| The hydrated calcium silicate powder with poor crystal, extremely larger specific surface area and particle size of around 40 nm was manufactured by using dynamic autoclaved technology with designed autoclaved schedules, diatomaceous earth and fly ash as the siliceous materials and the lime as calcium material. The affect of raw materials, C/S, autoclaved schedules on the properties of manufactured products was investigated, and the feature, particle size and properties of hydrated calcium silicate powder was measured with XRD, Nitrogen absorption, SEM, TEM, DSC etc. measurement technology. The bulk samples with high strength and water-resistance were manufactured by pressuring the hydrated silicates powder based on the mechanism of the non-stable minerals with gaining strength by contacting each other. The affect of pressure load and maintaining load period on the mechanical properties and water-resistance of this bulk samples was investigated. The solution painting with excellent properties were gained by replacing the filler in normal painting with the hydrated silicate powder, and the mechanism of improvement of properties was explored.The autoclaved hydrated silicate is another primary building materials next to cement and concrete. However, the composition of traditional autoclaved hydrated silicate primarily includes the Tobermorite, Xonotlite and Hydrogarnet which are good crystals, therefore manufacture of such materials consummated more energy and the products have the limited functions. In this thesis the focus is on the hydrated silicates with poor crystal , larger specific surface area and fine particle with nm order size and its manufacture technology and using industrial waster as raw material. This study will provide the guidance to expanding the application of the autoclaved silicate while it is prospective to improve the production technology of the traditional silicates.Results and conclusion of this thesis:manufacture of the hydrated silicate powder with nm order sizeThe hydrated silicate powder with nm-order size, very large specific surface area and poor crystal was manufactured by using dynamically autoclaved technology and diatomaceous earth and fly ash as the siliceous materials and the lime as calcium material. This powder consist of the particle of 40 nm diameter and these fine particle piles, contacts and combines each other by observing with TEM. The production processes include: pre-treatment of raw material, mixing, autoclaving, filtering, drying. The production technology is simple and easily operating and is applied in industry.The study found that the manufactured powders have the greatest specific surface area 57.5m2/g (from diatomaceous earth) and 104.7 m2/g (from fly ash), the greatest porosity 0.2ml/g and 0.3ml/g, the optimized pore radius 0.85nm and 0.87nm respectively when C/S =1, maintaining temperature = 120℃ and marinating temperature period = 7hrs. The observation with SEM and TEM found that the autoclaved reaction processed completely and the particles size of products are most same. The conclusion is that the optimized autoclaved schedule: maintaining temperature = 120℃, maintaining temperature period = 7 – 10 hrs when C/S =1.The mechanism of autoclaving reaction of calcium and silica material primarily solution-deposit reaction based on various observation and measure of microstructure. The primary products includes hydrated calcium silicates with irregular, poor crystal. The average chemical composition is Ca1.59SiAl0.298O1.088 (from diatomaceous earth) and Ca0.271Mg0.140SiAl1.273Fe0.127O1.840 (from fly ash)Cementitious properties of hydrated silicate powder with nm-order sizeThe bulk samples made from the hydrated silicate powder with poor crystal and nm-order size by pressure have the strength and water-resistance with any curing. This result provides the evidence that this powder indeed have Cementitious property under the pressure as the bond between particles primarily depend on the very large specific surface area, that is, the form...
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