Francesco Portioli

Francesco Portioli
University of Naples Federico II | UNINA · Department of Structures for Engineering and Architecture

PhD

About

101
Publications
43,231
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1,287
Citations
Additional affiliations
October 2018 - December 2021
University of Naples Federico II
Position
  • Professor (Associate)

Publications

Publications (101)
Article
A formulation for limit analysis of three-dimensional masonry structures modelled as rigid block assemblages is presented. A concave contact model is adopted for interfaces, using contact points located at the corners of the interface to represent interactions. A no-tension and non-associative frictional behaviour with limited compressive strength...
Article
A discrete element model is proposed for large displacement static analysis of dry-jointed masonry structures subjected to foundation settlements. The numerical model is a two-dimensional assemblage of rigid blocks interacting at no-tension, frictional contact interfaces with infinite compressive strength. The static contact problem associated to t...
Article
Full-text available
A unified formulation is presented for non-linear time history, static pushover and limit analysis of historic masonry structures modelled as 2D assemblages of rigid blocks interacting at no-tension, frictional contact interfaces. The dynamic, incremental static and limit analysis problems are formulated as mathematical programming problems which a...
Article
Full-text available
Displacement-based methods contained in recent standards for seismic safety assessment require the determination of the full nonlinear pushover curve for local failure mechanisms in historic masonry structures. This curve should reflect both the initial elastic behavior and the rigid body behavior after the activation of rocking. In this work, a ri...
Article
Full-text available
This paper deals with the vulnerability assessment of historic masonry structures subjected to settlements using rigid block modelling. A 2-D rigid block model with unilateral elastic contacts and finite friction is developed for the evaluation of the displacement capacity in the large displacement regime by push-down analysis. A variational formul...
Chapter
It is nowadays acknowledged that the minimum intervention principle shall guide any structural interventions on Cultural Heritage buildings. The enhancement of the structural capacity shall not result in a weakening of the values and the authenticity of the monument. Hence, the design of an efficient structural intervention has to be based on a cor...
Article
In this paper, the response of the rigid block under rectangular pulse excitation is investigated using two different modeling approaches and solvers. The first approach relies on the numerical integration of the differential equation of motion. The second approach is based on the formulation of the dynamic problem in terms of a special class of ma...
Article
Full-text available
Starting from funicular models, chain models and hanging membranes, the role of 3D physical models in optimized shape research is the basis of form-finding strategies. Advances in structural optimized shape design derive from the wide spread of special digital form-finding tools. The goal of this paper is to test and evaluate interdisciplinary appr...
Data
The repository contains the dataset related to the article "A variational rigid-block modelling approach to nonlinear elastic and kinematic analysis of failure mechanisms in historic masonry structures subjected to lateral actions" published in Earthquake Engineering & Structural Dynamics (2021). This companion document describes the content of the...
Article
In this paper, the structural response of a segmental dry-joint masonry arch subjected to increasing support displacements was investigated. The arch behaviour was analysed in the framework of large displacements using finite element (FE) and rigid block (RB) models, both based on a micro-modelling strategy. Once the two modelling approaches were v...
Presentation
Full-text available
The presentation shows how rigid block modelling can be conveniently used to predict the response of historic masonry structures when dynamic analysis, incremental static analysis (i.e. static pushover) and limit analysis are used for the assessment of collapse mechanisms under extreme events such as earthquakes and support movements. A discrete m...
Article
This paper presents an application of a simplified assessment approach to steel structures which takes into account sustainability requirements. The proposed approach is based on a time-dependent, multi-performance-based design methodology. The simplified procedure is organized in three main steps concerning the environmental conceptual design, the...
Article
Full-text available
This paper deals with the force-based assessment of collapse mechanisms and strengthening interventions of the historic masonry castle “Bussi sul Tirino” (Abruzzi, Italy) using rigid block limit analysis (RBLA). The structure, which is a fortified palace dating back to the 11th century, has experienced severe earthquakes over the centuries and was...
Chapter
The present work is focused on the analysis of the double-cap dome of St. Januarius Chapel, in Naples (Italy). Three different approaches based on the limit analysis for unilateral (no-tension) material has been applied to evaluate the dome stability. In the first approach, the overall stability of the dome has been investigated through a method of...
Article
Full-text available
A rigid block model is proposed for collapse mechanism analysis of three-dimensional historic masonry structures subjected to point live loads, seismic-induced lateral loads and settlements. The model is made of polyhedral rigid blocks interacting at no-tension, frictional contact interfaces and can be used to represent complex assemblages and bond...
Article
Full-text available
The paper is related to the assessment of collapse mechanisms of historic masonry structures suffering settlements induced by ground movements. Two numerical strategies are adopted in order to study the influence of the settled zone on the cracking of masonry buildings: a discrete rigid block model and a continuous homogenized model. The first appr...
Conference Paper
Full-text available
Masonry structures belonged to the Cultural Heritage suffered severe damages in the last decays due to the action of the settlement-induced ground movements. The researchers have been developing numerical tools for the vulnerability analysis and assessment of masonry structures subjected to settlements. Continuous, discrete and rigid block models w...
Code
LiABlock_3D is a rapid computational tool for limit analysis of masonry structures subjected to point live loads, seismic induced lateral loads and moving supports. Structures are represented as 3D assemblages of rigid blocks interacting at no-tension, frictional contact interfaces. LiABlock_3D is built as a standalone executable application fro...
Article
This paper investigates the structural behaviour of masonry vaulted staircases and the efficacy of different modelling strategies for the assessment of their structural safety. In particular, the present study focuses on the structural analysis of the masonry vaulted stairs of the medieval Santa Maria delle Vigne bell tower in Genoa (Italy), dating...
Article
Full-text available
The present study concerns the structural analysis of the masonry vaulted stairs of the Santa Maria delle Vigne bell tower in Genoa (Italy). The vaulted staircase systems are fully analysed in terms of technological and constructive details. The 3D geometric models are defined from laser scanner data. The structural analyses were carried out by usi...
Preprint
The present study concerns the structural analysis of the masonry vaulted stairs of the Santa Maria delle Vigne bell tower in Genoa (Italy). The vaulted staircase systems are fully analysed in terms of technological and constructive details. The 3D geometric models are defined from laser scanner data. The structural analyses were carried out by usi...
Conference Paper
Full-text available
The paper deals with the application of LiABlock_3D, a novel software tool developed at the University of Naples Federico II, to the case study of an historic masonry viaduct listed by UNESCO as World Heritage Site. LiABlock_3D analyses masonry structures under seismic lateral loads and automatically predict the potential failure modes of complex a...
Conference Paper
Full-text available
These simulations deal with the application of LiABlock_3D, a rapid computational tool developed by the Authors [1], for limit analysis of masonry structures subjected to point live loads, seismic induced lateral loads and moving supports. The software was previously validated against several experimental tests available in the scientific literatur...
Article
Full-text available
The aim of this paper is to show to what extent a simple constitutive model can adequately describe the collapse mechanisms of historic masonry structures under horizontal seismic loads. Referring to block masonry, the paper presents the formulation and the numerical implementation of a constitutive relationship for modeling masonry structures rega...
Conference Paper
This paper is devoted to the development of a discrete rigid block model for the assessment of dry-jointed masonry structures subjected to foundation settlements or spreading support in the large displacement regime. The numerical model is a two-dimensional assemblage of rigid blocks interacting at no-tension, frictional contact interfaces with inf...
Article
Full-text available
A simple variational formulation for contact dynamics is adopted to investigate the dynamic behaviour of planar masonry block structures subjected to seismic events. The numerical model is a two-dimensional assemblage of rigid blocks interacting at potential contact points located at the vertices of the interfaces. A no-tension and associative fric...
Conference Paper
Full-text available
In this paper a variational formulation for dynamic analysis is adopted to investigate rocking behaviour of masonry block structures under lateral loads. The model is composed of rigid bodies interacting at potential contact points located at the vertexes of the block interfaces. A no-tension and associative frictional behaviour with infinite compr...
Article
In this paper, a three-dimensional rigid body model is implemented to investigate the behaviour of masonry block structures subjected to foundation settlements. The structural behaviour is investigated formulating a limit analysis problem for the calculation of the base reaction and the associated failure mode once the settlement is introduced in t...
Article
Full-text available
The results of an experimental investigation carried out on steel splices bonded by (Carbon-Fiber–Reinforced Polymers) C-FRPs are presented in this paper. The main aim of the study is to examine the influence of different parameters on the type of failure and on the ductility of splices. Different configurations of the specimens were considered, in...
Article
Full-text available
A proper definition of the yield domains governing the frictional behaviour at contact interfaces is generally required to perform the limit analysis of 3D dry-jointed masonry block structures. However, the modelling of the actual behaviour of frictional contact interfaces under simultaneous normal and shear forces, torsion and bending moments is a...
Article
In this paper, we present a three-dimensional limit equilibrium analysis of an unreinforced brick masonry building. The structure under investigation is a one-room one-floor building that has been selected from a full-scale test carried out within the framework of a joint USA-Pakistan research project. The structural model of the building is an ass...
Article
Full-text available
The definition of the yield domains within limit analysis of 3D dry-jointed masonry block structures requires experimental and analytical investigation on the frictional contact problems. In this paper the torsion-shear interaction is experimentally investigated with reference to the single contact interface of a stack of two dry-jointed tuff block...
Article
In physical theory models, the hysteretic response of concentric braces is simulated by modelling the bracings with two nonlinear fibre-section beam–column elements connected together with an initial out-of-straightness imperfection (∆0). The width of such imperfection is the parameter governing the numerical prediction of the brace buckling. In th...
Article
Full-text available
Crucial to the limit analysis of 3D dry-jointed masonry block structures is a proper description of the constitutive laws that govern the frictional contact behavior. In this paper an extensive experimental investigation is carried out on a stack of two dry-jointed tuff blocks subjected to different loading conditions implying interactions among sh...
Conference Paper
Full-text available
In this paper, novel macro and micro-block modeling approaches are adopted for the assessment of the collapse load factor and failure mode of block masonry structures. The out-of-plane behavior of a masonry system composed of a façade wall connected with two sidewalls is investigated by means of limit analysis and some recurrent classes of mechanis...
Technical Report
Full-text available
La scheda di primo livello CARTIS è finalizzata al rilevamento delle tipologie edilizie ordinarie prevalenti nell'ambito di zone comunali o sub-comunali, denominate comparti, caratterizzate da omogeneità del tessuto edilizio. La scheda, sviluppata nell'ambito del progetto triennale ReLUIS DPC 2014-2016 nella linea "Sviluppo di una metodologia sist...
Conference Paper
Full-text available
Two classes of out-of-plane failure modes of a masonry system composed of a façade wall connected with two sidewalls are investigated. These involve rocking, sliding, torsion failure and combinations of them. A rigid-perfectly plastic model with dry contact interfaces governed by Coulomb failure criterion is assumed for masonry walls. The macro-blo...
Conference Paper
Full-text available
A rigid block model for three-dimensional limit analysis of masonry structures is used to investigate the behaviour of large scale masonry panels. A micro-modelling approach is adopted, based on the discretization of masonry units into blocks divided by frictional and tensionless contact interfaces. A convex contact formulation is used for interfac...
Article
Full-text available
A three-dimensional limit analysis model for masonry structures is presented. In the model the masonry is discretized as an assemblage of rigid blocks, which interact via no-tension contact surfaces with Coulomb friction. A concave contact formulation is adopted and an iterative solution procedure is used to allow the underlying non-associative fri...
Article
Full-text available
Atmospheric corrosion is a relevant problem for steel structures and components exposed in aggressive environment in case of poor and/or unfeasible maintenance and inspection during service life. As for thin-walled members, the corrosion hazard can be exacerbated due to the thin thickness of components and the coupled effect between corrosion and b...
Conference Paper
Full-text available
This paper presents a macro-block model and a simplified procedure for the assessment of the lateral capacity of in-plane loaded masonry walls made of rigid blocks and frictional joints. The macromodelling is based on the assumption that the failure involves a single crack which separates the structure in two macro-blocks and all the possible relat...
Article
Full-text available
In this paper, a masonry system composed of a façade wall connected with two sidewalls and subjected to out-of-plane loading is investigated within the framework of three-dimensional limit analysis. Two different modeling approaches, namely macro and micro-block models, are adopted. A rigid-perfectly plastic model with dry contact interfaces govern...
Article
An experimental study devoted to investigate the use of C-FRPs for repairing and strengthening lap shear hot-driven riveted connections is presented. Two set of tests were carried out: (i) double strap tests on both butt and lapped plates connected by C-FRP laminas; (ii) lap shear tests on riveted connections strengthened by C-FRP laminas. The effi...
Article
In this paper a rigid block model with cracking units and cohesive joints is developed for limit analysis of masonry structures using linear programming. The model is applicable to in-plane loaded unreinforced masonry block walls with regular textures and provides as output failure loads and collapse mechanisms. A simplified micro-modelling approac...
Article
Full-text available
This paper presents a macro-block model and a simplified procedure for the prediction of the collapse load and the failure mechanism of in-plane loaded masonry walls, with non-associative frictional contact interfaces. The macro-block modeling is based on the assumption that the failure involves a single crack where all the possible relative motion...
Article
In this paper, a formulation for limit analysis of three-dimensional masonry structures discretized as rigid block assemblages interacting through no-tension and frictional contact interfaces is developed. Linear and piecewise linearized yield functions are used for rocking, sliding and torsion failure. A simple yield condition has been defined to...
Conference Paper
A computer code based on a three-dimensional formulation for limit analysis of in-plane and out-of-plane loaded block masonry structures was developed. A rigid-perfectly plastic model with dry contact interfaces governed by cohesionless Coulomb failure criterion is assumed. Linear and linearized yield functions are used for rocking, sliding and tor...
Conference Paper
A rigid block model taking into account failure of the units and cohesive behaviour of the joints was developed for computational limit analysis of masonry panels. Masonry units are discretized into triangular rigid blocks separated by contact interfaces. Tensionless contact interfaces are used to model dry joints and cohesive contacts are introduc...
Conference Paper
Full-text available
In this paper, the design procedure and construction phases of a post-formed timber grid-shell are described. For form-finding and verification of structural safety, two dif-ferent numerical models were developed. A particle-springs system tool was used to get feed-backs on the allowable shape and element’s cross section without the use of scale mo...
Conference Paper
Full-text available
A computer code based on a three-dimensional formulation for limit analysis of in-plane and out-of-plane loaded blocky masonry structures was developed. A rigid-perfectly plastic model with dry contact interfaces governed by cohesionless Coulomb failure criterion is assumed. Linear and linearized yield functions are used for rocking, sliding and to...
Article
Full-text available
This paper summarises the results of a numerical study on the non linear response of steel concentric braced frames under monotonic and cyclic loads, using force-based finite elements with section fibre discretisation. The first part of the study is addressed to analyse the single brace response. A parametric analysis was carried out and discussed...
Conference Paper
Full-text available
The aim of this paper is to investigate the effects of contact interactions on local buckling of a built-up cold formed steel member assembled by mechanical fasteners. To this end a finite element model was developed. The numerical model was validated against the experimental results of four point bending tests carried out on three specimens with d...