C 136 and the American Association of State Highway and Transportation Officials (AASHTO) T 27 A suitable sieve size for the aggregate underneath the nest of sieves to collect the aggregate that passes through the smallest. The entire nest is then agitated, and the material whose diameter is smaller than the mesh opening pass through the sieves. After the aggregate reaches the pan, the amount of material retained in each sieve is then weighed. Preparation In order to perform the test, a sufficient sample of the aggregate must be obtained from the source. To prepare the sample, the aggregate should be mixed thoroughly and be reduced to a suitable size for testing. The total mass of the sample is also required. Results The results are presented in a graph of percent passing versus the sieve size. On the graph the sieve size scale is logarithmic. To find the percent of aggregate passing through each sieve, first find the percent retained in each sieve. To do so, the following equation is used, %Retained = ×100% where WSieve is the mass of aggregate in the sieve and WTotal is the total mass of the aggregate. The next step is to find the cumulative percent of aggregate retained in each sieve. To do so, add up the total amount of aggregate that is retained in each sieve and the amount in the previous sieves. The cumulative percent passing of the aggregate is found by subtracting the percent retained from 100%. %Cumulative Passing = 100% - %Cumulative Retained. The values are then plotted on a graph with cumulative percent passing on the y axis and logarithmic sieve size on the x axis. There are two versions of the %Passing equations. the .45 power formula is presented on .45 power gradation chart, whereas the more simple %Passing is presented on a semi-log gradation chart. version of the percent passing graph is shown on .45 power chart and by using the .45 passing formula. .45 power percent passing formula % Passing = Pi = x100% Where: SieveLargest - Largest diameter sieve used in (mm). Aggregatemax_size - Largest piece of aggregate in the sample in (mm). Percent passing formula %Passing = x100% Where: WBelow - The total mass of the aggregate within the sieves below the current sieve, not including the current sieve's aggregate. WTotal - The total mass of all of the aggregate in the sample.