Digital Movement Gauge developed by the BCA DEMEC

Digital Movement Gauge

Developed by the BCA to measure movements at joints or cracks in a structure

Introduction

The Digital Movement Gauge was originally developed at the BCA for measuring the movement at joints or cracks in a structure.
While not as accurate as a Demec gauge, its direct reading digital output makes it much simpler to use. For joint or crack movements, the accuracy is perfectly acceptable.

Description

The instrument consists of a steel beam with a fixed locating point at one end. An accurately guided slide is mounted on the steel beam and is able to traverse its full length. A second locating point is fitted beneath the slide. The slide carries a digital read-out head which registers its movement relative to an electronic scale built into the top surface of the beam. The change in digital reading thus giving the relative movement between the two locating points.

The digital readout is fitted with a number of small switches, which allow the following functions to be performed:

ON/ZERO : this switches on the read- out, and then allows the reading to be set to zero at any desired position

OFF switches off the read-out

in/mm sets the measurement units to those shown on the right of the digital display.

Operation

Demec studs are attached to the structure at points either side of the crack or movement joint under investigation. The movement gauge is then inserted into the studs and the reading noted. At any time required, the movement gauge can be re-zeroed on the reference bar and additional readings taken.