Panzhihua Iron And Steel Blast Furnace Slag Foundation Soil Properties And Thermal Physical Properties Of The Pilot Study

This graduate dissertation is based on the research of the trail engineering assembly line of producing carbonized blast-furnace slag under the condition of blast-furnace's high temperature at Panzhihua Iron and Steel Co. Cementing BF slag samples found at the groundsill of the slag field were studied by means of comprehensive and scientific experimental research measures including:soil mechanics, heat transfer, material science and mineralogy. The thermo-field of the foundation soil of the construction site was made clear and the microstructure, mineral component, the characteristics of the foundation soil, hardness (considering effect of the temperature), and thermal properties of the cementing BF slag were experimented and studied.The results and achievements of the research are as follows:1. Cementing BF slag is similar to porous solid materials, which is not suitable to be assessed by granule soil criterion. Therefore, the methodology of experiments needs to be adjusted.2. Water affects the cementing BF slag in terms of hydration reaction, during which process, the swell rate, bulging force and contractility tend to be small.3. The slag remains active and it is likely to undergo the process of hydration. Therefore, the reaction heat contributes to the heat source of the foundation soil.4. The slag possesses a certain amount of compressive stress and the statistics got at different locations was different.5. The coefficient of heat expansibility is close to or is smaller than that of the cement. Because of the high elastic moulds of the slat, the thermal stress produced by the variation of temperature is never to be neglected.6. Cementing BF slag is under the influence of efflorescing process. Both physical and chemical effloresce cast influence on the physical mechanic properties.7. The experiments on sulfur trioxide, chlorine ion, temperature measuring at the site and PH value tests show that cementing BF slag environment has little influence on the maintenance and endurance of cement.Comparing with other studies on slag foundation soil, the dissertation concludes that the microstructure of cementing BF slag is similar to that of the porous solid materials. The inner heat source of the slag layer temperature field comes from the chemical reaction of the cementing BF slag. In conclusion, some of the civil engineering experimental methods presently used on measuring the parameter of the cementing BF slag need to be adjusted.