For determination of the change in size of a concrete or cement sample, brought about by a change in moisture content, following apparatus has been designed. Tests can be performed on freshly made specimens or specimens taken from existing structures.

The apparatus can be used for three basic tests:

Initial drying shrinkage
The difference between the length of the cured specimen and the lenght when it is dried.

Drying shrinkage
The difference between the length of the specimen from existing structure and its length when completely dried.

Moisture movement
The difference between the length of the dried specimen and its length when again saturated with water.

The apparatus consists of a frame with adjustable cross head. The base is provided witha a stainless steel circular platen having a recessed seating and a 300 to 301mm long alloy steel reference bar having coefficient of the thermal expansion less than 2x10^-6mm/degC with 6mm dia steel balls mounted at the ends.