What type of crack monitor for what type of crack?

To determine the ideal indicator for accurately measuring the evolution of a movement or a crack, it is essential to think about your needs. At Saugnac, we offer a diverse range of nearly twenty products, suitable for monitoring all movement situations.

Crack monitors for the most classic cases: the spreading of a crack

Crack monitoring on 1 axis

The “standard” case consists of following the evolution of the opening and closing of the crack. It involves monitoring a crack along a single axis.

An easy-to-read crack indicator

If you want the easiest-to-read, most accurate gauge for indoor or outdoor use, choose the G1+ crack monitor.
Its patented reading system means you don’t need to know how to read a vernier, avoids parallax-related reading errors (if you’re not exactly in front of the gauge) and can even read down to 0.05 mm.

The classic indicator if you know how to read a vernier

If you know how to read a vernier and need to track indoors or outdoors, choose the G1 crack monitor.
Simple, efficient operation. The included Saugnac application even lets you use a smartphone to read the vernier scale.

For indoor crack monitoring

If you only need to monitor cracks indoors, choose the G1.1 crack monitor. 
More economical, it is designed for installation in buildings and dry rooms only.

Transparent crack monitor

If you want to be more inconspicuous, choose the G1.2 crack monitor
Transparent, it works in the same way as the G1 and is resistant outdoors, but is less visible.

An economical digital fissurometer

If you’re looking for something more precise, more inconspicuous and more economical because you’ve got a lot of cracks to monitor: the E1 gauge with digital readout and 0.0 1mm resolution is the right solution.

Its transparent plates are fixed on either side of the crack with the screws supplied, and the gauge clips into the plates to take the measurement.

The advantage of this solution is that only the transparent plates remain on the support, and they are very small (3.3 cm diameter and less than 1 cm high).

What’s more, this solution limits damage, especially as the plates are made from a resistant material (PA12), the same one used for boat windscreen parts.
Since reading is digital, no special knowledge is required, and platinum refills cost less than G1 or G1+ gauges.

Crack indicators for more specific 1-axis tracking needs

Some cracks in walls have more specific needs, and require the use of an appropriate crack monitor.

A metal gauge

In certain cases, particularly in aggressive environments and/or if you want greater precision while leaving the gauge on the support, you can opt for the G1.5 crack monitor, which is an invar metal gauge with a resolution of 0.02mm and a very low coefficient of expansion.

The choice for wide cracks

If your crack is more than 15 cm wide, or if the anticipated amplitude of the crack is more than 2.5 cm, it will not be possible to use a G1 or E1 type gauge. You should therefore use a G1.3 crac monitor, which can measure cracks with large gaps and/or variations.

To record your measurements

If you need to know the measurements without being able to take them regularly, you can turn to the G2 crack monitor, which records the maximum and minimum measurements using a graphite lead. It’s a simple and effective way of finding out how far a crack is expanding or contracting, without needing a battery.

Which crack gauge should I use for a horizontal or oblique crack?

The orientation of the crack does not influence the choice of gauge. The principle is to position the gauge astride the crack. If the crack is horizontal or oblique, simply orient the gauge in the right direction, perpendicular to the crack.

Which crack indicator to use to monitor an angled crack?

The G1 family of gauges (except G1.5) are all supplied with a bendable clip for fixing at an angle. All you have to do is bend the bar at the stress point to the required angle and then fix the gauge with the bent bar. Examples of angled fixings can be found in the product data sheets.

For environments subject to high stress, it is also possible to purchase an aluminium angle for use in place of the folding plastic strip.

Crack monitoring for spread and shear walls

The aim is to take into account movement along two axes. For example, in the event of differential ground settlement, the crack may not only open up, but also move laterally, as the movement occurs along two axes. So you need to choose a solution that can monitor both axes.

More generally, if you are unsure of the type of movement, it may be more prudent to opt for a solution that allows measurement along both axes. This ensures that all the data required for full analysis and interpretation is collected.

We offer 2 solutions for 2-axis tracking:

  • A mechanical solution with the G6 gauge, which has 2 verniers and can track movement on 2 axes. Measurements can be tracked directly in the application.
  • An electronic solution with the E1 gauge, which also offers 2-axis tracking by positioning 3 plates. The X and Y projection is then calculated in the application. You can find more information on the E1 gauge product sheet.

Crack indicators for misalignment cases  

When faced with problems such as sagging ceilings or floors, broken paving or misalignment of pillars or walls, the G3 crack monitor offers a versatile solution.

Its unique cubic design makes it possible to follow the evolution of a displacement, whether horizontal or vertical, offering exceptional flexibility. With a measurement resolution of 0.1 mm, the G3 ensures remarkable accuracy, and its use is simplified by the free Saugnac.app app.

Mounting can be carried out using the adhesives supplied, and a mechanical mounting with intermediate plate is available as an option.

For detailed graphical tracking of progress, an optional recording kit is also available, guaranteeing complete and precise monitoring of disaffection over time.

Crack indicators for wall or balcony inclination

We offer inclinometers from the G5 range. These gauges, based on the simple and effective pendulum principle, are designed to monitor the inclination of a structure. All these gauges can be fixed flat or perpendicular using brackets.

Whatever the tilt tracking problem: the G5 gauge, which tracks the variation of an angle of 0.03°.

The economical version

If gauge size and/or price are priorities over measurement resolution: the G5mini gauge is an alternative. It is half the size of the G5 gauge, cheaper but with half the resolution (0.06° resolution).

The removable solution

If you have a lot of points to monitor and/or you don’t want to leave the gauge in place, the G5+ gauge with a mounting plate is recommended. This gauge is removable and attaches to a plate for measurement. It has two advantages:

  • It does not remain permanently on the support: once the measurement has been taken, it can be stored in its case, avoiding any risk of damage or deterioration.
  • The purchase of plates is more economical than the purchase of gauges (and protective covers, where applicable).

For 3-dimensional motion monitoring

If you need to monitor the displacement of one structure relative to another in three dimensions using a single tool, the 3DIM gauge is the universal tool that enables you to track the millimetre-scale evolution of structures in three dimensions simply and accurately.

Equipped with three verniers and a calculation file, this solution can track any type of movement. It is installed by fixing two metal plates that serve as reference points for the measurement. The gauge is removable and is only positioned on the plates to take the measurement. This system, for example, is much simpler to install than a vinchon.

In simple configurations requiring three-dimensional tracking, it is also possible to use a combination of two-axis measuring instruments and a defocuser, using, for example, a G6 + G3 gauge or an E1 + G3 gauge.

Measurement tools for beam/ceiling bending 

The G130 gauge from Saugnac Jauges stands out for its ability to measure the evolution of a deflection, the tilting of a wall or the deformation of a structure in compression with a fine resolution of 0.1 mm, or 0.2 mm of movement.

This tailor-made device offers a solution adapted to specific problems, requiring an in-depth study of each case in order to propose a customized solution.

Each G130 solution is supplied with instructions and an installation plan tailored to the specific constraints of each project. This personalized approach guarantees optimum integration of the crack detection system into the user’s specific environment.

Monitoring the distance between 2 points several metres apart

The Saugnac recording tensiometer, also known as the G20 gauge, enables precise monitoring, to within 1/10th of a mm, of changes in the distance between two points several meters apart and several meters high.

In fact, this station offers precise verification of the constancy of the distance between two parallel walls. This is typically the case for the vacuum thrust of church walls. Thanks to its remote unit, the measurement can be read at ground level. In addition, the solution is based on the G2 gauge, with graphic recording of minimum and maximum values.

This proven technology guarantees reliable, precise monitoring of variations over time, making it an ideal solution for projects where consistency of distance between two points is crucial.

If you have any doubts or specific requirements, please contact us to discuss them.