Tests on soil
Density of soil ( Sand replacement method)
Code: This test is done as per IS: 2720 (Part XXVIII) – 1974.
Procedure:
The method described below should be followed for the determination of the bulk density of the sand ( Ys ):
- i) The internal volume (V) in ml of the calibrating container should be determined from the weight of water contained in the container when filled to the brim. The volume may also be calculated from the measured internal dimensions of the container.
- ii) The pouring cylinder should be placed concentrically on the top of the calibrating container after being filled to the constant weight (W1). The shutter of the pouring cylinder should be closed during the operation. The shutter should be opened and sand allowed to runout. When no further movement of sand takes place in the cylinder, the shutter should be closed. The pouring cylinder should be removed and weighed to the nearest gram.
- iii) These measurements should be repeated at least thrice and the mean weight (W3) taken.
Measurement of soil density
The following method should be followed for the measurement of soil density:
- i) A flat area, approximately 450sq.mm of the soil to be tested should be exposed and trimmed down to a level surface, preferably with the aid of the scraper tool.
- ii) The metal tray with a central hole should be laid on the prepared surface of the soil with the hole over the portion of the soil to be tested. The hole in the soil should then be excavated using the hole in the tray as a pattern, to the depth of the layer to be tested upto a maximum of 150mm. The excavated soil should be carefully collected, leaving no loose material in the hole and weighed to the nearest gram(Ww). The metal tray should be removed before the pouring cylinder is placed in position over the excavated hole.
- iii) The water content (w) of the excavated soil should be determined as discussed in earlier posts. Alternatively, the whole of the excavated soil should be dried and weighed (Wd).
- iv) iv. The pouring cylinder, filled to the constant weight (W1) should be so placed that the base of the cylinder covers the hole concentrically. The shutter should then be opened and sand allowed to runout into the hole.The pouring cylinder and the surrounding area should not be vibrated during this period. When no further movement of sand takes place, the shutter should be closed. The cylinder should be removed and weighed to the nearest gram (W4).
To determine the dry density of soil by sand replacement method.