高强度水泥基灌浆料基本力学性能正交试验研究

Orthogonal test study on basic mechanical properties of high strength cement-based grouting material

选用32. 5R复合硅酸盐水泥作为主要胶凝材料,通过正交试验,研究了水胶比、胶砂比、粉煤灰、硅灰、膨胀剂和减水剂对水泥基灌浆料基本力学性能的影响,涉及到的主要性能指标为灌浆料的初始和30min流动度、7d和28d抗压及抗折强度。试验结果表明:水胶比和胶砂比对水泥基灌浆料的综合性能影响最为显著,减水剂的影响作用较小;粉煤灰、硅灰对其流动度及28d强度影响较大;膨胀剂对其7d强度影响较大,尤其是抗折强度,对其他性能的影响不显著;以水泥基灌浆料28d高强度为目标,较大流动度为条件,得到优化的最佳因素水平组合为A2B2C1D3E2F2,即水胶比为0. 34、胶砂比为1∶1. 2、粉煤灰掺量为15%、硅灰掺量为8%、膨胀剂掺量为10%、减水剂掺量为1. 00%。

The 32. 5 R composite Portland cement was selected as the main cementitious material. The influences of ratio of water-to-binder ratio,mortar-to-cement ratio,fly ash,silica fume,expansion agent and water reducing agent on basic mechanical properties of cement-based grouting material were studied by orthogonal test. The main performance indicators involved were the initial and 30 min fluidity of the grouting material,the 7 d and 28 d compressive and flexural strengths.The test results show that the water-to-binder ratio and mortar-to-cement ratio have the most significant effect on the comprehensive performance of cement-based grouting material,and the effect of water reducing agent is smaller;fly ash and silica fume have greater influence on fluidity and 28 d strength;the water reducing agent has a great influence on the 7 d strength,especially the flexural strength,and its effect on other properties is not significant;with the 28 d high strength of cement-based grouting material as the target and the large fluidity as the condition,the optimal combination of the best factors is A2 B2 C1 D3 E2 F2,that is,the water-to-binder ratio is 0. 34,the mortar-to-cement ratio is 1 ∶1. 2,and the fly ash content is 15%,the amount of silica fume is 8%,the amount of expansion agent is 10%,and the amount of water reducing agent is 1. 00%.