Description of the procedure for finding the plastic and liquid limits of a soil using ASTM D-4318. Filmed at Tufts University for CEE 42 - Intro to Geotechnical Engineering.
+Steven Woodruff 1) The soil sample that you roll into an ellipse for the plastic limit test should be approximately 2 grams. 2) The plastic limit is defined as the moisture content at which an ellipsoidal mass of soil 1/8 in. in diameter just crumbles when rolled. The ellipse in this video is probably 1/2 in to 1 in in diameter. 3)The groove should be cut from the top of the cup down for the liquid limit test. 4)Get your hand off the liquid limit device when turning the crank. 5)The closure of the soil pat should only be 1.3 cm. The length of the soil pat closure is approximately 1.5 in. in the video. 6) The crank should be turned at a rate of two blows per second. The person is this video is turning the crank too quickly.
You should rename this: How not to run Atterberg Limit Tests.
Why?
+Steven Woodruff
1) The soil sample that you roll into an ellipse for the plastic limit test should be approximately 2 grams.
2) The plastic limit is defined as the moisture content at which an ellipsoidal mass of soil 1/8 in. in diameter just crumbles when rolled. The ellipse in this video is probably 1/2 in to 1 in in diameter.
3)The groove should be cut from the top of the cup down for the liquid limit test.
4)Get your hand off the liquid limit device when turning the crank.
5)The closure of the soil pat should only be 1.3 cm. The length of the soil pat closure is approximately 1.5 in. in the video.
6) The crank should be turned at a rate of two blows per second. The person is this video is turning the crank too quickly.
Good to know!