| The concrete is the most important building material, as a wide kind of the useful construct material. However as main raw material of concrete, Portland cement is confronted with new challenges. Although Portland cement have the advantages such as a source of raw materials and its technology is mature, existent shortcomings such as natural resources consumption lost, energy consumption height, the environment contaminating, etc. It is necessary to probe new environment-protected, source-saved materials.In this thesis, on the base of the physical and chemical performance of gangue and fly ash, AAM (alkali-activated material) and its products were made up of gangue or fly ash, and ordinary silicate, and divalent metal calcium salt. The results show that the new cement has high strengther and better duration. The effect of raw material, process flow, and technological parameter on this raw material has been investigated. The feasibility of this new cement in the construction and ocean-engineering was also studtied. The hydration products of AAM and its morphology, microstructure were observed by using equipment as XRD and SEM etc. The mechanism of hydration and hardening of AAM was discussed . The main conclusions were shown as follows:(1) The strength of AAM is low by only the clinker and activator. The strength was greatly increase by the addivantage of Portland. The new type 32.5 AAM (alkali-activated material) had been achieved with 35% clinker and 65% combustion gangue and alkali-activator, while 42.5 AAM cement can also been acheved with 50%~60% clinker, 40~50% fly ash and alkali- activator, which can save a lot of the natural resources and energy sources in cement production. It is also favorable for improving environment, and is significant for development of cement industry.(2) It had been discussed that the concrete's effectuation of cement and fly ash in different component addition, different activator and addition, different water-cement ratio condition in the cement-fly ash mixed cementitious system through the orthogonal experiment. The results show that the optinum the cement-fly ash mixed cementitious system composed of 40% fly ash, 54.8% cement, 1.2%activator-1 and 4%activator-2. Tthe reasonable workability, and strength of AAM affter 28 days were comparable to that of Portland cement.(3) With the discussing the physical and chemical performance of two kinds of gangue, the activity is optimal when two kinds of gangue had been set at 600℃for 2 hours. There are three schemes, including difrent ratio of NaOH and Na2SiO3, different activator addition and water-reducing agent by using 35% the clinker, 65% combustion gangue. The new type 32.5 AAM can be produced with 35% clinker and 65% combustion gangue, 2% alkali-activator (NaOH / Na2SiO3=2/1) and 0.3% water-reducing agent.(4) Technology process had been designed about manufacture of the cement-combustion gangue, and the cost of manufacture is figured out . Alkali-activated material can be producted, using vertical kiln cement produces handicraft. And comparing with manufacture of Ordinary Portland Cement, it has several advantages as follows, simpler technology, less in vest, lower cost, less consume of energy and so on. So it is a green, environment-protected, source-saved, prospect-developed construction material.
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