The Research And Application Of Mineral Powder On The Performance Of C80 High Performance Concrete

With the development and application of C80 and above with high performance concrete technology,the researchers found that fine particles of mineral powder can effectively fill the micro pores inside the cement gel,in the use of superplasticizer can improve the rheological properties of concrete.At the same time,improve the strength and durability of concrete mixed.By mineral powder by filling the voids of cementitious materials,improve the particle size distribution,the concrete internal structure more closely;to play the ball effects of mineral powder,improve the performance of concrete mixture,such as the lower cohesiveness),improve the high strength grade of concrete pumpability,reduces the construction difficulty;mineral powder of secondary hydration reaction can increase the later strength of C80 concrete,while improving the frost resistance durability.The test for C80 high performance concrete materials of cement particle size below mineral powder with cement particle gradation were studied by changing the mineral powder added into the categories and dosage of cement of grade of mineral powder pairing low water binder ratio the influence of cement-based composite cementitious slurry rheology properties and hardened properties,and single doped silica fume and ultra-fine fly ash compared,single doped superfine powder can the cementitious material with higher early and late compressive strength value is obtained.Double doped superfine powder and superfine powder ash can get high long-term strength value,by different cementitious material system of each instar stage compressive strength value comparison shows,three mixing mineral powder,silica fume replacement of 3%,ultra-fine powder instead of 3%,superfine fly ash instead of 4%,replace the amount to 10%of the 56 days cement mortar compressive strength is the highest.The content of fine powder can be optimized and added with the cumulative penetration rate of 3?32 m interval particles,which makes the cement based cementitious material system obtain good workability and compressive strength.Superfine powder and ultra-fine fly ash doped double substituted cementitious material system for optimal and reached best mortar fluidity of cement replacement rate is 13%.The workability,strength and frost resistance of concrete with C80 concrete mixture ratio of single and double and three mineral powder were determined,and the effect of particle size of mineral admixture on the above three properties was analyzed.The 56d compressive strength of C80 concrete is higher than the reference value after the addition of mineral powder.Three the effect of the mineral powder on the compressive strength of C80 is more obvious.Comprehensive test data,select the best C80 mix proportioning scheme,applied to the engineering practice,and the actual engineering of C80 concrete quality control,concrete work,concrete strength and concrete frost resistance of concrete description and analysis.Value considering the workability,compressive strength,frost resistance and give consideration to economy,and ultimately determine the preparation of C80 concrete with mineral powder the best mixing ratio for ultrafine slag replacement of 3%and 10%superfine fly ash to replace,confecting C80 concrete expansion to 680mm,slump reached 265mm and 56d compression strength reached 102.7MPa and frost resistance grades F400.Will best fit than used in practical engineering,the expansion of C80 concrete degree reached 660 mm,slump 240mm,56d compression strength reached 94.2MPa,frost resistance grade for F400 and meet the engineering construction and use requirements.