Plaster Cast Method for Determining Soil Bulk Density.

Bulk density is an important soil property but its measurement is difficult in some soils due to gravel content or loose sandy material.  We developed a method that allows bulk density measurement in some of these problematic soils.  About 200 cm3 of soil material is excavated from a horizon and saved for drying and weighing.  The volume of the excavation is obtained by making a plaster cast of the excavation.  Dental plaster dries in 6-10 minutes and can be transported with little danger of breakage.  The volume of the cast is measured in the lab by volume displacement or 3-D scanning