These are two buildings, the cement mill and the pre-homogenization tower at the Lafarge group “Aget-Heracles” plant, in Volos, which had to be strengthened against earthquakes.

The cement mill building is approximately 50 meters high and the pre-homogenization tower 66 meters.

They were made of reinforced concrete in the 1970s and are separated with an “expansion-joint”.

The goal was to limit deformation and therefore damage in a subsequent earthquake.

To reduce deformations, an increase in stiffness is required, and at the same time an increase in the damping of the oscillation energy.

The proposed method suggests the installation of steel “Λ”-shaped trusses on all levels.

At the top of the steel “Λ”-shaped trusses there is a steel connection, which can deform plastically during the earthquake, without failing and thus absorbing energy by reducing the differential displacements.

The method is simple, can be applied without interrupting the plant’s operation and is very economical.

The passage of many electrical and mechanical installations through the “wall-infill” of the frames, created some obstacles to the installation of the steel “Λ-shaped” trusses.