高强度低黏度注浆材料配比试验研究

为满足微裂隙岩体注浆加固要求，需研究一种强度高、黏度低的高性能注浆材料。选用超细水泥、硅粉、超细粉煤灰、聚羧酸系减水剂为原料，结合单因素试验和正交试验，对浆液进行改性。试验结果表明：在水泥中掺加4%～12%的硅粉，浆液的结石体强度可以提高8%～34%|用超细粉煤灰替代一定量的水泥，可以降低浆液的黏度，当粉煤灰替代量超过20%后，浆液黏度不再降低，达到作用极限值|聚羧酸系减水剂对于降低水泥浆液的黏度有着显著效果，掺加0.1%～0.5%的减水剂，浆液的黏度可以降低25%～90.6%，减水剂掺量越高，浆液析水率越大，浆液越不稳定|当水灰比为0.8、硅粉掺量为10%、粉煤灰代替量为20%、减水剂掺量为0.3%时配置的浆液性能最优，新型浆液结石体28d抗压强度为22.98MPa，比纯水泥浆液结石体的抗压强度提高13.6%，黏度为21.83s，比纯水泥浆液黏度降低89%。

Experimental study on the ratio of high strength and low viscosity grouting materials

In order to meet the requirements of grouting reinforcement in micro-fractured rock mass, a kind of high performance grouting material with high strength and low viscosity should be studied. Ultrafine cement, silicon powder, ultrafine fly ash and polycarboxylate superplasticizer were selected as raw materials. The slurry was modified by single factor test and orthogonal test. The results show that the stone strength of slurry can be increased by 8% ~ 34% by adding 4% ~ 12% silica powder in cement. Replacing a certain amount of cement with ultra-fine fly ash can reduce the viscosity of slurry. When the amount of fly ash is more than 20%, the viscosity of slurry will no longer decrease, reaching the limit of action. Polycarboxylate superplasticizer has a significant effect on reducing the viscosity of cement slurry, adding 0.1% ~ 0.5% superplasticizer, the viscosity of slurry can be reduced by 25% ~ 90.6%, the higher the amount of superplasticizer, the higher the water out rate of slurry, the more unstable the slurry. When the water-cement ratio is 0.8, the silicon powder content is 10%, the fly ash replacement amount is 20%, and the water-reducing agent content is 0.3%, the slurry performance is the best. The compressive strength of the stone body of the new type slurry is 22.98 Mpa on 28 d, which is 13.6% higher than that of the stone body of pure cement slurry, and the viscosity is 21.8 s, which is 89% lower than that of pure cement slurry.