Seismic improvement and adaptation
Italy, with its rich architectural and cultural heritage, is a country vulnerable to earthquakes, making seismic adaptation and improvement of buildings essential. The growing awareness of seismic risks has made interventions on historic and modern buildings a priority to ensure the safety of people and the protection of the works that contribute to the beauty of our country.
The decision to carry out seismic improvement or seismic retrofitting often depends on economic, technical and historical considerations. Seismic retrofitting , which involves achieving the safety levels required for new buildings, is often expensive: it requires significant investments and in-depth interventions on structures characterized by seismic vulnerability. However, the investment in retrofitting translates into a drastic reduction of the risk to people's lives and to the preservation of assets.
Seismic retrofitting , on the other hand, is an intermediate solution that increases safety without necessarily reaching the maximum levels required by the regulations. This option may be more feasible and less invasive, especially in the case of historic or protected buildings.
Intervention techniques: strengthening real estate assets
Once the seismic vulnerability of a building has been identified, it is essential to undertake a consolidation process . There are several innovative and traditional techniques that can be used for anti-seismic strengthening:
● Structural reinforcement : involves the insertion of materials such as composite materials to improve the resistance of the load-bearing elements. For example, in stone walls, reinforced mortar injection techniques can be used to reinforce the walls.
● Installation of seismic isolators : these are devices that separate the load-bearing structure from the ground, reducing the oscillations transmitted to the structure during a seismic event. Seismic isolators are particularly effective in new buildings, but can also be implemented in existing buildings with particular precautions.
● Seismic damping systems : These are technologies that dissipate seismic energy during an earthquake, reducing the displacement of the structure. Seismic damping systems include viscous fluid dampers or mechanical devices that limit the swaying of the building.
● Demolition and reconstruction : in extreme cases, when the risk to people's lives is too high or the costs of adaptation are prohibitive, it is possible to opt for demolition and reconstruction of the building according to modern seismic safety standards.
Types and techniques of reinforcement intervention
Obtain seismic improvement and/or adaptation for different structures
Seismic consolidation of masonry
Historical Italian buildings, often constructed with traditional techniques such as stone or brick masonry, have high levels of seismic vulnerability. Below are some of the most common structural consolidation methodologies applicable to masonry:
Resin or mortar injections
This technique is used to reinforce damaged masonry, especially when the original mortar has crumbled. The injection of resins or special mortars into the cracks and cavities improves the cohesion of the structure and restores its load-bearing capacity.
Reinforced concrete plating
This procedure consists of applying two sheets of reinforced concrete on the sides of the masonry, connecting them with transverse connectors. It is particularly effective for heavily damaged and inconsistent masonry. The reinforcement must be positioned in such a way as to guarantee continuity both vertically and horizontally.
Carrying out sewing interventions
In the presence of structural discontinuity between the different parts of the masonry, especially at corners or wall intersections, steel bars or composite fibers are used to connect the parts. This type of intervention serves to improve the stability and overall resistance of the structure.
Application of carbon fiber (FRP) or PBO (FRCM) reinforcements
Application of carbon fiber (FRP) or PBO (FRCM) reinforcements on the surfaces of the walls, improving the tensile strength and the ability to dissipate seismic stresses. This technique is very effective for historic buildings, as the intervention is relatively minimally invasive and visually discreet.
Consolidation interventions of arches and vaults
Specific parts of the walls, such as arches and corners, are subject to particular stresses. To reinforce these areas, steel or composite tie rods can be used, preventing localized detachments and collapses.
Prestressing chains and cables
To prevent the walls from tipping out of the plane, steel chains can be inserted. These elements are often integrated with other interventions, such as the reinforcement of the foundations and the injection of mortars or resins, creating an integrated consolidation system.
Seismic consolidation of reinforced concrete works
Reinforced concrete buildings , despite their greater resistance compared to traditional masonry, may present problems of degradation and/or cracking, due to construction errors or past seismic events. To improve the safety of these structures, various consolidation techniques are used, including:
Reinforcement of armor
Adding additional reinforcement, such as steel bars, increases the structural strength of reinforced concrete elements. This is especially useful in critical areas, such as beams and columns.
Epoxy resin injections
Cracks in concrete can be repaired by injecting epoxy resins, which restore the cohesion of the material and increase its resistance to future stresses.
Application of carbon fiber (FRP) or PBO (FRCM) reinforcements
The application of carbon fiber (FRP) or PBO (FRCM) reinforcements on reinforced concrete surfaces improves their load-bearing capacity and resistance. These types of reinforcement are an effective solution for increasing the resistance of structures while maintaining the sectional thicknesses almost unchanged.
Increase in the resistant section
A traditional method to improve the load-bearing capacity of structural elements is to increase their resistant section.
Increase in the resistant section
Insertion of metal carpentry elements, such as diagonals, to reduce the deformation field during seismic events.
Corrosion protection of armour
Reinforcement corrosion is a major problem in reinforced concrete structures. Preventive measures, such as applying protective coatings or using chemically modified concrete, can extend the service life of buildings.
AS Engineering and seismic safety: some of our projects
The protection of the Italian building heritage , in a context of high seismic risk , is a complex challenge that requires an integrated approach. Through the combination of accurate assessments, innovative technologies and continuous monitoring of structures, it is possible to mitigate the risk and guarantee the safety of both buildings and people. The advice of experts in seismic engineering is essential to address these challenges, and investing in seismic safety is a responsible choice that protects the future of our country.
Among the consolidation projects in which we have been protagonists, we can mention the intervention on a prestigious commercial-residential building in Via Solferino 25 in the heart of Milan , with the consolidation of arches and masonry vaults present in the basement and ground floors with the use of composite materials and the complete reconstruction of the wooden roof; as well as the seismic adaptation project of a building in a building complex hit by the seismic event of 2016 in the main urban center of Monsampietro Morico with the total reinforcement of the historic brick walls in addition to the reinforcement of the floors and the reconstruction of the roof in laminated wood.
Also noteworthy is the intervention at the former church in via S. Marta 20 in Vimercate with the conservative restoration of the historic church subject to monumental protection. The structural works project included important consolidations of both the masonry piers and the arches using PBO composites, consolidation injections with pressurized mortar and stainless steel bars, metal carpentry reinforcements, restoration of the historic wooden works as well as the reconstruction of the original bell tower .
In the industrial-commercial sector, we dealt with the seismic vulnerability and proposed seismic adaptation of the Revenue Agency Headquarters , Provincial Directorate of Venice for a total surface area of 32,500 m2 with the use of shock transmitter type devices and FRCM composite materials.
Thanks to our experience and the use of the most recent intervention methodologies, we can help preserve the Italian building heritage , ensuring safety and longevity of both historic and modern structures. For more information on our consulting services and seismic consolidation interventions, visit our dedicated pages .