砂のふるい分析に関する誤差

In this study, the splitting, classifying and sieving errors in sieve analysis of sand were investigated. The conclusion is as follows :
1. Even an unexperienced person can obtain the sieving data of practically allowable accuracy by means of careful analysis.
2. Considering the splitting and sieving errors, it is proper to tabulate the sieving data in this study down to one place of decimals.
3. In sieve analysis that tests the unique grading, a choice of sieve openings corresponding to the geometrical series of suitable geometrical ratio should be conformed to the actual condition of the grading of the sand in question.
4. Two sets of sieves, those standardized in JIS A 1204 and JIS A 1204 (E), are not suitable, in case of obtaining the unique grading.