DECAY CONCRETE METERS
The corrosion problem
One of the most important and
worrying reasons of decay of the reinforced concrete structures is the corrosion
of the iron due to the loss of the characteristics of protection of the
The main reasons are:
- the phenomena of carbonatation, from
the external layers to the internal, reducing the alcalinity of the concrete
and destroying the passive film of the reinforce and triggering the corrosion
- the use of the antifreeze
salts which cause the penetration of the chloride ions until the reinforce
where the corrosive localized attack start.
- the atmospheric pollution
Although such phenomena are often
confined in small areas of the structures, their consequences are considerable
- the structural aspects and therefor
the safety conditions
- the functional aspects and the outward
state of the works
- the corrosive attacks by vacant
currents in the case of structures interested by electrical fields.
Kind of intervention
At the moment the main Companies engaged
in the maintenance of the motorway structures plan their activities and
fix the priorities o the interventions considering the results of
visual inspections and non-destructive tests elaborated in accordance with
Markovís process. This kind of approach is due to the big number of bridges
and viaducts to test.
clear that the process is in an advanced state in the moment where itís
visible the effects due to the corrosion of the reinforcements (delamination,
In the life of the reinforced concrete
structures itís possible to individuate two perfectly distinguishable phases:
- a phase of trigger of the corrosion
when the phenomena leading to the local or generalized destruction of the
protective film of the reinforcements start;
- a phase of propagation of the attack
starting from the moment when the protective film is destroyed.
To develop rational and economical
strategies to repair and to restore the structures itís necessary to acquire
reliable information about the level and the speed of advancement of
the corrosive decay.
Measurung before the risk of corrosion
and considering the residual life of the work, the decay can be avoid or
strongly reduced scheduling simple and cheap restoring interventions.
Aetech staff have designed and realized
the DECOMETERS to test the conservative state of the reinforced concrete works.
2M or DECOMETER 4M itís possible
- THE CORROSIVE STATE MONITORING OF
THE existing structures
- The systematic monitoring of the
corrosive state of the new constructions.
- The planning of the repair interventions
- A save in the maintenance of the
efficiency and safety
- The objective verify of the designed
choices and of the good realization of the works
- The maximum reduction of the consequences
of the interventions on the traffic