How to control the moisture in the soil to do lab testing/offsite testing for thermal resistivity of soils?

Question

The moisture of the soil is very hard to maintain. It affects the results of the test causing a huge inaccuracy in the results. In order to prevent any modification/cheating of the results, I need to have a very good way to contain the moisture in the soil in the TR mould.

Answer 1

The other answer had some good ideas- if you can control the humidity in the room, the soil should not dry out- However, this will also allow condensation or dew to form in the room and could damage expensive lab equipment.

Something else you might try is to weigh a sample at optimum testing and then immediately wiegh it. Then heat it and boil off all the water and weigh it again. The difference in wieght can be attributed to water. The ASTM and others have procedures for determining how to scientifically accomplish this.

Now, with that information, you can just keep your soil dry- and then add the appropriate amount of water just before you test it.

Answer 2

Moisture in soil depends on the temperature and humidity of the surrounding. If your test material is kept in a desiccator, it is controlled. Try to use Activated silica in order to absorb moisture. If you want the moisture to be maintained, condition the atmosphere around it, or condition the humidity around it. You can use a humidity meter to measure the humidity to the required level.