关键词: 机械振筛机, 风成沙, 筛析法, 最佳筛析时间

Abstract: The sieve analysis is a usual method for the classification of particle fractions, and the mechanical sieve shaker is widely used for sieve analysis. However, there are few studies on the optimum time of different kinds of particle matters sieved by use of mechanical sieve shaker. In this paper, aeolian sand was selected as the experimental sample, and knockout vibrating sieve machine and a set of standard sieves at intervals of 1/2Φ were used and the sieving time was set as a variate in this test. The results showed that with the increase of sieving time, although the numbers of the parameters of mean grain size and sorting are increased and presented a stablized trend, the parameter level has not changed. Some individual parameters of skewness and kurtosis are changed with the sieving time, but the majority remain a same standard; Totally, the sieves whose mesh numbers are more than 35 are the main sieves which decide the optimum time of the set of standard sieves at intervals of 1/2Φ, but the optimum times of the different sieves for the different aeolian sand samples are different. In order to ensure the level of grain size parameters no longer changed, and the weight of sand on all sieves changed a little or tended to be stable, this paper selected the average of optimum time of all samples, and 14 min was suggested to be the optimum time of sieving aeolian sand.

Key words: mechanical sieve shaker, aeolian sand, sieve analysis, optimum time of sieving