Research On Application Technology Of High Titanium Bearing BF Slag Concrete

At the present time, there doesn't has any technology which could recovery titanium from high titanium-bearing BF slag and make full use of the residue at the same time, even implements industrial production. Therefore, using the high titanium-bearing BF slag as the building materials is a major route for Panzhihua Iron & Steel Co.. Presently, the research of using BF slag in the building materials isn't enough. This thesis study on the feasibility of using high titanium-bearing BF slag substitute for the natural sandstones as the concrete aggregate. On the basis of previous work, C10~C55 of common concrete and C20~C60 of pump concrete are produced by this slag as the concrete aggregate according to the state's existing design norm of concrete mixture ratio. The physical and mechanical properties, durability and rebound regularity of concrete have been studyed systematically. The main conclusions are listed as follows:Under the condition of hydro-thermal, the largest linear expansion rate of slag concrete is 123×10-6mm/m without bursting, so the problem of volume variable does not exist. The alkali-aggregate reaction of slag aggregate indicates that the largest linear expansion rate of samples is 0.046% which is far less than the national standards 0.10%. Durability can be satisfied with the requirements of relevant national rules.When the slump constant and the amount of cementitious materials are the same, the intensity of slag concrete of 28days and 60days are much higher than that of natural sandstone concrete. The slag concrete and the natural sandstone concrete have the same Young's modulus.The grade of impervious of C20 slag concrete is P8. The depth of carbonization is 0.2 mm. The diffusion coefficion of Cl- is 1.421×10-12 m2/s. The flexure coefficient after corrosion by sulphate is 0.97. The grade of frost resistance is F100. All of these factors meet the requirements of the durability design of concrete.The special rebound strength curve of high titanium BF slag and the rebound strength curve of the area of PanZhihua has significant difference. It is better to use the special rebound strength curve in the safety evaluation of actual construction to assure the safety of the building structure.