Experimental Research On Mechanics Strength Of Fly-ash Concrete

Coal-fired Power Generation is widely used all over the world. The effective utilization of the fly ash and bottom slag has been a worldwide topic. As the coal is one of the important energy in China, the wastes produced during the burning not only take up much land but also pollute environment. So the effective utilization of these wastes are gradually proposed the program.Nowadays, concrete is the most widely used building material. It is estimated the total consumption of the entire world every year is about 100 million tons. Such great amount, accompanying with the consumption caused during the producing and utilizing process and the pollution to the atmosphere and the environment has been concerned by the entire world. In order to protecting environment and energy and make sure the fly ash concrete's long-last utilize in civil engineering construction, the application of the fly ash concrete should be popularized in civil engineering. So the research about the strength of fly ash concrete has been carried on in this topic.By the orthogonal experimental design, the 7-day and 28-day compressive strength and flexural strength of the fly ash concrete is studied in this article. The following factors are considered in this study: the different content of fly ash, water-binder ratio and cementitious material content. Range analysis and variance analysis are applied to study the influence rules and significance of the above three factors to the strength of fly ash concrete. Excel is used to do the regression analysis, which include the following work: analysis of the linear relationships between the strength and the three factors, obtaining the linear relationships' regression equation and testing the reliability, three representative groups' experiment are chose for the extended experiment to study the high efficient water-reducer's influence on the strength of the fly ash concrete. There are two different methods to mix the superplasticizer with fly ash concrete. The first one is to keep the same water-binder ratio as the original orthogonal experiment but change the water and cementitious material content. The second one is to retain the same cementitious material content but change the water content and the water-binder ratio at the same time. The economic analysis about the different content of superlasticizer' influence on fly ash concrete is studied later in this passage. The optimum mix amount of fly ash in the concrete is obtained considering all the above analysis result.Finally, all researches in this article are concluded, some favorable conclusions are obtained and some questions need to be solved in future are pointed out.