Determining the Liquid Limit of Soil - Soil Properties: Testing, Measurement, and Evaluation - page 84

Determination No. 1 2 3

Number of drops 30 23 18

Can no. A-1 A-2 A-3

Mass of can + moist soil, M cws 34.06 g 32.47 g 37.46 g

Mass of can + dry soil, M cs 27.15 g 25.80 g 29.00 g

Mass of can, M c 11.80 g 11.61 g 11.69 g

The moisture content for each determination can be computed using
Eq. (4-1). For the first determination,

M w M cws M cs

M w 34.06 27.15 6.91 g

M s M cs M c

M s 27.15 11.80 15.35 g

M w

w

M s 100

(4-1)

6.91
15.35

w 100 45.0 %

Moisture contents for the second and third trials can be computed sim-
ilarly. All results are shown on the form on page 86. (At the end of the
chapter, two blank copies of this form are included for the reader's use.)
After the moisture contents have been determined, the flow curve
can be obtained by plotting, on semilogarithmic graph paper, moisture
content along the ordinate (arithmetical scale) versus number of drops
along the abscissa (logarithmic scale) and drawing the best-fitting
straight line through the plotted points. This is shown in Figure 7-6.

Figure 7-6
Flow Curve

50

49

48

47

Liquid limit = 46.4%

46

45

44

10 15 20 25 30 35 40 50 60

Number of drops