Of Cfg Pile Material And Its Resistance To Sulfate Attack Study

This paper, combining the characters and engineering application of the CFG (cement fly ash gravel) and its present research condition overseas and at home, studies the preparation of CFG pile body technique and its erosion resistance under sulfate environment.On the basis of the further research of the influence rules of water-binder ratio, powder-ash ratio, quantity of cementitious materials, coarse aggregates, stone-chip ratio, etc. and mixing proportion on the mechanical properties, working performance of the CFG pile body, the paper puts forwards the design method of proportioning parameters of CFG pile body materials and manages to prepare the materials of CFG pile body of different strength levels. Under this basis, through simulating the erosion of sulfate underground water, the experiment researches the resistance ability to erosion under sulfate environment.The experiment result shows that:1) Water-binder ratio, powder-ash ratio, quantity of cementitious materials and such parameters significantly influence the strength, modulus of elasticity of the CFG pile body materials. The higher water-binder ratio, powder-ash ratio and more quantity of cementitious materials are used, the lower strength of the CFG pile body materials and modulus of the elasticity will be. And with the increasing curing period, the strength and modulus of the elasticity of the CFG pile body materials increase steadily.2) The more volume fraction of aggregate is, the higher modulus of elasticity under static compression will be.3) The higher water-binder ratio is, the more penetrability and porosity will be. There is an optimal powder-ash ratio that produces the lowest penetrability and porosity.4) Compared with the specimens of the CFG pile body materials in water, the strength of those in sulfate solutions shows an increasing tendency. And under circumstance of this experiment, there is no expansion break of the specimens.5) The specimens are heavier in sulfate solutions; their dynamic elastic modulus increase with the growing immersion period, too. CFG pile body materials have good resistance ability to erosion under sulfate environment.