盾构废弃泥沙再生制备高性能注浆材料的试验研究

Experimental Study on Preparation of High Performance Grouting Material from Waste Sand of Shield Tunnel Construction

利用盾构施工产生的废弃泥沙与水泥复合制备了一种高性能环保型注浆材料。研究了水固比、砂胶比、减水剂掺量对注浆料稠度、流动度、凝结时间、结石率、泌水率、抗压强度等性能的影响。结果表明:随着水固比增大,注浆料的初始稠度、凝结时间、流动度均增大,而结石率、抗压强度下降。随着砂胶比增大,注浆料的初始稠度、流动度均减小,而凝结时间延长。掺入聚羧酸高性能减水剂后,注浆料的工作性能显著提升。优选的配合比为:水固比0.45,砂胶比3∶1,减水剂掺量2‰。相应注浆材料的技术指标为:流动度164 mm,初始稠度118 mm,凝结时间1035min,结石率95.7%,泌水率2.4%,3 d抗压强度12.0 MPa。

In this study, a high-performance environmentally friendly grouting materials was prepared by using waste sand generated during shield tunnel construction. The effects of water-solid ratio, sand-gel ratio and water-reducing agent dosage on grouting material consistency, fluidity, setting time, stone rate, drainage rate and compressive strength were studied. The results show that the initial consistency, setting time and fluidity of the grouting materials increase with the increase of the water-solid ratio, while the stone rate and compressive strength decrease. With the increase of the cement-sand ratio, the initial consistency and fluidity decrease, while the setting time increases. By adding water-reducing agent,the working performance of grouting material is significantly improved. In this test, the optimal mix ratio is: water-solid ratio 0.45, sanding ratio 3∶1, and water-reducing agent content 2‰. The technical indexes of corresponding grouting materials are fluidity of 164 mm, initial consistency of118 mm, setting time of 1 035 min, stone rate of 95.7%, bleeding rate of 2.4% and 3 d compressive strength of 12.0 MPa.