Research On The Hydration And Properties Of Particle-Size-Distribution Cement

This thesis studies the influence of grading effects of mineral particles, and theoretically analyzes the improvements which the fine mineral powder could give to the duality or tri-variate systems. It is tried to summarize the relationship between the dense packing property and so factors, such as percentage, fineness or the particle size distribution of those mineral powders. Then, through some experiments, the influences of the fine mineral powders on the fluidity, rheological and hardened properties and the hydration are studied. The tests of standard using water ratio can reflect the existence of the dense packing phenomenon directly,First, calculated the Particle-Size-Distribution of multi-powders based the dense packed Andreasen equation, then, calculated the packing density based Aim and Goff model. Based upon those observations and data from literatures, we choose two different systems to lucubrate, contemporary, we added some correlation systems. Experimental studies are carried out on the rheological properties of fresh pastes as well as the strength of harden paste, validated the dense packing density through water requirement ratio of normal consistency, the result indicated water requirement ratio of normal consistency can be a value to text the packing density. Finally, we discussed the hydration process of Particle-Size-Distribution cement.The studies have shown that: The Aim and Goff model can get the packing density of mineral powder-cement system conveniently; the distribution of cement and mineral powder has important effect on packing density of mixtures, the better distribution, the higher packing density; particle distribution is closely relevant to fluidity characteristics of fresh pastes, under identical condition , the yielding shear stress and plastic viscosity reduce with increasingly better particle distribution and thus higher packing density of mixture; particle distribution is also closely relevant to the strength of hardened pastes since for better particle distribution, the packing structure of Particle-Size-Distribution cement is more close, which can improve not only the strength but also the resistance chloride diffusion; the effect of Particle-Size-Distribution cement also can find from...