掺尾矿高性能混凝土的制备

Preparation of High Performance Concrete with Iron Ore Tailings

研究了铁尾矿掺量、水胶比对高性能混凝土力学性能的影响,并采用XRD、SEM分析了尾矿高性能混凝土材料的水化硬化过程和微观结构。试验结果表明,最佳配比为采用尾矿62.5%、水淬矿渣16.25%、熟料16.25%和石膏5%,掺入占胶凝材料0.4%的PC高效减水剂,水胶比0.23,可以制备出高性能混凝土。该混凝土的水化初期主要是熟料矿物的水化,早期水化产物主要是钙矾石(AFt)、氢氧化钙(CH)和C-S-H凝胶;在水化反应的中后期,体系中钙矾石和C-S-H凝胶的协同生成能够促进体系强度的增长。养护28 d时抗折强度和抗压强度分别可以达到17.02 MPa和84.56 MPa,并且具有很好的力学稳定性。

The effects of tailings content, water-cement ratio on Huydration and hardening process of high performance concrete experiments indicate that, the best mixture ratio is the iron ore high-strength concrete is researched. by XRD and SEM is analyzed. The tailings 62.5% ,slag 16.25%, cement clinker 16.25%, gypsums 5%, PC super plasticizer dosage 0.4% and water-binder ratio 0.23. The early hydration of high performance concrete is mainly clinker hydration, hydration products are mainly ettringite, calcium hydroxide and C-S-H. In the middle and later age of the hardening process, the coordinated compressive growth of the ettringite and C-S-H gel is significant for the strength. The flexural strength and strength of iron tailings concrete can achieve 17.02 MPa and 84.56 MPa curing for 28d. And the concrete has good mechanical stability.