1 The first thing to be considered when testing aggregate quality is the Size Number. This number regulates which set of sieves will be used to sieve the aggregate. ASTM C-33 Grading Table provides aggregate size numbers and corresponding sieves for each number. Each size number is listed in the first column on the next slide. The sieves to be used to test a particular grade are read across the row. Let’s consider the ASTM C-33 Gradation Table If the sieve shows a …. then it is not to be used for sizing that particular aggregate size.

2 Grading Requirements for Coarse Aggregates Amounts Finer than each Laboratory Sieve (Square Openings) Cumulative Weight Percent 0 to 50 to to to …. 1/2” to # to 4.75 mm 7 …. 0 to 50 to to to …..... …. 1” to 1/2” 25 to 12.5 mm 5 …. 0 to 5….0 to to to …..... …. 1½” to 3/4” 37.5 to 19 mm 4 0 to 5 0 to to to …. 3/8” to #8 9.5 to 2.36 mm 8 0 to 50 to to 55 ….90 to …. 3/4” to #4 19 to 4.75 mm 67 ….0 to 50 to to to …. 3/4” to 3/8” 19.0 to 9.5 mm 6 0 to 50 to 10 ….25 to 60 ….95 to …..... …. 1” to #4 25 to 4.75 mm 57 ….0 to 50 to to to to …..... …. 1” to 3/8” 25 to 9.5 mm 56 ….0 to 510 to 30 ….35 to 70 ….95 to …..... …. 1 ½” to # to 4.75 mm 467 ….0 to 5….10 to 30 ….35 to 70 ….95 to …. 2” to #4 50 to 4.75 mm 357 …. 0 to 5….0 to to to …. 2” to 1” 50 to 25 mm 3 …. 0 to 5….0 to 1535 to to …. 2 ½” to 1 ½” 63 to 37.5 mm 2 …. 0 to 5….0 to 15….25 to 60 ….90 to ½” to 1½” 90 to 37.5 mm 1 No mm No mm 3/8” 9.5 mm 1/2” 12.5 mm 3/4” 19 mm 1” 25 mm 1½” 37.5 mm 2” 50 mm 2½” 63 mm 3” 75 mm 3½” 90 mm 4” 100 mm Nominal Sieves w/sq openings Size #

3  Plotted as Cumulative % finer by weight versus sieve size  Begins in upper left at 100%, ends in lower right close to 0%  Large drop means most material of that particle size  Vertical drop means uniform particle size  Graded drop means mixture of various particles –called non uniform.  Clean material (with few fines) end in lower right of graph near X axis (close to 0%) In the following pages we will examine each aggregate size listing that is useful for septic drainfields. By examining the table and the graph we will be able to determine the predominate size, uniformity, and percent of fine particles in an aggregate sample.  Size # 1-8  The higher the number, the smaller the aggregate size (this is the opposite of shoe sizes)  Table gives % variation on each sieve used  Most material is found on the sieve with widest range in % s  Single digit size numbers are uniform (for example #4)  2nd & 3rd digit (as in #357) widens the range of acceptable particle sizes Aggregate SIZE NUMBERS Information Overview

4 The previous chart includes all coarse aggregate. On the following slides we will take a closer look at the specific aggregate sizes that affect Septic contractors. DOT Sizes; 357,4, 467 & 5 always fall in the Gradation Range appropriate for septic drainfields in Florida. DOT Sizes 3, 56, & 57 sometimes fall in this range, but not always. In addition, the state standard allows no more than 3.75% by weight to pass the No. 200 sieve (dust-sized particles) 0-5%No %3/8” 0-50%1/2” 0-70%3/4” %1” %1½” %2” Cum. % Passing Sieve Size

5 Gradation Requirement Cumulative % finer by weight minimum) Cumulative % finer by weight (maximum) The shaded area in between the minimum & maximum cumulative % finer by weight, represents the acceptable range for aggregate in drainfields. This is a wider range than any of the DOT sizes. In addition, the state standard allows no more than 3.75% by weight finer than the No. 200 sieve (dust-sized particles) 0-5%No %3/8” 0-50%1/2” 0-70%3/4” %1” %1½” %2” Cum. % PassingSieve Size

6 Any points found to the LEFT of the green line; the aggregate would be too large. Likewise any point found to the right of the red line; the aggregate would be too small for drainfields. Gradation Requirement Larger smaller 0-5%No %3/8” 0-50%1/2” 0-70%3/4” %1” %1½” %2” Cum. % PassingSieve Size

7 Let’s take a closer look at one specific DOT size. DOT # 3 DOT Size # 4” 100mm 3 ½” 90 mm 3” 75mm 2 ½” 63mm 2” 50mm 1 ½” 37.5mm 1” 25mm 3/4” 19mm 1/2” 12.5mm 3/8” 9.5mm No mm No mm Nominal Size Sieves w/sq openings 2” to 1” 50 to 25 mm …. 100…. Reading across the row you can see that the 2½”, 2”,1 ½”, 1”, and the 1/2” sieves would be used and stacked in order as shown below. Stacked with the largest square openings on the top to progressively smaller openings and a pan to catch fine material. 90 to10035 to 700 to 15….0 to 5 3

8 DOT Size # 4” 100mm 3 ½” 90 mm 3” 75mm 2 ½” 63mm 2” 50mm 1 ½” 37.5mm 1” 25mm 3/4” 19mm 1/2” 12.5mm 3/8” 9.5mm No mm No mm Nominal Size Sieves w/sq openings 2” to 1” 50 to 25 mm … to10035 to 700 to 150 to 5 …. Graphed DOT # 3 would look like this. …. Y Axis = Cumulative % of material that falls through the sieve. 0__ 20__ 40__ 60__ 80__ 100__ X Axis= Sieve square opening size. 2½”2”1½”1” ½” At 2” 90 to 100% will fall through. 0% to 10% may remain on the sieve. Represents cumulative % finer by weight (maximum) Represents cumulative % finer by weight (minimum) Notice at the 2½” sieve 100% of the material will fall through the sieve. 0% will remain on the sieve. X Y 3

9 DOT Size # 4” 100mm 3 ½” 90 mm 3” 75mm 2 ½” 63mm 2” 50mm 1 ½” 37.5mm 1” 25mm 3/4” 19mm 1/2” 12.5mm 3/8” 9.5mm No mm No mm Nominal Size Sieves w/sq openings 2” to 1” 50 to 25 mm … to10035 to 700 to 150 to 5 …. Graphed DOT # 3 would look like this. …. 0__ 20__ 40__ 60__ 80__ 100__ 2½”2”1½”1” ½” Represents cumulative % finer by weight (maximum) Represents cumulative % finer by weight (minimum) At 1½” the minimum cumulative finer by weight is 35% & 70% is the maximum that can fall through. Conversely as much as 65% may remain on this sieve and the two above it, or as little as 30% may remain on this sieve or the ones above it. 3

10 DOT Size # 4” 100mm 3 ½” 90 mm 3” 75mm 2 ½” 63mm 2” 50mm 1 ½” 37.5mm 1” 25mm 3/4” 19mm 1/2” 12.5mm 3/8” 9.5mm No mm No mm Nominal Size Sieves w/sq openings 2” to 1” 50 to 25 mm … to10035 to 700 to 150 to 5 …. Graphed DOT # 3 would look like this. …. 0__ 20__ 40__ 60__ 80__ 100__ 2½”2”1½”1” ½” Represents cumulative % finer by weight (maximum) Represents cumulative % finer by weight (minimum) At 1” the maximum finer by weight is 15%. This means 85% will be on this sieve or the sieves above it. The minimum finer by weight is 0% therefore all of the material could be on this sieve & the sieves above it. At 1/2” the maximum finer by weight is 5% and the minimum is 0%. So as much as 100% or as little as 95% could be on or above this sieve 3

11 DOT Size # 4” 100mm 3 ½” 90 mm 3” 75mm 2 ½” 63mm 2” 50mm 1 ½” 37.5mm 1” 25mm 3/4” 19mm 1/2” 12.5mm 3/8” 9.5mm No mm No mm Nominal Size Sieves w/sq openings 2” to 1” 50 to 25 mm … to10035 to 700 to 150 to 5 …. Graphed DOT # 3 would look like this. …. 0__ 20__ 40__ 60__ 80__ 100__ 2½”2”1½”1” ½” Represents cumulative % finer by weight (maximum) Represents cumulative % finer by weight (minimum) The green & red lines represent the minimum & the maximum cumulative finer by weight percents. All of the area in between the lines is in an acceptable range. If any data points fall to either side of the polygon then the test sample is not DOT #3. Now that we have all of the maximum & minimum cumulative finer by weights plotted, the points may be connected. 3

12 DOT Size # 4” 100mm 3 ½” 90 mm 3” 75mm 2 ½” 63mm 2” 50mm 1 ½” 37.5mm 1” 25mm 3/4” 19mm 1/2” 12.5mm 3/8” 9.5mm No mm No mm Nominal Size Sieves w/sq openings 2” to 1” 50 to 25 mm … to10035 to 700 to 150 to 5 …. Graphed DOT # 3 would look like this. …. 0__ 20__ 40__ 60__ 80__ 100__ 2½”2”1½”1” ½” Represents cumulative % finer by weight (maximum) Represents cumulative % finer by weight (minimum) You will notice on the graph that the 1 ½” sieve is where there is the steepest drop. And in the table it has the broadest range (35 to 70). This is the size range of most of the aggregate material. Therefore 1½” is the Predominate Size of this sample. The prefix “uni” means one. If a large portion of the aggregate remains on one screen then the sample is uniform size. 3

13 DOT #3 Gradation Standard (blue line) Inspect this graph carefully. The blue line represents the gradation requirements for the State of Florida drainfield aggregate. The red & green lines represent cumulative percent by weight maximum & minimums we just plotted. Notice that part of the green line extends to the left of the state requirements. This means that sometimes #3 aggregate will be too large for state standards. A small size #3 would fit state standards.

14 DOT Size # 4” 100mm 3 ½” 90 mm 3” 75mm 2 ½” 63mm 2” 50mm 1 ½” 37.5mm 1” 25mm 3/4” 19mm 1/2” 12.5mm 3/8” 9.5mm No mm No mm Nominal Size Sieves w/sq openings 2” to 1” 50 to 25 mm … to10035 to 700 to 150 to 5 …. Graphed DOT # 3 would look like this. …. 0__ 20__ 40__ 60__ 80__ 100__ 2½”2”1½”1” ½” Represents cumulative % finer by weight (maximum) Represents cumulative % finer by weight (minimum) The amount of fine particles can be determined by looking at the graph. The closer the polygon is to the x axis the less fine material is included in the sample. 3