水泥细度对水泥砂浆抗冻性能的影响研究

Study on the Effect of Cement Fineness on the Freeze Resistance of Cement Mortar

为研究水泥细度对水泥砂浆抗冻性能的影响,对3种不同水泥细度的水泥砂浆试件进行了抗冻性试验,对比分析水泥细度对水泥砂浆抗压强度、电阻率演化特性的影响规律,建立了相应的冻融损伤模型。结果表明:适当增加水泥细度可以提高砂浆的抗冻耐久性,过度提高水泥细度对抗冻性的提高没有帮助,不同水泥细度的砂浆抗压强度大致呈指数衰减。砂浆的冻融破坏是由表及里逐渐加大的一个过程,不同深度的电阻率与冻融次数间的也是呈指数衰减。

In order to study the effect of cement fineness on the freeze resistance of mortar,three kinds of cement mortar specimens with different cement fineness are tested for freeze resistance,and the effects of cement fineness on the compressive strength and resistivity evolution of cement mortar are compared and analyzed.Based on test results,the corresponding freezing-thawing damage model is established.The results show that an appropriate increase in cement fineness can improve the freeze resistance of the mortar,but excessive increase of cement fineness cannot help to further improve the freeze resistance.The compressive strength of mortars with different cement finenesses roughly decreases exponentially.The freezing-thawing damage of mortar is a process that gradually increases from the surface to the inside,and the resistivity at different depths and the number of freezing-thawing cycles also decay exponentially.