National Projects

Masonry structures, including historic buildings, are socially and economically vital to our communities and represent the vast majority of the European built patrimony. Many of these buildings are in a poor state of preservation due to material ageing and degradation and in the Mediterranean Basin they are severely exposed the seismic hazard. The preventive conservation of historic buildings across the whole Europe is therefore an urgent priority, which demands for appropriate Structural Health Monitoring (SHM) systems that link the field observation of the in-service response of a structure to its structural safety. To-date, SHM is yet to be broadly implemented in masonry structures because off-the-shelf sensors are hardly scalable to complex buildings, have limited durability and are limited in number and localization by transmission issues, difficulty of access and high costs. Multifunctional strain-sensing and damage-sensing structural materials are emerging as a potential solution to monitoring challenges and could substantially impact the field of SHM in the near future. In particular, recent advances in Nanotechnology have led to the development of so-called smart concretes that are electrically percolating cement-based composites with piezoresistive properties, based on the incorporation of carbon-based micro- and nano-fibers into cementitious matrices. Their strain sensitivity originates from the property of the materials to exhibit variations of their internal resistivity and impedance, under variations of their mechanical deformation. Recently, the PI has developed smart concrete applications based on the use of Multi-Walled Carbon Nanotubes (MWCNT) as conductive doping and has proposed the application of a similar concept in the field of masonry structures, through the introduction of smart bricks, that are clay bricks doped with stainless steel microfibers able to provide an electrical output proportional to their state of strain. Despite a rich literature in recent years, both technologies of smart concretes and smart bricks can still be considered in their development stages, with the latter being indeed at its very birth. Among bottlenecks and aspects that need further investigations are: material fabrication, electrode type and deployment, measurement techniques, electromechanical modeling and signal processing for automated earthquake-induced damage identification. SMS-SAFEST aims to develop a radically new paradigm for SHM of existing masonry structures by proposing the novel technology of smart masonry. This is a combination of smart mortar layers and smart bricks, placed at selected critical locations within a masonry structure during a retrofit intervention. During masonry repointing, old mortar will be removed and locally smart mortar will be infilled, after installation of hidden electrodes. Similarly, old bricks will be locally substituted with smart bricks. Smart masonry will provide existing structures with the ability to self-assess their structural conditions after an earthquake, providing immediate information about structural safety. Smart conductive mortar layers and smart bricks will have specialized functions in smart masonry. Conductive mortar layers will allow to localize cracks crossing them as local changes in electrical resistance of the mortar, using an array of electrodes hidden in the inner core of the masonry and not visible from the facade. Smart bricks will provide an electrical output proportional to their volumetric strain and this information will be automatically processed for global structural assessment and damage detection. A damage will be identified using advanced data science tools, on the basis of changes in dead-loads-induced strain outputted by smart bricks and on the basis of cross-comparison of the outputs of smart bricks. The first part of the project will focus on the development of the radically new technology of smart masonry with a focus on fabrication procedures and measurement setup. The second part of the project will be devoted to modelling and signal processing aspects. Demonstration experiments on prototype structural models will be finally performed in the third part of the project after optimization of procedures for application of smart masonry to existing structures.

Funding source: Italian Ministry of University and Research, from 2024 to 2029, Amount M€1.5, Grant No: FIS00001797.
Principal Investigator: Prof. Filippo Ubertini.

Website: SMS-SAFEST

The Project proposes the sustainable development of piezoresistive and piezoelectric smart concrete composites for Structural Health Monitoring (SHM) and energy harvesting. The main goal is to realize reinforced concrete structures, including buildings, bridges, and others, with innovative technologies that can self-detect their structural integrity during operating conditions. Piezoresistivity will be achieved by adding carbon-based conductive inclusions to cementitious matrices. Piezoelectricity will be obtained by employing graphene oxide as an electrically conductive filler.

Main objectives:

• Optimization of the production process of piezoresistive and piezoelectric concrete composites, including the selection of the most suitable electrically conductive fillers and the use of 3D printing;
• Development of electromechanical models that reproduce the response of the smart concrete composites and monitoring strategies based on the use of strain measurements from smart composites;
• Validation of the proposed innovative technology on a medium-scale structural element subjected to controlled damage of increasing intensity.

Funding source: Italian Ministry of University and Research, from 2022 to 2025, Amount €XXXXX, Grant No: ECS00000041.
Principal Investigator: Prof. Filippo Ubertini.

Website: Vitality UniPG

The safety and resilience of existing buildings in urban centres are key priorities for protection and sustainable development of society, according to the Sendai Framework for Disaster Risk Reduction 2015–2030, EU Research & Innovation Programme 2021–2027 “Horizon Europe”, Italian National Recovery and Resilience Plan, and Italian National Research Programme 2021–2027. The achievement of such goals is undermined by several major issues, such as: (i) increasing exposure of buildings to natural, accidental and man-made hazards; (ii) growing vulnerability of building structures due to aging and deterioration; (iii) rising accumulation of world population in urban centres; and (iv) strong interaction between people, buildings and infrastructures. In last decades, the occurrence of many disasters has further remarked all above-mentioned issues, highlighting an urgent need for unified approaches encompassing safety and resilience across multiple scales, moving from individual buildings to urban areas. The FAIL-SAFE project is framed within Horizon Europe’s Cluster 3 “Civil security for society” and aims at developing a multi-scale framework for near-real-time (NRT) performance assessment of existing buildings subjected to a failure event via integration between simulation, structural health monitoring (SHM), and novel data science methods and digital technologies related to Industry 4.0. NRT simulation will involve both structure-specific and urban scales, accounting for different levels of information (and hence uncertainty) on the failure event and building characteristics, both intra-building and inter-building damage propagations, and impact on systemic efficiency and recovery of the urban area. Structural robustness of existing buildings under a variety of failure scenarios will be assessed via several computational strategies with different levels of sophistication, considering degradation phenomena and debris accumulation outside buildings. The project will focus on masonry and reinforced concrete (RC) structures, which are the majority of existing buildings in urban areas, particularly in Europe. A multi-scale approach will also be applied to SHM, leading to urban-scale structural health monitoring where hybrid data, data-driven algorithms and high-performance cloud computing will be used to support rapid decision-making for loss mitigation and resilience enhancement. Urban resilience will be evaluated using hybrid social-physical networks automatically generated from geographical information systems. The methodology and outcomes will be tested against several documented past disasters involving progressive collapse of buildings and its impact on urban areas. The FAIL-SAFE project involves 3 research units with expertise in the above-mentioned topics: Università degli Studi di Napoli Federico II, Università degli Studi di Perugia and Università degli Studi di Parma.

Funding source: Italian Ministry of University and Research, from 2023 to 2025, Amount €296.973, Grant No: 2022JFXE95.
Principal Investigator: Prof. Fulvio Parisi.

Italian transport infrastructures are characterized by road networks that show important critical issues. Many bridges dates back to the post-World War II and often their standards are far away from those required by current design codes. In addition, traffic loads increased more and more, and traffic limitations are often implemented as temporary safety measures, while maintenance operations are limited, so the degradation processes can detrimentally evolve resulting in a reduction of the performances of structural components. Such a consequence can be particularly relevant for concrete bridges with post-tensioned deck, where the cables are not directly visible, therefore their state of conservation is not easily assessed with visual inspections only. All these aspects lead to serious problems for the transportation system, as recently reminded by several bridge collapses. Assuming existing bridges as key components of road networks, the proposal aims at studying the time evolution of their reliability by developing a comprehensive probabilistic framework including: (a) uncertainties in the system knowledge, (b) evolution of progressive degradation, (c) evolution of service actions and conditions. Research focuses on concrete bridges with post-tensioned deck. In previous studies, reliability assessment has been mainly studied as a “static” problem, and the “time dimension” has been usually neglected or included as an independent parameter (e.g. repeated analyses), without considering the interaction of different causes of evolution and without fully exploiting the uncertainty reduction due to monitoring and testing programs. The proposal aims at providing a prediction model to support the managing system, ensure an adequate reliability level during the lifetime and optimize the maintenance/restoration planning. The problem is approached by a framework with original contents, where the evolution over time of the system is described as a Markov process involving two transition operators, the former related to the evolution of the basic variables, and the latter related to model updating and knowledge evolution. This way it is possible to evaluate how such different aspects reduce the variability of parameters and consequently influence the prediction of the residual life. Knowledge advancements are expected about: methods for time-dependent reliability assessment of bridges with post-tensioned deck, evolution models for traffic actions and prestressing system effectiveness, procedures and confidence levels of testing of prestressing systems, Bayesian model updating and machine learning techniques in prestressing action modelling. To approaches such an inter-disciplinary topic, a partnership involving researchers with different and complementary expertise has been organized. The group includes UniCAM (Bridge Engineering, Reliability analysis), UniPI (Bridge actions, Inspection Procedures) and UniPG (Structural Health Monitoring, Model updating).

Funding source: Italian Ministry of University and Research, from 2023 to 2025, Amount €299.983, Grant No: P20223Y947.
Principal Investigator: Prof. Andrea Dall'Asta.​

DETECT-AGING aims at synergistically combining structural modelling and Structural Health Monitoring (SHM) in a novel multidisciplinary approach to quantify effects of degradation on structural safety of built cultural heritage against natural or anthropic risks. Among the huge variety of cultural heritage assets, attention will be focused on historical masonry palaces.

Effects of degradation of materials, connections, and previous retrofit interventions (e.g. corrosion of metal tying bars or meshes inserted in reinforced plasters) will be evaluated. A multiscale approach will be considered by assessing degradation impact from the scale of materials up to that of whole structures. Although the complexity of cultural heritage assets often leads to the adoption of 3D Finite Element Models (FEM), also popular in the SHM community, a precise target of DETECT-AGING is evaluating the potential of Equivalent Frame (EF) modelling techniques. EF is an acknowledged modeling strategy for seismic analysis, but its ability to reproduce operational responses is still debated and requires specific methodological developments. Nevertheless, high computational efficiency of EF models is quite appealing since the computational effort required by FEM is not always viable in engineering practice and for real-time performance assessment. DETECT-AGING will therefore develop a new methodology that shall meet two main targets: i) ease of transfer information on mechanical behavior from one scale to another, through coherent variables; ii) direct applicability to practice-oriented management tools. The proposed approach will consider the various sources of uncertainties (epistemic and aleatory) affecting the structural assessment process, in relation to demand and capacity models, as well as to properties of materials and geometric data. Their inclusion into the proposed methodology is therefore crucial for the success of DETECT-AGING, that will be done by using probabilistic approaches and logic tree techniques. SHM systems have the potential to reduce both epistemic and aleatory uncertainties and support pro-active risk management. Building on the information provided by SHM systems, stakeholders and operators can schedule structural interventions when reaching a specific threshold related to a known performance loss (preventive conservation or condition-based maintenance), rather than inefficiently intervene on a periodical basis or after the harmful event (time-based and breakdown maintenance). Properly selecting performance thresholds is the core of SHM-based preventive conservation. To this aim, representative engineering parameters will be defined for describing structural response at different scales and for predicting damage effects. Performance thresholds will be established using information from field measurements (monitoring system) and parameters related to in situ measurements. The developed SHM systems shall meet the dual objective: (i) to reveal the occurrence of a degradation-induced damage through automated analysis of structural response, by achieving an effective fusion of heterogeneous, global (e.g. vibration modes) and local (e.g. crack openings), dynamic and static response data. This will be pursued through long-term monitoring strategies, with appropriate compensation of environmental effects and using permanent sensor networks. Optimization of such networks will derive from the characterization of the effects of degradation by multiscale structural models. (ii) to locate degradation-induced damage in certain portions of the structure, by relying upon denser sensor networks in most critical structural parts and by using model-based a priori estimated scenarios of actions. Objective (ii) is rather more ambitious than (i), as reliable techniques for damage localization in complex masonry structures are yet to be established. DETECT-AGING will therefore go beyond the state-of-the-art in improving the predictive capability of SHM systems. Laboratory tests will be carried out on substructures subjected to mechanically induced or simulated degradation during the construction phase. According to the global multiscale approach of the project, some small-scale tests will be conducted to calibrate/check variations in structural parameters at the element scale, while further larger-scale tests will be conducted on masonry walls with single opening (two masonry piers with a spandrel) under in-plane and out-of-plane loadings and on a 3D mock-up. This phase will represent the validation of the proposed methodology, whereby monitoring network and structural numerical models will be tested in the case of controlled degradation scenarios. Finally, monitoring data of actual monumental buildings, monitored within the activities of previous or side projects, will be used to verify response modifications that can be revealed by SHM as a function of degradation simulated by structural models.

Funding source: Italian Ministry of University and Research, from 2019 to 2023, Amount €122.000 (UniPG), Grant No: 201747Y73L.
Principal Investigator: Prof. Gian Piero Lignola.​

The Italian transport infrastructures are characterized by road networks that show important critical issues, that where unfortunately enlightened by some recent catastrophes. These issues are generally connected to the natural degradation of the material and components with the time, added to lack of structured maintenance planes and to the fact that many bridges constituting the transport system date back to the post-World War II and often their standards are far away from those required by current design codes. In this framework, the Italian guidelines for the maintenance of bridges propose a process for the risks’ assessment of the infrastructures. Focusing on the structural risk, this approach is easily applicable to most of the construction techniques where the conservation status and the possible damages are easily detectable by visual inspections, but otherwise gets more complicated. In the wide variety of material, structural typologies and construction techniques, many bridges are characterized by Post-Tensioned (PT) concrete decks. This technique has been largely adopted in the last century, carrying many advantages such as quick construction process, moderate cost and reduction of scaffolding and shuttering works. On the other hand, it also has some critical issues as the degradation process of post-tensioned cables, hidden by the injection duct, is mainly related to execution errors in the injection itself with grout (a grout-free section of tendons is greatly exposed to the risk of corrosion), or in their waterproof sealing, or in bridge drainage. The related cable corrosion in combination with the tension stresses can lead to a fast loss of resisting area section of the steel. Consequently, the degradation process could indeed be the main element influencing the final reliability of the bridges. The proposal aims at developing a comprehensive process to assess the actual reliability of existing post-tensioned concrete bridges, by the analysis of all the key aspects for the evaluation of the reliability (material properties, traffic load, testing and survey process) and their related uncertainties. Probabilistic models of them will be developed to proper calibrate the common safety format of partial factor methods to achieve specific reliability with a proper confidence level. Finally, a method for the evaluation of the residual life of post-tensioned bridges will be integrated considering the degradation processes typical of such structures. Moreover, the continuous flux of data from the monitoring system can be used to assess the traffic load actions and the time-dependent reliability, increasing also the knowledge about the bridge and consequently reducing the uncertainties related. Consequently, integrating the degradation models in the safety check it is possible to monitor the residual working life and define a fair decision-making process on the bridges. The entire process will be checked and tested on a set of case studies.

Funding source: Fabre Consortium, from 2022 to 2024, Amount €27724 (UniPG). Principal Investigator: Prof. Andrea Dall’Asta.

Funding source: Piano di Sviluppo Rurale – Regione Umbria, from 2021 to 2023, Amount €24000 (UniPG). Principal Investigator: Prof. F. Ubertini.

Funding source: Italian Ministry of University and Research, from 2020 to 2022, Amount €400000 (UniPG). Principal Investigator: Prof. V. Gusella, Prof. F. Ubertini.

About 60% of Italian buildings, including those belonging to the historic heritage, are made of brick masonry. The preventive conservation of such a built patrimony against aging and natural hazards is therefore an urgent priority. Structural Health Monitoring (SHM) is a widely accepted method for preventive conservation, whereby the condition assessment of civil structures is automated by linking the experimental observation (sensor data) of their in-service response to their structural integrity (damage diagnosis and health prognosis). SHM can lead to enormous potential savings but is yet to be broadly implemented because of limitations in off-the-shelf sensing technologies, related to their durability, installation, cost, transmission, and processing. Recent advances in Nanotechnology are rapidly providing innovative solutions for SHM, including the development of smart composites with the functional properties of being strain- and damage-sensitive. While a lot of research efforts have been carried out in recent years to develop strain-sensing nanocomposite cement-based materials for applications to concrete structures, a strain-sensing structural masonry has never been proposed. SMART-BRICK aims to propose and develop the radically new "smart clay brick", that is, a piezoresistive nanocomposite clay brick able to sense its internal state of strain. This technology has the potential to provide an effective innovative solution for SHM of masonry structures, overcoming the limits of existing sensing solutions. The vision is that of inserting a few smart bricks at critical locations inside the structure, so as to carry out the following tasks: (i) monitoring the state of stress in the masonry, (ii) detecting active failure mechanisms caused by an earthquake or other exceptional loading events and (iii) carrying out vibration-based monitoring. The smart clay brick will be obtained by doping a classic clay brick with appropriate conductive micro- or nano-fibers. Its strain sensitivity will thus originate from the property of the material to exhibit variations of its internal resistivity, under variations of its mechanical deformation. Cracks passing through the smart brick will be detected as interruptions of the conductive paths. SMART-BRICK is a breakthrough project that aims to address various technological and theoretical challenges. Achieving good nanoparticles' dispersions is one of these challenges, which, compared to cement-based composites, is even more complicated in clay bricks, where nanoparticles need to be dispersed in raw clay with controlled humidity at first and then kept stable after burning at about 1000 °C for hours. Other relevant challenges concern hiding point electrodes to keep good aesthetical results, as well as investigating toxicity, environmental impact, cost, durability, color, electromechanical modeling, quality of output signal and its dependence upon environmental conditions.

Funding source: Italian Ministry of University and Research, from 2017 to 2020, Amount €106.962, Grant No: 2015MS5L27.
Principal Investigator: Prof. Filippo Ubertini.

Funding source: Cassa di Risparmio di Perugia Foundation, 2014 Grant No: 2014.0266.021

Funding source: Cassa di Risparmio di Perugia Foundation, 2016 Grant number 2016.0028.021