Study On The Optimization Of Fine Aggregate Mixture Ratio Using Uniform Design And SMPSO

With the impetus of economic development, Water conservancy engineering hasdeveloped rapidly in recent years. At present, the annual output of nearly600million tonsof cement, of which around a third is used for mixing mortar, So every year more than1billion tons of cement mortar is needed. The national total output of concrete reached960million cubic meters in2010. Thus, the dosage of the sand which is an importantcomposition of mortar and concrete is very large every year.We know that the grading of sand will have a direct impact on the performance ofmortar. With large density of fine aggregate gradation theory as the foundation, this paperstudies how to optimize the fine aggregate grading, the sand of several different particlesize gradation are collocation according to certain proportion, to blending the sand of themaximum density. This paper mainly starts from two ways: One is theoretical research,high density gradation theory of sand are studied, combined with simplex micro particleswarm optimization algorithm, and big density of sand is got by optimizing thecombination. Another is study on the experiment, mixing of several kinds of gradation withthe formula of uniform design method, the bulk density of each group of mixed sand ismeasured, then the maximum packing density of sand is found and the effect of combinedhigh density of sand on properties of mortar is studied. On this basis, suitable for the sanddensity distribution formulas are derived by comparing the two ways of research results,and provides reference basis for mortar performance optimization design. This articlemainly has conducted the research in the following aspects:⑴This paper introduces several common experimental design methods, such ascomprehensive experiment, orthogonal design, object design, Latin square design anduniform design. According to their respective advantages and disadvantages, this paperadopts the method of uniform design to arrange test. But considering the coarse,combination, fine sand in genus formula experiment design problems, namely, the totalamount of sand including the volume of a coarse, medium and fine sand which restricteach other. Common uniform design method is not accurate enough, a formulation for theadvanced formula design method-uniform design was adopted in this paper. The basicprinciple of uniform design and the use of uniform design table method are introduced in this paper, test steps of uniform application formulation design and arrangement of threesand ratio are elaborated.⑵On the basis of consult literature at home and abroad, high density of aggregategradation theory of widely-used were summarized systematically, including: the Fullercurve, Taibo curve, I method, K method and particle interfering theory.⑶The basic principle and algorithm process of particle swarm optimization （PSO）are introduced. The parameters which influenced the optimization performance wereanalyzed. Then, an improved method——Simplex Particle Swarm Optimization Algorithm（SMPSO） is introduced in this paper. SMPSO not only has the same excellences asstandard PSO but also has the excellences in improving the ability in local searching androbustness of PSO effectively. And SMPSO can find the global optimum solution moreeasily than PSO. So SMPSO is an effective method in solving the multidimensional andcomplicated problems.⑷Combining with the test results of the uniform recipe design and Talbol theory,the influence of sand level matching to its compactness are analyzed, then the large densitydistribution curve of the sand is put forward, which is P=（d/D）^0.5A method forcalculating percent content of the particle material in the maximum density sandP=（d/D）^0.5combined with SMPSO is proposed.⑸The influence of the aggregate gradation and compactness of sand to theperformance of mortar are analyzed, and test experiment related to aggregate and mortarperformance was carried out. To research and analyze test results, the followingconclusions: with the increase of the density of the sand, the greater the mixing of slurrydensity and compressive strength, the better the resistance to CL-permeability andcarbonation resistance.⑹At the end of the paper, the whole research is summarized, deficiency is pointedout and the prospects to the further research are put forward.