Plumb Line GL

Application

The inclination as well as the horizontal displacement of above and below ground structures, as well as of production plants, is of decisive importance for the evaluation of their behaviour and stability. A plumb installation can act as reference axis, from which the displacements observed at different levels can give the deflection line.

The normal plumb installation can be manufactured either as a plumb line or a float line, for which the wire is fixed at its upper or lower end respectively. Depending on whether this fixture is on the structure itself or in the foundation rock, either the inclination of the structure alone, or also its displacement relative to an external reference point can be determined.

A combination of the two types of installation gives the maximum information. For a dam for instance, a plumb line anchored on the crest yield the inclination and deflection line relative to the crest, whilst a float line, or inverted pendulum, fixed deep in the foundation rock gives the movement relative to the surrounding rock.

Description

A pendulum system consists of the plumb reference point FP (also called plumb suspension or plum pivot point), the plumb wire LTD, the plumb weight G and the damping vessel D. For manual measuring a Coordiscope KK84 (N or D) is used. The contactless remote measuring instrument Telelot VDD2V4 can be installed for permanent surveillance.

Legend:

A = Without moving the damping vessel

B = Coordiscope, Telelot all types

C = The maximum possible plumb wire length is mainly influenced by two factors:

       1. Measuring method with or without touching of the wire

       2. Air current in the plumb pit or generally in the building