Is there a danger of collapse? The signal to anticipate corrosion

A football stadium can accommodate tens of thousands of people. On the A2 motorway (Zaragoza-Mediterranean) almost 8,000 vehicles pass every day on average per kilometer, according to data from the Ministry of Public Works. These are two examples of types of construction in which security is especially taken into account to transmit confidence to its users and occupants.

Safety in equipment is a very broad concept and among the factors that are reviewed is corrosion. It is the number one enemy of constructions built from reinforced concrete, such as bridges, viaducts, stadiums, ports or water tanks.

Corrosion depends on extreme temperatures; relative humidity (how much water vapor is in the air compared to how much it could hold at that temperature); aerosolized particles in the atmosphere, such as dust and sea spray, or air pollution from human and industrial activity. Corrosion also depends on the process and the quality of construction.

For example, in a saline environment such as the proximity to the sea of ​​a port, the water, when vaporized, penetrates to the metal structure of this and oxidizes it. Just imagine how a bicycle looks if we leave it moored near a beach for a while. The saline agents from the water vapor enter through the cracks or microcracks in the concrete of the port walls and accelerate their corrosion process.

In another scenario, a highway, cracks can arise from the circulation of vehicles, especially if they are very heavy trucks. Cracks in the concrete can also be generated during the construction process.

A Catalan company has devised a system to detect the level of corrosion in buildings and act before it is too late, as was not done on the Morandi bridge in Genoa (Italy) in 2018 when, after an episode of storms and heavy rains , 210 meters of its structure and one of the support towers fell, resulting in the death of 43 people.

Precisely, at two points on the A2, 62 and 139,500, considered highly critical due to the volume of traffic and the severity of the injuries suffered, this solution was applied taking advantage of the recovery work in the area. “The A2 is one of the roads most threatened by the effects of the weather, due to the high risk of frost between November and April, which requires applying large amounts of salt to keep the road passable. This had caused serious corrosion problems on the track”, explains Ignasi Cairó, CTO of Witeklab.

How was this deterioration managed to be stopped? “What this technology achieves is anticipating corrosion. We install internal sensors at different points of the structure that react to the oxidation process because they detect the internal galvanic currents that produce it and provide real-time information on the oxidation situation, they tell you if the problem is minor or serious”, says Cairó. From here, a construction maintenance plan is drawn up.

All this information is measured and sent to the cloud, where an algorithm establishes the exact degree of oxidation and its speed. The client can monitor this process and receive alarms and reports. Therefore, behind this solution are technologies such as artificial intelligence, the cloud, the Internet of Things or advanced sensors, to detect currents, however small they may be.

Among the constructions where this disruptive technology has already been applied are, in addition, the port of Mahón (Menorca), that of Gijón (Asturias), several brine discharge towers from Llobregat or a water tank in Sallent (both in Barcelona). . This construction protection system is applicable not only to existing infrastructures, but also to the construction process of new ones.

In addition to corrosion, this company has devised a method to monitor the resistance of concrete when a structure is being built or rehabilitated. It consists of introducing sensors into the concrete that will return information on this resistance throughout the process, when until now, this data could only be known at a certain moment: “controlling the resistance curve is essential to continue advancing in a construction, for example , of a bridge, knowing if that concrete is strong enough”, says Cairó.

“Also, through some antennas, we have managed to detect when there is an underground pipe to avoid drilling it when the ground is being worked, for example, in street repairs, and finally, we use the sensorization of the anti-slide barriers that are placed in roads to anticipate these incidents. If the sensors detect a movement of stones or an extra weight on the barrier, an alarm goes off so that we can act in time”, concludes Cairó.

All this technology also “gives much more security, avoids efforts and accidents by personnel and reduces unnecessary travel, minimizing CO2 emissions into the atmosphere. This is added to the saving of money in the future maintenance of the infrastructures”, points out Manel Torrentallé i Cairó, CEO of Witeklab.

Currently, this startup born six years ago works to provide its algorithms with greater intelligence to gain even more anticipation for any event.

This and other investigations have already been carried out since January of this year in the new industry 4.0 ecosystem of the Consorci de la Zona Franca de Barcelona, ​​DFactory Barcelona. “The experience since we have been here has been very pleasant. We have been able to meet companies in the sector and make contacts inside and outside Spanish territory, in addition to establishing synergies with some companies”, says Manel Torrentallé.

Among the companies that inhabit this new ecosystem, in addition to sensors, there are those from sectors such as robotics, the automotive industry, 3D printing, blockchain, advanced manufacturing or photonics. And the DFactory project does not end here, but continues to grow with the incorporation of new companies to the current plant (17,000 square meters) and with the construction of a second plant (70,000 square meters).

For Pere Navarro, special delegate of the State in the Consorci de la Zona Franca de Barcelona, ​​the first DFactory plant “is exerting a positive effect calling on companies that are working in industry 4.0, since coming to a place where there are already other Companies that are working on these technologies can only bring them benefits.”

“With these synergies, we want to change the Spanish industrial fabric, support companies during their digitization process and turn Barcelona into the center of 4.0 innovation in southern Europe”, he concludes.