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Techniques Used for Testing the Moisture Content in Soil

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Imperatively, soil testing is one of the most important steps when you want to start any building project. It helps you determine the varying chemical and physical attributes of the soil as they differ from one place to the other within the site. Of importance too is the moisture content of the soil, which has a direct impact on the soil's ability to stand up to the load imposed on it by the building. So what are some of the techniques that modern soil experts use to test moisture content in the soil? Here is a look at what you will find in the market:

The Oven Drying Method

The oven drying method is one of the popular methods used by soil experts to test the moisture content in soil. First, the expert surveys the construction site and takes a sample that will represent the whole mass of soil on your site. Once the wet sample has been taken up, the expert puts it in a clean, dry container whose weight has been measured and recorded. The wet soil is then heated in an oven until its weight becomes constant. Normally, this takes one day for the most accurate results to be achieved. The difference in the weight of the wet and dried soil samples indicate how much water the soil has. 

The Sand Bath Method

The sand bath method comes in handy when you are in a remote construction site and there is no electricity to power an electric oven. The expert places sand on a tray to a height of around three centimetres, and the container holding the wet soil is dried by putting it on the sand bath, heating and stirring. A few pieces of white paper are placed over the container holding the wet soil, and the soil will only be deemed dry when the white papers develop a brown colouration. The dry soil is then taken and its moisture content determined by an analytical mathematical equation based on the masses of the wet and dry soils.

Alcohol Method

Here, a weighed wet sample is put in an evaporating dish. The expert adds methylated spirit, a millimetre for every one gram of soil, before stirring thoroughly with a knife to make sure that it has mixed properly. The mixture is then heated and the mass of the dry soil measured after all the methylated spirit burns away. This procedure takes nearly ten minutes.

The sand bath and alcohol method are field methods while the oven drying method is laboratory oriented.