The Effect Of Supplementary Cementitiou Materials On The Formation Of Cement Paste Microstructure And Mechanical Properties

Supplementary cementitious materials mixed with cement has nearly a hundred years of history, most study on them stay in the interpretation of experimental phenomena because of insufficient depth study and lack of holistic and systematic, but the preparation and utilization of various effects of supplementary cementitious materials, improve cement-based materials Performance, still need to be deeper study.In this paper, through studying the effect of the formation of cement paste microstructure and macroscopic on the supplementary cementitious materials, explore the mechanism of different types supplementary cementitious materials in cement, provide theoretical guidance for rational use and deal with supplementary cementitious materials, so as to comprehensively improve the performance of cement-based materials and achieve the sustainable development of cement industry. This paper carries out a detailed study from the following:1. Discuss the effect of pore structure of cement-based material on supplementary cementitious material. The effect of cement paste pore on supplementary cementitious materials with different content (porosity, pore volume, pore surface area, average pore diameter, pore size distribution, pore volume fractal dimension), the results showed that supplementary cementitious materials holes of different parameters on the impact of different content, the appropriate dosage can significantly improve the pore structure.2. Discuss the effect of mechanical properties of cement-based material on supplementary cementitious and the relationship between pore structure and mechanical propertied. The early strength declines when mixed supplementary cementitious materials, but it can catch up with even more than pure cement strength after 28 days. The strength was more than pure cement after 90 days. It's more intuitive and scientific to use activity factor evaluation method to evaluate the enhancement of supplementary. Using the limit porosity and Balshim regression formula, the ultimate strength of majority of systems are the range 75 ~ 95Mpa. The ultimate strength of the systems mixed supplementary cementitious materials are more than the ultimate strength of pure concrete, increasing with the content of supplementary cementitious materials.3. Discuss the effect of hydration products of the composite system and the impact of combined water on supplementary cementitious material. For the combination of hydration water, it decrease with the increase of content of slag, coal gangue, fly ash; incorporation of slag will be reduced at an early stage, but higher than the pure cement after 28 days, increasing with content. Analysis on CH on the amount of hydration products and hydration in the post-secondary binder CH factor, it showed that the absorption of CH slag strongest, second by fly ash, coal gangue worst. The number of less than 200? pores in Hydration products have a good linear correlation with amount of gel water, so that can be considered pore of less than 200? are micropore areas and compressive strength of the composite system and flexural strength increased linearly with the increase of the total combined water...