Experimental Research On Rigid Pile Composite Foundation Composed Of Coal Gangue Concrete

On the direction of solidified principle and technique of flyash, a kind of fiyash-lime-excitant composite cementing material, which has bounding capacity in normal temperature and pressure, is tried to be made according to principle of clink-free cement. Taking coal gangue as coarse-to-fine aggregate to make coal gangue concrete that would be vertical strengthen body of composite foundation, the engineering application possibility of it is explored by simulation experiment.On the condition of laboratory, experiment on cementing material of fiyash-lime-excitant and gangue-lime-gypsum are carried out. In addition, experiment on composite triaxial sample composed of gangue cylinder core strengthen and clay shell and gangue concrete strengthen are also completed.The experimental results show that flyash can be excited by excitant on the condition of alkalinity, and can coagulated and hardened by the action of water. Flyash can be made into cementing material by proper design of mixture ratio. The results also show that high calcium flyash has more trass characteristic than low one. The calcined gangue can has higher activity after milling, and can have higher bounding strength with the action of lime- gypsum-concrete composite excitant, and it can be replacement of cement-gangue concrete.From above experimental results, we can draw an conclusion that crushed gangue after proper graded can be used in composite foundation of disperse material pile; super crushed gangue can be used as non-clinker cement, and be used in composite foundation of flexible material pile; non-clinker cement gangue concrete compounded by super crushed gangue cementing material and gangue aggregation, can be used as a kind of cement in composite foundation of rigid material pile.The triaxial experiments on gangue composite sample were carried to simulateinsitu testings.It is testified that gangue disherse hiles shere the load together and harmonize to settler with soil. The triaxial experiment on gangue concrete pile shows that the gangue concrete has the same characteristic as the common concrete and can be used in composite foundation of rigid pile.Because the limitation of experimental condition and experimental content, the results can not completely reflect active rule and reactive mechanism of flyash and gangue.But the phenomena disclosured by this tests will be helpful for the application of flyash and gangue, and be useful for promotional application of industry waste slag like flyash and gangue in composite foundation.