Study On Correlation Of Gangue-cement System Particle Size Distribution And Its Performance

Coal gangue is industrial solid residues that are discharged when coal isexcavated and washed in the production course of coal mine, and is one of the mostindustrial solid castoffs in our country. In order to solve the heavy burden of thesociety, environment and resource which is caused by the huge industrial wasteresidue; applying the industrial waste residue into the cement fields is an effectivemethod. In this thesis, the author begins the subject with the problem of currentadmixture cement, points that grain grade problem is one of the reasons why theperformance guideline of some admixture cement is not so perfect.In this research, the author employs milled inert adulterated material to replacethe same quantity of coal gangue, and then to study the influence to performanceparameter of cement which is caused by coal gangue. Besides that, some modemtesting methods, such as XRD, SEM and XRF have been used to study the cementhydration and performance of different particle mixed with coal gangue. With theresult, in expectation that it can offer some reference to optimized design of coalgangue-cement system particle size distribution.From the study it's showed that: in the coal gangue cement system, reasonablegrain grade plays a very important role in the coal gangue cement hydration andperformance; the coal gangue and cement particle with different size range will havedifferent effect to system hydration and performance; the matching of coal gangueand cement particle is also very important to cement performance; the D₅₀ of coalgangue in cement system is 7～13μm, coal gangue is very thin (D_50-is 3～9μm), theintensity advantage of this range mostly root in the distribution of cement particlephysical effect in the coal gangue-cement system. When the D₅₀ is less then 7μm,the source of intensity can be considered as the result of chemistry.This thesis has done an analysis on the experiment result with grey theory, hasdivided coal gangue into five particle level:＜5μm,5～16μm,16～32μm,32～50μm,50～80μm; and then built a GM (1,5) grey theory model with the followingcharacteristic factors-compressive strength and plasm rheologic property. In this case, we can forecast the strength of the admixtures cement quickly by learning thedistributing of admixture particles, or we can mix admixture material withcorresponding particle size distribution into the cement to get the very strength weneed.