Study Of Activity On The Cement Adding High-volume Fly Ash

High degree utilizing industrial solid waste such as fly ash, slag, red mud and gangue in cement industry to make high performance cement products is attended by more and more people.But the existent reaserches and practice have proved that cement with high degree industrial solid waste is more sensitive to maintenance environment and has lower frost-resistance, larger self-constriction,quicker carbonization, especially when the content is large. These practical problems compel researchers to study the hydration and mechanism of cement-industrial solid waste system comprehensively, as well as the amount, composition and types of hydration product.So we can make reasonable application of the industrial waste if the shortcomings are eliminated.This paper focus on the fly ash-cement system and discusses the influence of fly ash dosage,water to binder ratio,curing temperature, chemi-excitation on mechanical property, non-evaporable water content and fly ash reaction degree detailedly. Experiment results show that:(1) The fly ash dosage is a main factor for fly ash-cement activity, If adding more fly ash, the compressive strength will be smaller, the non-evaporable water content will be less, and the fly ash reaction degree will be lower.(2) Water to binder ratio has obvious influence on the compressive strength of fly ash-cement,the best ratio is0.4.(3) Increasing the curing temperature can improve the compressive strength and aggrandize non-evaporable water content and the reaction degree of fly ash.(4) Sodium hydroxide and sodium sulfate has the best activation effect. When the fly ash dosage is40%,the highest compressive strength in ld,3d,and7d can respectively reach12.57MPa,16.48MPa and22.96MPa (the dosage of sodium hydroxide and sodium sulfate is1%).When the fly ash dosage is80%,the highest compressive strength in1d,3d,and7d can respectively reach4.86MPa,8.2MPa and10.87MPa (the dosage of sodium hydroxide and sodium sulfate is1%).