Paolo Formichi

University of Pisa | UNIPI · Department of Civil and Industrial Engineering

Inspired by the Alan G. Davenport Wind Loading Chain, first a uniform format for the modelling of climatic actions of snow, wind, thermal actions and atmospheric icing actions is presented in the form of a Climatic Action Loading Chain (CALC). The definition of the complete probabilistic loading chain is discussed providing the basis for a more rel...

As a consequence of climate change impact, a significant variation in terms of temperature, atmospheric humidity, and carbon dioxide concentration levels is happening. This condition leads to several negative effects on the safety and the life cycle of existing concrete structures, such as the increase in the rate of material degradation, due to co...

In standards for structural design, models for snow loads on flat roofs generally provide the basis for determination of snow loads on any roof shapes. They are typically derived from ground snow loads and the predicted effects of exposure of flat roofs primarily due to wind, often conveyed through the exposure coefficient. The paper provides backg...

The assessment of seismic performance of existing masonry structures is a key aspect for the risk mitigation strategies of existing buildings and preservation of historical heritage. The increasing availability of modelling approaches for the assessment of seismic response of masonry structures calls for the need of verifying their reliability and...

Refined non-linear static or dynamic analyses are increasingly used to assess the behavior of new and existing reinforced concrete structures. To perform these analyses, an adequate knowledge of the force–displacement, bending moment–curvature, and bending moment–rotation curves of relevant parts of structural members is needed, and modeling the bo...

The evaluation of seismic performance of existing masonry structures is a fundamental issue for the preservation of cultural heritage in general and of historical buildings in particular, even in view of the adoption of suitable policies for risk mitigation. To assess the seismic performance of existing masonry buildings, several refined push-over...

The evaluation of seismic vulnerability of existing masonry building is a first fundamental step for the preservation of historical buildings in seismic prone area.

Lightweight roofs are extremely sensitive to extreme snow loads, as confirmed by recently occurring failures all over Europe. Obviously, the problem is further emphasized in warmer climatic areas, where low design values are generally foreseen for snow loads. Like other climatic actions, representative values of snow loads provided in structural co...

Evaluation of effects of climate change on climate variable extremes is a key topic in civil and structural engineering, strongly affecting adaptation strategy for resilience. Appropriate procedures to assess the evolution over time of climatic actions are needed to deal with the inherent uncertainty of climate projections, also in view of providin...

In consideration of the high vulnerability of the built environment, the assessment of seismic behavior of existing masonry buildings is a key topic in view of their retrofitting and reuse. Because masonry’s behavior depends on complex nonhomogeneous, anisotropic, asymmetric, and nonlinear properties, the definition of suitable mechanical models is...

Since extreme values of climatic actions are commonly derived assuming the climate being stationary over time, engineering structures and infrastructures are designed considering design actions derived under this assumption. Owing to the increased relevance of the expected climate change effects and the correlated variations of climate actions extr...

The assessment of existing structures and infrastructures is a primary task in modern engineering, both for its key economic significance and for the extent and the significance of the built environment, nonetheless operational rules and standards for existing structures are often missing or insufficient, especially for masonry constructions. Exist...

The evaluation of the shear behavior of masonry walls is a first fundamental step for the assessment of existing masonry structures in seismic zones. However, due to the complexity of modelling experimental behavior and the wide variety of masonry types characterizing historical structures, the definition of masonry’s mechanical behavior is still a...

In modern structural codes, the reference value of the snow load on roofs is commonly given as the product of the characteristic value of the ground snow load at the construction site multiplied by the shape coefficient. The shape coefficient is a conversion factor which depends on the roof geometry, its wind exposure, and its thermal properties. I...

p>The assessment of climate change impacts is becoming increasingly relevant for many sciences and engineering disciplines. In this context, climate change may significantly affect the design of new structures and infrastructures as well as the long-term reliability of existing ones designed under the assumption of stationary climate. A methodolog...

Historical and cognitive investigations supported by in-situ and/or laboratory tests are needed for a robust reliability assessment of existing structures. Indeed, an adequate knowledge of material properties and their statistical description is the basis for carrying out accurate reliability analyses and verifications on the investigated structure...

Time-dependent reliability assessment is a crucial aspect of the decision process for rehabilitation of existing reinforced concrete structures. Since the assessment strongly depends on degradation of materials with time, the paper focuses on the influence of corrosion in reinforcing steel on time-reliability curves of relevant reinforced concrete...

Climatic loads on structures are commonly defined under the assumption of stationary climate conditions; but, as confirmed by recent studies, they can significantly vary because of climate change effects, with relevant impacts not only for the design of new structures but also for the assessment of the existing ones. In this paper, a general method...

The set-up of common approaches for the elaboration of climatic actions maps across borders of neighbouring countries in Europe is one of the most relevant and challenging objectives towards further harmonization of structural Eurocodes. EN1991-1-3 is the part of Eurocode 1 dealing with snow loads on structures; its Annex C provide guidance for the...

In the mid-term future, climate change could determine significant alterations of the frequency and magnitude of climate extremes, so affecting the design of new structures and infrastructures, and the reliability of existing ones designed according to the provisions of present or past Codes. In this work, a Bayesian hierarchical model for the char...

p>As consequence of global warming extreme weather events might become more frequent and severe across the globe. The evaluation of the impact of climate change on extremes is then a crucial issue for the resilience of infrastructures and buildings and is a key challenge for adaptation planning. In this paper, a suitable procedure for the estimatio...

p>In nonlinear static analysis of masonry buildings, the hysteric behaviour of masonry walls is commonly idealized through a bi-linear resistance envelope defined by the lateral stiffness of the wall, the ultimate shear resistance and the ultimate inter-storey drift. Therefore, it becomes fundamental to properly set the modulus of elasticity and sh...

p>Masonry structures represent a large part of existing buildings. As confirmed by the damage caused by recent seismic events, the assessment of seismic performance of existing masonry building is then a critical issue in Countries exposed to seismic risk. Moreover, common methods of analysis based on non-linear static approach are significantly in...

p>The impact of climate change on climatic actions could significantly affect, in the mid-term future, the design of new structures as well as the reliability of existing ones designed in accordance to the provisions of present and past codes. Indeed, current climatic loads are defined under the assumption of stationary climate conditions but clima...

Climate change could significantly affect climatic actions, so influencing not only existing structures, designed in accordance to the provisions of past Codes, but also updating of structural Codes. In the paper a new probabilistic technique for bias correction and downscaling of climate projections is presented to assess uncertainties in the futu...

It is often assumed that, as a consequence of global warming, a reduction of snow load on the ground should be expected. In reality, snow load is often depending on local orographic situations that can determine an increase of its height, even when the average snow height over the surrounding areas is reduced. Large snow loads on roofs during the w...

In the assessment of seismic performance of masonry buildings, the proper definition of mechanical parameters of masonry, the shear modulus in particular, is a critical issue. Moreover, considering that existing buildings are characterized by several masonry types, depending on the material as well as on the texture, mechanical parameters can vary...

In seismic zones, suitable procedures to assess the seismic vulnerability of existing buildings are necessary also in view of optimal planning of interventions. Starting from the agreement between the Municipality of Florence and the Department of Civil and Industrial Engineering of the University of Pisa, a research program is ongoing, devoted to...

The results of material acceptance tests or in-situ tests are a valuable source of information for reliability assessment of existing structures. Huge secondary databases of test results are usually available, coming from different sources, but individual results are often not associated to a given population, so their statistical analysis is a com...

A general procedure to evaluate future trends in snow loads on structures is illustrated aiming to study influences of climate change at European scale, to assess its impact on the design of new structures as well as on the reliability levels of existing ones, also in view of definition of updated snow maps for new generation of Eurocodes. Starting...

The effect of climate change on climatic actions could significantly affect, in the mid-term future, the design of new structures actions as well as the reliability of existing ones designed according the provisions of current codes, which are derived from past observations under the assumption of stationary climate conditions. An original techniqu...

Failure or malfunction of complex engineered networks involves relevant social and economic aspects, so that their maintenance is of primary importance. In assessing the reliability of such networks, it should be duly considered that they are a whole made of different parts, and that some of these individual parts or structures are often crucial to...

p>The effect of climate change could significantly affect, in the mid-term future, climatic actions and then the design of new structures as well as the reliability of existing ones, designed according the provisions of current or past codes. In this wok, a suitable procedure to derive snow loads on ground under non-stationary climate conditions is...

The paper explores three stochastic inverse methods based on a functional approximation of the system response: the Markov Chain Monte Carlo method, the Polynomial Chaos Expansion based Kalman Filter, and the parameter update with the Minimum Mean Squared Error estimator. The algorithms were implemented to update the probability distribution functi...

p>The aim of the present study is to set up a general procedure to predict future trends in snow loading on structures, taking into account the impacts of climate change according different emissions’ scenarios, modelled at a global scale. The procedure is validated against high quality data series collected for at least 50 years at weather station...

Support to the implementation, harmonization and further development of the Eurocodes

Activities for promotion of policies for sustainable construction in the Balkan region. Guidance for countries adopting the Eurocodes. State-of-the-art material to elaborate maps for seismic and climatic actions for structural design. Experience of the non-EU Balkan countries on elaboration of these maps. Elaboration of maps for climatic and seismi...

The Leonardo da Vinci Project, “Innovation Transfer in Risk Assessment and Management of Aging Infrastructures”, CZ/13/LLP-LdV/TOI/134014, addresses the urgent need to train students, young engineers and professionals in the assessment of existing infrastructures. The future of the construction industry lies in moving from new constructions towards...

The Leonardo da Vinci Project, “Innovation Transfer in Risk Assessment and Management of Aging Infrastructures”, CZ/13/LLP-LdV/TOI/134014, addresses the urgent need to train students, young engineers and professionals in the assessment of existing infrastructures. The future of the construction industry lies in moving from new constructions towards...

Refined non-linear static or dynamic analyses of reinforced concrete structures require the know-ledge of the actual force-displacement or bending moment-rotation curves of each structural member, which depend on the crack widths and on the crack pattern, and after all on the slip be-tween concrete and reinforcing steel. For this reason the definit...

The classical approach considering perfect bond between steel rebars and concrete is often unsuitable in refined analysis of reinforced concrete elements, as it leads to significant errors in the estimate of the actual stiffness. For this reason more refined procedures have to be considered. In the paper a numerical algorithm is illustrated, able t...

In EN1990, action effects in persistent and transient design situations are to be derived according to appropriate combinations of actions. Three different sets can be chosen alternatively in the National annex: expression 6.10 or the most adverse between expressions 6.10a and 6.10b or the most adverse between expressions 6.10a modified and 6.10b....

A recent scientific research, carried out by eight European institutions, produced a map of the ground-snow-load characteristic value, by using the observations at 2600 meteorological stations placed all over the European territory. Such a map represents the result of the most advanced study now available, since for the first time common methods we...

Die große Anzahl der Temperaturmessungen, die über einen Zeitraum von vier Jahren am Schiefen Turm von Pisa vorgenommen wurden, werden unter Verwendung statistischer Methoden ausgewertet und mit den Ergebnissen der theoretischen Berechnungen mittels FEM verglichen. Hierbei werden die instationären Randbedingungen, die die stündlichen Veränderungen...

The main results of a prenormative research programme on snow loads, sponsored in 1996 by the European Commission, are presented. The research work, to which eight European scientific institutions took part, addressed the determination of ground and roof snow loads for ultimate and serviceability limit states verifications. European regulations reg...