All compaction specification include a criteria to obtain minimum dry unit weight, γd. Using the Standard Proctor Test (ASTM Standard D698) method γd, max and ωopt were obtained graphically. To achieve the reading of the γd, max and ωopt graphically, the procedures of (ASTM Standard D698), were followed. A 2.49 kg hammer was dropped from a height of 305 mm at a rate of 25 drops per layer and with accordance with (ASTM Standard D698), there were a total of 3 layers, Figure c1.

 

 

 

 

 

 

 

 

 

 

 

 

See ASTM Standard D698 for further information on the procedures.

 

 

 

 

 

 

 

 

 

To obtain the required data points to plot on a graph (figure c2) equation c1 was used

 

 

Thus, equation c1 was re-written to computing data point no. 1, from table 1

 

 

 

Using equation 3 (see specific gravity lab),

 

Mass of Tin can: 13.95g

Mass of Tin can + Sample: 100.35g

Mass of Tin can + Dry sample: 96.19g

 

 

 

 

Using equation c1 and equation 3, the dry unit weight was computed by using equation c2 

 

 

 

Thus, these plots point correspond to ω = 5.06%, γd = 15.57 kN/m^3. The same process was followed for all point in table 1 and result are in table c2.

 

 

 

 

 

​It was necessary, based on empirical data to compute the peak of compaction curve that occurs roughly at a degree of saturation, S, of about 80%, as shown in figure c2. Also necessary is zero air void curve S=100%. To compute both saturation curve equation c3 was used, and table c3 was obtained.

 

 

 

 

 

 

 

 

 

 

To plot the data points ,Dry unit weight was plotted vs moisture content. This allowed to determine the max dry unit weight and optimum water content, which was where the data intersected the 80% saturation curve. The ZAV line gave the upper limit of the data. Furthermore, another component that was determined from the plot, is the Field Specification of 97% γd, max.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

​​ The final results are: 

 

 

 

 

 

 

The compaction curved obtained from the soil in figure c3 gave a good indication that the test was done right as there is a defined slope. Using table c4, for a typical sand the dry weight ranges from 14.7 kN/m3 to 22.6 kN/m3, comparing the final results, the soil points to a dry unit weight of sand.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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