# Francesco MarmoUniversity of Naples Federico II | UNINA · Department of Structures for Engineering and Architecture

Francesco Marmo

Professor (Associate)

## About

88

Publications

17,535

Reads

**How we measure 'reads'**

A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more

1,000

Citations

Introduction

Additional affiliations

December 2018 - May 2020

December 2013 - December 2018

## Publications

Publications (88)

In this paper, an alternative original analytical and numerical formulation is presented for the solution of a system of static and kinematic ordinary differential equations for curved beams. The formulation is represented here as being useful in the structural evaluation of arch structures and it is propaedeutic to be used in optimization framewor...

Creases are purposely introduced to thin structures for designing deployable origami, artistic geometries, and functional structures with tunable nonlinear mechanics. Modeling the mechanics of creased structures is challenging because creases introduce geometric discontinuity and often have complex mechanical responses due to the local material dam...

In the field of structural engineering, lightweight and resistant shell structures can be designed by efficiently integrating and optimizing form, structure and function to achieve the capability to sustain a variety of loading conditions with a reduced use of resources. Interestingly, a limitless variety of high-performance shell structures can be...

Los equinoides, conocidos como erizos de mar, son invertebrados que pueblan los mares desde finales del Ordovícico. Durante su evolución, se sometieron a una radiación adaptativa relevante que condujo a una variedad de formas y estilos de vida especializados. La mayor parte del éxito evolutivo de los equinoides se debe sin duda al empleo estratégic...

This study demonstrates the potentials of the use of bamboo strips for creating an active bending temporary corridor. In particular, this study presents preliminary results of an ongoing study aimed at designing and realizing a new original prototype active bending temporary corridor based on the use of bamboo strips. The main design goals are to o...

In this study, we explore the mechanics of a bigon and a bigon ring from a combination of experiments and numerical simulations. A bigon is a simple elastic network consisting of two initially straight strips that are deformed to intersect with each other through a fixed intersection angle at each end. A bigon ring is a novel multistable structure...

The paper addresses the theoretical framework and the numerical procedure developed to carry out the sectional analysis preliminary to the use of a recently formulated isotropic and homogeneous beam model consistently derived from the Saint Venant solid one.
Specifically, in order to ensure the equivalence of the new beam model with the 3D solid on...

The complex response characterizing elastomeric isolation bearings is reproduced by employing a novel uniaxial hysteretic model that has been recently formulated and successfully implemented in OpenSees. Such a novel OpenSees material model offers several advantages with respect to differential models typically available in commercial software prod...

According to Heyman’s safe theorem of the limit analysis of masonry structures, the safety of masonry arches can be verified by finding at least one line of thrust entirely laying within the masonry and in equilibrium with external loads. If such a solution does exist, two extreme configurations of the thrust line can be determined, respectively re...

The behaviour of magneto-electro-thermo-elastic materials is governed by a set of six differential equations in which the piezoelectric, the piezomagnetic, the magnetoelectric and thermal effects are coupled. Under the steady-state condition, this system of equations is homogeneous and can be rewritten as a set of uncoupled modified Laplace equatio...

A two-step form-finding strategy for determining the heights of a shell of a given plan-form is presented. The shell heights are determined in such a way that the structure can equilibrate applied loads by pure membrane actions. To this end, a set of algebraic equations are obtained by applying the finite difference method to the differential equat...

This book presents a range of research projects focusing on innovative numerical and modeling strategies for the nonlinear analysis of structures and metamaterials. The topics covered concern various analysis approaches based on classical finite element solutions, structural optimization, and analytical solutions in order to present a comprehensive...

The sites identified as "Industrial architecture" are a collection of structures, having a peculiar identity, which can still be used as a contemporary resource, worth being re-interpreted by means of urban projects of integrated and sustainable transformation urban font. In particular it is necessary to reactivate or create new processes, both pro...

We propose a numerical framework to study mechanics of elastic networks that are made of thin strips. Each strip is modeled as a Kirchhoff rod, and the entire strip network is formulated as a two-point boundary value problem (BVP) that can be solved by a general-purpose BVP solver. We first study the buckling behavior of a bigon, which consists of...

Shell and spatial structures are representative of some of the most efficient structural systems in which the optimized use of materials is combined with effective structural forms. The continuing development of analysis methods, design approaches and construction techniques of shell and spatial structures has resulted in an increasing interest to...

The endoskeleton of echinoderms (Deuterostomia: Echinodermata) is of mesodermal origin and consists of cells, organic components, as well as an inorganic mineral matrix. The echinoderm skeleton forms a complex lattice-system, which represents a model structure for naturally inspired engineering in terms of construction, mechanical behaviour, and fu...

The workshop offers lectures pertaining to the design, modelling, analysis, construction, and other aspects of the technology of all types of shell and spatial structures. Including tension and membrane structures, framed and lattice structures, gridshells and active-bending structures, shell roofs, tensegrity structures, pneumatic and inflatable s...

We present a systematic approach to the derivation of complete solutions for three-dimensional transversely isotropic elastic problems. The class of solutions derived in the paper is obtained by exploiting the entire kernel of the differential operator \(\mathcal {C}\) expressing the elastic equilibrium problem of transversely isotropic media. In p...

The paper illustrates the numerical procedure, based upon a Boundary Element (BE) approach, developed to efficiently evaluate the warping functions in the Saint Venant theory of beam-like solids having both compact and thin-walled sections. Specifically, Chebyshev nodes are selected as collocation points of the BE formulation associated with the re...

Nonlinear time history analysis represents the most appropriate structural analysis procedure to accurately analyze seismically base-isolated structures since their dynamic response is typically governed by a system of coupled nonlinear ordinary differential equations of the second order in time. The selection of a suitable phenomenological model,...

We discuss the energetic and geometric consistency of a one-dimensional (1D) beam model based on the Saint-Venant three-dimensional (3D) solution of a beam-like solid, with a focus on the effects associated with shear stresses. In particular we prove that a geometric model of the beam can be defined so as to provide the same elastic energy of the S...

Between the ’50s and the ’70s of the last century a class of analytical forms, the so called parabolic velaroid surfaces, were widely used to design thin reinforced concrete shells due to their ability to equilibrate design loads by pure membrane actions. These forms are obtained as an approximate analytical solution to the differential equation co...

Starting from the recent reformulation of the Thrust Network Analysis (TNA) developed by the authors, we further generalize the method in order to include triangular stress elements, used to model membrane thrusts within the analysis process. These elements substitute the classical network branches so that the correspondence between thrust stresses...

OpenSees (Open System for Earthquake Engineering Simulations) is an open source software conceived for the seismic analysis of structures. The source code is public to facilitate its wide diffusion and to be adaptable to the needs of users, who can also modify and extend default libraries in terms of materials, components, and algorithms. The main...

This paper presents a computational strategy that combines a novel rate-independent phenomenological model with an explicit time integration method to efficiently perform nonlinear dynamic analyses of non-stiffening hysteretic mechanical systems. The novel rate-independent model, developed by specializing a general class of uniaxial phenomenologica...

The bridge over the Basento river in Potenza, Italy, designed by Sergio Musmeci, is supported by a continuous double-curvature RC shell optimized to reduce bending forces. This 300 m long bridge can be considered as a unique representative example of pioneering research on the design and construction of optimized structures. First, the design proce...

Capacity domains of reinforced concrete elements, computed according to Eurocode 2 provisions, have been investigated from a probabilistic perspective in order to examine the variability of the failure probability over different regions of the domain boundary. To this end, constitutive parameters, such as limit stresses and strains, have been defin...

Through-the-thickness (TT) confinement of masonry and concrete panels by composite or steel reinforcements,
aiming at seismic retrofit of existing structures, has recently growth in popularity. However, structural design of
transversal reinforcements, modelled as an homogeneized material, is often performed by neglecting the cyclic
nature of seismi...

A procedure is presented for performing Eurocode 8-compliant spectral analyses of reinforced concrete structures by means of seismic response envelopes. To account for global torsion effects in the computation of the supreme envelope an algorithmic rotational response spectrum is defined. The presented strategy turns out to be particularly appropri...

We present a uniaxial phenomenological model to accurately predict the complex hysteretic behavior of bolted steel reinforced elastomeric bearings and unbonded fiber reinforced elastomeric bearings. The proposed model is based on a set of only five parameters, directly associated with the graphical properties of the hysteresis loop, leads to the so...

We illustrate the consistent derivation of a one-dimensional (1D) beam model from the Saint Venant three-dimensional (3D) solution of a beam-like solid that aims at the formulation of a 1D finite element able to reproduce the 3D elastic solution. The derivation is achieved by enforcing the equivalence between the 3D solid model and the 1D beam both...

We present a general formulation of a class of uniaxial phenomenological models, able to accurately simulate hysteretic phenomena in rate-independent mechanical systems and materials, which requires only one history variable and leads to the solution of a scalar equation for the evaluation of the generalized force. Two specific instances of the cla...

Starting from the recent reformulation of the Thrust Network Analysis (TNA) developed by the authors, we further generalize the method in order to include triangular stress elements, used to model membrane thrusts within the form-finding process. These elements substitute the classical network branches so that the correspondence between thrust stre...

The efficiency of a structure is strongly affected by its form and therefore its optimization is essential. The aim of this study is to investigate and discuss the form of the Musmeci bridge over Basento river in Potenza (Italy). This bridge can be considered a paradigmatic example of the form optimization of reinforced concrete shell structures. A...

We report on a historical study and on the evaluation of the structural performance of an innovative vaulting system developed in the 17th and 18th centuries. This peculiar construction technique, which employed clay hollow cylinders as construction blocks, was used to reduce erection times and costs as well as to guarantee several static and funct...

We derive the analytical expression of the Eshelby tensor field for inclusions of arbitrary polyhedral shape. The formula contributed in the paper is directly expressed as function of the coordinates defining the vertices of the polyhedron thus avoiding the use of complex variables and anomalies exploited in previous contributions on the subject. I...

We exploit a recent generalization of the Thrust Network Analysis (TNA) to analyse masonry structures of extremely complicated and audacious geometry such as helicoidal staircases. Actually, differently from available methods, based on ad-hoc solutions holding for each particular structure, the TNA allows for studying the equilibrium of structures...

The classical Eurocode-compliant ultimate
limit state (ULS) analysis of reinforced concrete
sections is investigated in the paper with the aim of
verifying if and how this well-established design
procedure can be related to plasticity theory. For this
reason, a comparative analysis concerning capacity
surfaces of reinforced concrete cross sections,...

A general procedure for the numerical solution of three-dimensional normal and tangential contact problems for non-conforming bodies of arbitrary shape is presented. The proposed procedure is based on the interpolation of known analytical solutions relating surface displacements of an elastic half-space subjected to pyramidal distributions of norma...

We address the Thrust Network Analysis (TNA), i.e. the methodology for modeling masonry vaults as a discrete network of forces in equilibrium with gravitational loads, first contributed by O’Dwyer and fully developed by Block and coworkers. Reducing the bias by the quoted authors in favor of a graphical interpretation of the method, we reformulate...

We generalize a recent application of the equivalent inclusion method, Jin et al. (2011), to derive the elastic field induced by a constant eigenstrain applied to an elliptic inclusion whose boundary is approximated by a polygon, the number of sides being assigned so as to recover the analytical values of the entries of the Eshelby tensor. The gene...

We outline a general methodology for proving the equivalence between several solutions available in the literature for the elastic problem of transversely isotropic materials. The proposed methodology is mathematically supported by a novel solution strategy yet arriving at the same expression of the displacement field contributed by Ding et al. (20...

The Eshelby tensor field is evaluated analytically for polygonal inclusions of arbitrary shape. The formula contributed in the paper is directly expressed as function of the coordinates defining the vertices of the polygon, thus avoiding the use of complex variables and anomalies exploited in previous contributions on the subject. It has been obtai...

We derive the analytical expression of the Eshelby tensor field for inclusions of arbitrary polygonal shape. Differently from previous contributions in the literature, the formula proved in the paper has a particularly compact expression since it is based on the analytical evaluation of integrals depending by lower exponents of the scalar product o...

The classical Cerruti problem of an isotropic homogeneous half-space subject to a concentrated load tangential to its surface is extended to cope with linear distributions of loads acting over a polygonal domain. The approach is based upon a generalized version of the Gauss theorem and recent results of potential theory which consistently take into...

We outline a general approach for extending the classical Boussinesq’s solution to the case of pressures distributed according to a polynomial law of arbitrary order over a polygonal domain. To this end we exploit a generalized version of the Gauss theorem and recent results of potential theory which consistently take into account the singularities...

We provide analytical formulas and design charts for computing displacements, strains and stresses in transversely isotropic half-spaces subject to linearly distributed vertical pressures. The domain integrals extended to the loaded region, resulting from the solution associated with a vertical point load, are first transformed into boundary integr...

By exploiting the theory of the response envelopes formulated by Menun and Der Kiureghian [Envelopes for seismic response vectors. I–Theory, J. Str. Engrg. 2000; 126(3); 467–473], an algorithmic approach for seismic analysis of reinforced concrete frames is presented. It aims to fill a gap between research on spectral analysis of structures and cur...

We present a procedure for the assessment of reinforced concrete structures in terms of seismic capacity based on the nonlinear pushover method. Structural systems containing shear walls are dealt with by adopting a newly developed reinforced shell element in which arbitrary distributions of steel reinforcement and nonlinear material behavior for b...

By integrating the classical Boussinesq expression we derive analytically the vertical stress distribution induced by pressures distributed with arbitrary laws, up to the third order, over polygonal domains. Thus, one can evaluate in closed form either the vertical stress produced by shell elements, modelling raft foundations by finite elements, ac...

We outline a general approach for evaluating the displacement, stress and temperature fields within an isotropic elastic half-space subject to a uniform heat source acting over an arbitrary region of its free surface. To this end we make systematic use of the Gauss theorem and exploit recent results in potential theory.

MATLAB function for the evaluation of displacements in a half-space due to
vertical load on a polygonal domain of the half-space surface.
Syntax:
U=LoPro(xyz,r,p,E,v)
Description:
U=LoPro(xyz,r,p,E,v) returns the three components of displacement at the
point of coordinate xyz=[x;y;z] of the half-space z>0, with Young modulus
E and Poisson ration...

It has been shown in a previous paper that the normal stress resultants for an arbitrary polygonal section endowed with a uniaxial elastoplastic law can be computed exactly by means of a general approach; it has been denominated fiber free as no fiber discretization of the section is required. The aim of this paper was to extend the fiber-free appr...

We present a family of algorithms for evaluating the ultimate limit state of composite and reinforced concrete (RC) sections of arbitrary polygonal or circular shape, either simple or multicell, subject to axial force and biaxial bending. All algorithms are based upon a secant strategy for computing the stiffness matrix used in the equilibrium iter...

Within the framework of flexibility formulations we present a frame element which enhances the performances of previously formulated elements in a threefold manner.
First, the analytical evaluation of the section integrals is carried out by means of the fiber-free approach, what avoids the use of the inaccurate fiber method; second, a variationally...

We present the preliminary results of a novel approach to the state determination of polygonal sections of arbitrary shape endowed with elasto-plastic uniaxial constitutive laws.
By means of a suitable application of Gauss theorem, we prove that the normal stress resultants can be computed analytically as sum of finite quantities evaluated solely a...

. A new strategy for in–situ testing of engineering structures is presented with the ultimate goal of providing real-time information on the structural behaviour during the test. The proposed procedure relies upon a probabilistic formulation and takes advantage of the Bayesian Network theory to account for uncertainties. An application is shown tha...

A secant approach is illustrated for the ultimate limit state (ULS) analysis of prestressed reinforced concrete sections subjected to axial load and biaxial bending in presence of softening stress–strain laws. The stiffness matrix and the resultant loads are evaluated analytically by a novel methodology, termed fiber-free, which represents a comput...

We illustrate a general methodology, based upon a suitable application of Gauss theorem, to evaluate the vertical stress within a homogeneous isotropic elastic halfspace due to pressures linearly distributed over polygonal domains of arbitrary shape. Charts and tables are provided in order to facilitate the practical application of the results cont...