(b) SHRINKAGE MOULD TEST: For this test you will need a mould called a linear shrinkage
mould. The mould can either be made from wood or metal. The plan shown below is for a
wooden mould.
Shrinkage is very important when choosing a soil for building. If a soil shrinks a lot it will
tend to cause cracks in a building. The more clay that is in a soil the more it tends to shrink.
When you have your mould box, or boxes, you will need to prepare the soil for the test. First
put the soil through sieve (5 or 6 mm should do). Now mix this soil with water until it is near
its "liquid limit". The way to test if the soil is at this limit is given below. You do not have to
have the exact equipment but the closer you keep to this method the more reliable your
results are.
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