Car Park Under Repair: Making the Success Measurable

Challenge

The damage first, then the costing

As a result of high mechanical loading and chloride exposure, damage became visible on the levels of the underground car park: cracks and spalling. To get an accurate picture, the car park was inspected and the damage was catalogued.

That described the problem, but did not solve it. The client commissioned a trial repair, with two goals: verify the repair costing and determine a technology that fits this building and this damage. A trial repair is only as good as the measurement that proves its result.

Solution

Sensors in the crack area, plus a reference point

Repair principle “W” and the extraction of salts from the columns were used. For verification, moisture and corrosion monitoring systems were deployed, standard moisture and corrosion sensors, installed in the crack area of the construction joint and bonded to the existing concrete via coupling mortar.

One part of the setup is easy to overlook and makes the difference: moisture sensors sit not only in the repair area but additionally in an unloaded area of a bay. This reference point delivers the comparison value. Without it, every change in the repaired area would just be a number; with it, it becomes a statement.

Readout

A reader matched to the installation depth

Readout was done manually with a handheld reader. The device must match the installation depth of the sensor, versions exist for 10 cm and for 30 cm. A remote query of the sensors is also possible, and through it the inspection intervals can be steered instead of set by calendar.

Result

Proof that the repair holds

The benefit lies in the chain after the measurement. The structure’s condition is easily visible, the success of the repair can be proven, and if the surface protection system fails, repairs can target specifically where they are needed. Because the moisture readings can be queried, inspection intervals are steered deliberately, and early detection of damage significantly lowers the cost of later concrete repairs. For operation, this ultimately means shorter closures for future measures.

The project shows how concrete monitoring and moisture and corrosion monitoring accompany a repair in parking structures. If you are planning a repair and want to be able to prove its success, describe your structure to us through our project inquiry.