超细石灰石粉对预应力孔道压浆料性能的影响

Influence of ultrafine limestone powder on the properties of pre-stressed duct grouting material

研究了不同掺量超细石灰石粉对预应力孔道压浆料工作性、力学性能、变形性能的影响,并通过XRD、SEM分析了石灰石粉的作用机理。结果表明:随着石灰石粉掺量的增加,压浆料浆体流动度先增大后减小,适宜掺量的石灰石粉对压浆料浆体流动度经时损失有较大改善;压浆料的抗压、抗折强度均随着石灰石粉掺量的增加呈现先增大后减小的趋势,最佳掺量为25%;石灰石粉能够降低压浆料的早期收缩;适宜掺量的石灰石粉对水泥的水化具有促进作用,提高了压浆料内部结构的密实度。

The effects of different contents of ultrafine limestone powder on the workability,mechanical properties,and deformation properties of pre-stressed duct grouting materials were studied,and the action mechanism of limestone powder was analyzed through XRD and SEM.The results show that with the increase of limestone powder content,the flowability of the pre-stressed duct grouting material first increases and then decreases.The appropriate content of limestone powder has a significant improvement on the loss of flowability of the pre-stressed duct grouting materials over time.The compressive and flexural strength of pre-stressed duct grouting materials show a trend of first increasing and then decreasing with the increase of limestone powder content,and the optimal content is 25%.Limestone powder can reduce the early shrinkage of pre-stressed duct grouting materials.The appropriate content of limestone powder has a promoting effect on the hydration of cement and improves the compactness of the internal structure of the pre-stressed duct grouting material.