一种有机外加剂对高含泥机制砂混凝土工作性及力学性能试验研究

研究了一种有机外加剂对高含泥机制砂混凝土的工作性及力学性能的影响。试验结果表明:提高减水剂中的保坍组分不能有效降低混凝土经时损失;提高缓凝组分有助于缓解混凝土经时损失,但其效果并不明显,且会明显增加混凝土凝结时间。通过掺入有机外加剂既可以显著降低高含泥机制砂混凝土的经时损失,又可以提高混凝土28 d抗压强度4%～10%,且对凝结时间影响较小,同时合理调整外加剂中的减水、保坍组分比例,更有利于发挥其作用效果。此外,该机制砂混凝土的耐久性还需进一步研究。

Experimental Study of a Type of Organic Admixture on Workability and Mechanical Performance of Artificial Sand Concrete with High Clay

The effect of an organic additive on the workability and mechanical properties of manufacture sand concrete with high clay content is mainly studied. The results show that the increase of water reducing agent cann’t effectively reduce concrete fluidity loss. The improvement of retarders is limited advantage to the workability of concrete, and it will obviously increase the setting time of the concrete. The addition of organic additive can not only significantly reduce the fluidity loss of concrete with high slag content of manufacture sand, but also increase the 28 d compressive strength of the concrete by 4%~10%, and has little effect on the setting time. At the same time, it is more beneficial to adjust the proportion of water reduction and slumping components in admixture. In addition, the durability of the mechanism of sand concrete with high content of clay needs further study.