水胶比矿渣粉对混凝土力学性能影响的试验及机理研究

Water/cement Ratio and Slag Powder Experiment and Echanism Study of Concrete Mechanics Performance Influence

以不同配比的水胶比和矿渣粉掺量为影响因素,配制混凝土试件进行抗压强度正交试验,深入系统的研究其对高性能混凝土力学性能的影响。在此基础上,通过电镜观测,从微观机理角度对宏观性能进行分析解释。研究表明,混凝土的抗压强度均随着水化龄期的延长而增大。水化早期,掺有矿渣粉的高性能混凝土强度都较低;水化后期,矿渣粉活性效应发挥显著。在水胶比不变时,随着矿渣粉掺量的增加混凝土的强度是在逐渐降低的。使用42.5R普通水泥,控制水胶比在0.40～0.20,掺加矿渣粉,可配制出C45～C65的高性能混凝土。微观机理研究显示矿渣粉的存在使混凝土中孔隙减少,孔径变小,结构变密实,起到了很好的填充和微集料作用。

Slag powder instead of cement mixing into concrete, has two aspects of technology and economic benefits. According to this char- acteristic, based on the different ratios of water/cement ratio and dosage of slag powder as influencing factors, concrete specimens for compressive strength of orthogonal test is prepared and thorough system to study the effect on the mechanical properties of high performance concrete.On this ba- sis, by electron microscopy （sem） observations, macro performance is analyzed from the Angl of microscopic mechanism explanation. Studies have shown that, the compressive strength of concrete increases with hydration time. In the early hydration, powder mixed with slag of high performance concrete strength is lower; late of hydration, slag powder active effects play a significant.The same water/cement ratio, with the increase of dosage of slag powder is in gradually reduce on the strength of the concrete. Use the 42.5 R P.O, Control water-binder ratio is 0.40 - 0.20, adding slag powder, to formulate the C45 - C65 high performance concrete.Microscopic mechanism studies demonstrated the presence of slag powder reduce pores in concrete, aperture small, become dense structure, played a very good fill and micro aggregate effect.