多还原