In a new construction of a seventeen-storey building, it is necessary to remove a prop on the second floor, which has made it possible to complete the structure of the building. In the drafting of the executive project, no security measures were described, because it was understood that they were not necessary. In the construction phase, the need to monitor the process was raised, and to be able to stop it, or reverse it if necessary. It is a reinforced concrete structure, with metal elements and composite elements, with a torsional behavior of the cores making the slabs serve as horizontal diaphragms, so the final behavior could be different from what was expected. To make this process possible, two pairs of four metallic cantilevers were introduced into which four Hydraulic pistons were inserted. Before starting the process, they were loaded to be sure that they would not fail. Strain gauges were also placed to control the stresses and how the situation changed during the unshoring process. The process of cutting the provisional pillar was a success, obtaining less deformations than expected, having a complementary safety.