We recommend the following methods of measuring pile displacement. Tips as below:

Telltale wire
Transfer the displacement with steel wire (so-called telltale wire). Tie the lower end of the telltale wire at the needed position of the steel reinforcement cage a nd let the upper end extend out of the ground surface.

Conduit
The conduit with hard shell protects the telltale wire from the concrete.

Fixed pulley
Install a fixed pulley on the datum beam on the ground. Each telltale wire needs an independent fixed pulley.

Balancing weights
The telltale coils the fixed pulley and joints a 6~8kg weight balancing block.

Measurement base
Install a measurement base at suitable position on the telltale wire. The displacement of the base synchronizes with the one at the measuring point of the pile.