Encardio-rite model EDJ-40TJ triaxial crack/joint meter is used for surface measurement. Surface crack/joint measurements can be made either on the surface or at locations accessible from galleries (in case of dam).
EDJ-40TJ triaxial crack/joint meter for surface measurement consists of two precision machined elements attached to reinforce bar anchor stems. The precision elements are made of aluminum and are epoxy painted to make it corrosion proof. The micrometer rest blocks and mounting buttons are of stainless steel.
The measurement is made by anchoring the two elements on either side of the crack/joint and accurately measuring the distance between them over a period of time.The displacement is measured by a micrometer depth gage of 50 mm range and 0.01 mm resolution.