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This paper adopts the use of steel frames around existing openings as a low-impact seismic retrofitting strategy for unreinforced masonry structures (URM). Although elastic steel frames have been commonly adopted for strengthening masonry walls in case of the realization of new openings, the use of elasto-plastic frames has been proposed only recently. This study adopts the application of low-resistance ductile steel frames on the openings of existing masonry buildings as a low-impact retrofitting strategy. The adopted low-invasive solution possesses the advantage of increasing the in-plane resistance of the masonry wall, improving the displacement capacity, introducing additional energy dissipation under dynamic loadings, and providing a confinement effect on the adjacent masonry piers. An original aspect of the present paper is related to the adopted numerical method for modelling the presence of the steel frames around the openings. Namely, a Discrete Macro-Element Method (DMEM), which allows an efficient and reliable simulation of the involved collapse mechanisms of the masonry walls interacting with the frames, has been adopted. After the validation of the numerical approach, through a comparison with experimental results already reported in the literature, the low-impact strategy has been applied on a benchmark known as the “via Martoglio building”. The obtained results suggest that this low-impact retrofitting strategy can be successfully proposed for URM buildings and can be efficiently modelled by means of the DMEM.
Giuseppe Occhipinti; Francesco Cannizzaro; Salvatore Caddemi; Ivo Caliò. A Discrete Macro Element Method for Modelling Ductile Steel Frames around the Openings of URM Buildings as Low Impact Retrofitting Strategy. Sustainability 2021, 13, 9787 .
AMA StyleGiuseppe Occhipinti, Francesco Cannizzaro, Salvatore Caddemi, Ivo Caliò. A Discrete Macro Element Method for Modelling Ductile Steel Frames around the Openings of URM Buildings as Low Impact Retrofitting Strategy. Sustainability. 2021; 13 (17):9787.
Chicago/Turabian StyleGiuseppe Occhipinti; Francesco Cannizzaro; Salvatore Caddemi; Ivo Caliò. 2021. "A Discrete Macro Element Method for Modelling Ductile Steel Frames around the Openings of URM Buildings as Low Impact Retrofitting Strategy." Sustainability 13, no. 17: 9787.
The present paper proposes the use of stepped cross section devices on steel frames aiming at reproducing a pre-established target push-over curve. To this aim a Limited Resistance Plastic Device (LRPD) to be inserted along selected structural members is proposed. The following two main specific features for LRPD are required: any elastic flexural stiffness variation of the original selected member must be avoided; an ultimate plastic bending moment value equal to an assigned percentage of the original limit resistance value must be ensured. Steel frames equipped with LRPD are modeled by means of an extension of a recently proposed Fibre Smart Displacement Based (FSDB) beam element model, characterized by the adoption of updating shape functions. The novelty of this research, with respect to previous studies, regards: i) the formulation of a targeted plane steel frame by means of a new optimal design procedure for the LRPD with assigned stiffness and resistance features, independent of each other; ii) the development of a FSDB beam element approach suitably devoted to such a special application of discontinuous cross sections devices. The design procedure and the FSDB model for the analysis of the real behaviour of the proposed LRPD device in the field of distributed plasticity is validated against detailed 3D finite element models.
Salvatore Benfratello; Salvatore Caddemi; Luigi Palizzolo; Bartolomeo Pantò; Davide Rapicavoli; Santo Vazzano. Targeted steel frames by means of innovative moment resisting connections. Journal of Constructional Steel Research 2021, 183, 106695 .
AMA StyleSalvatore Benfratello, Salvatore Caddemi, Luigi Palizzolo, Bartolomeo Pantò, Davide Rapicavoli, Santo Vazzano. Targeted steel frames by means of innovative moment resisting connections. Journal of Constructional Steel Research. 2021; 183 ():106695.
Chicago/Turabian StyleSalvatore Benfratello; Salvatore Caddemi; Luigi Palizzolo; Bartolomeo Pantò; Davide Rapicavoli; Santo Vazzano. 2021. "Targeted steel frames by means of innovative moment resisting connections." Journal of Constructional Steel Research 183, no. : 106695.
Recent earthquakes have shown that the seismic behavior of noncode‐conforming reinforced concrete buildings are in several cases strongly affected by the nonlinear response and possible failure of the beam‐column joints. Beam‐column joint inelasticity is typically due to either shear cracking and failure of the central concrete panel or bond‐slip of the longitudinal steel bars. This paper proposes a new Joint with Hinges macro‐element capable of simulating the most important sources of nonlinearities in the joints. It consists of a quadrilateral central panel whose rigid edges are connected to the beams’ and columns’ end nodes through nonlinear finite‐length interfaces that represent the plastic hinge zones. The central panel deforms in shear only. The joint macro‐element accounts for the nonlinear shear response of the central panel, for the bond‐slip of the longitudinal rebars crossing the joint and for the nonlinear shear and flexural behavior of the plastic hinge zones of the beams and columns connected to the joint. The resulting model of the reinforced concrete frame is the assembly of nonlinear Joint with Hinges macro‐elements connected by elastic frame elements. The proposed formulation is applied in this paper to plane frames. Validation studies with results from available experimental tests on beam‐column joint subassemblages show the proposed model capability to predict the hysteretic responses and the failure mechanisms of connections with unreinforced joints and different beam reinforcement ratios.
Bartolomeo Pantò; Salvatore Caddemi; Ivo Caliò; Enrico Spacone. A 2D beam‐column joint macro‐element for the nonlinear analysis of RC frames. Earthquake Engineering & Structural Dynamics 2020, 50, 935 -954.
AMA StyleBartolomeo Pantò, Salvatore Caddemi, Ivo Caliò, Enrico Spacone. A 2D beam‐column joint macro‐element for the nonlinear analysis of RC frames. Earthquake Engineering & Structural Dynamics. 2020; 50 (3):935-954.
Chicago/Turabian StyleBartolomeo Pantò; Salvatore Caddemi; Ivo Caliò; Enrico Spacone. 2020. "A 2D beam‐column joint macro‐element for the nonlinear analysis of RC frames." Earthquake Engineering & Structural Dynamics 50, no. 3: 935-954.
Dynamic analyses and seismic assessments of multi-storey buildings at the urban level require large-scale simulations and computational procedures based on simplified but accurate numerical models. For this aim, the present paper proposes an equivalent non-uniform beam-like model, suitable for the dynamic analysis of buildings with an asymmetric plan and non-uniform vertical distribution of mass and stiffness. The equations of motion of this beam-like model, which presents only shear and torsional deformability, were derived through the application of Hamilton’s principle. The linear dynamic behaviour was evaluated by discretizing the continuous non-uniform model according to a Rayleigh–Ritz approach based on a suitable number of modal shapes of the uniform shear-torsional beam. In spite of its simplicity, the model is able to reproduce the dynamic behaviour of low- and mid-rise buildings with a significant reduction of the computational burden with respect to that required by more general models. The efficacy of the proposed approach was tested, by means of comparisons with linear Finite Element Model (FEM) simulations, on three multi-storey buildings characterized by different irregularities. The satisfactory agreement, in terms of natural frequencies, modes of vibration and seismic response, proves the capability of the proposed approach to reproduce the dynamic response of complex spatial multi-storey frames.
Annalisa Greco; Ilaria Fiore; Giuseppe Occhipinti; Salvatore Caddemi; Daniele Spina; Ivo Caliò. An Equivalent Non-Uniform Beam-Like Model for Dynamic Analysis of Multi-Storey Irregular Buildings. Applied Sciences 2020, 10, 3212 .
AMA StyleAnnalisa Greco, Ilaria Fiore, Giuseppe Occhipinti, Salvatore Caddemi, Daniele Spina, Ivo Caliò. An Equivalent Non-Uniform Beam-Like Model for Dynamic Analysis of Multi-Storey Irregular Buildings. Applied Sciences. 2020; 10 (9):3212.
Chicago/Turabian StyleAnnalisa Greco; Ilaria Fiore; Giuseppe Occhipinti; Salvatore Caddemi; Daniele Spina; Ivo Caliò. 2020. "An Equivalent Non-Uniform Beam-Like Model for Dynamic Analysis of Multi-Storey Irregular Buildings." Applied Sciences 10, no. 9: 3212.
Dynamic analyses and seismic assessments of multi-storey buildings at urban level require large-scale simulations and computational procedures based on simplified but accurate numerical models. At this aim the present paper propos-es an equivalent non-uniform beam-like model, suitable for the dynamic analysis of buildings with asymmetric plan and non-uniform vertical distribution of mass and stiffness. The equations of motion of this beam-like model, which pre-sents only shear and torsional deformability, are derived through the application of Hamilton’s principle. The linear dy-namic behaviour is evaluated by discretizing the continuous non-uniform model according to a Rayleigh-Ritz approach based on a suitable number of modal shapes of the uniform shear-torsional beam. In spite of its simplicity, the model is able to reproduce the dynamic behaviour of low- and mid-rise buildings with a significant reduction of the computa-tional burden with respect to that required by more general models. The efficacy of the proposed approach has been tested, by means of comparisons with linear FEM simulations, on three multi-storey buildings characterized by different irregularities. The satisfactory agreement, in terms of natural frequencies, modes of vibration and seismic response, proves the capability of the proposed approach to reproduce the dynamic response of complex spatial multi storey frames.
Annalisa Greco; Ilaria Fiore; Giuseppe Occhipinti; Salvatore Caddemi; Daniele Spina; Ivo Caliò. An Equivalent Non-uniform Beam-like Model for Dynamic Analysis of Multi-storey Irregular Buildings. 2020, 1 .
AMA StyleAnnalisa Greco, Ilaria Fiore, Giuseppe Occhipinti, Salvatore Caddemi, Daniele Spina, Ivo Caliò. An Equivalent Non-uniform Beam-like Model for Dynamic Analysis of Multi-storey Irregular Buildings. . 2020; ():1.
Chicago/Turabian StyleAnnalisa Greco; Ilaria Fiore; Giuseppe Occhipinti; Salvatore Caddemi; Daniele Spina; Ivo Caliò. 2020. "An Equivalent Non-uniform Beam-like Model for Dynamic Analysis of Multi-storey Irregular Buildings." , no. : 1.
Francesco Cannizzaro; J. De Los Rios; S. Caddemi; I. Caliò; S. Ilanko. On the use of a roving body with rotary inertia to locate cracks in beams. Journal of Sound and Vibration 2018, 425, 275 -300.
AMA StyleFrancesco Cannizzaro, J. De Los Rios, S. Caddemi, I. Caliò, S. Ilanko. On the use of a roving body with rotary inertia to locate cracks in beams. Journal of Sound and Vibration. 2018; 425 ():275-300.
Chicago/Turabian StyleFrancesco Cannizzaro; J. De Los Rios; S. Caddemi; I. Caliò; S. Ilanko. 2018. "On the use of a roving body with rotary inertia to locate cracks in beams." Journal of Sound and Vibration 425, no. : 275-300.
In this work, a model of the Euler–Bernoulli beam in presence of multiple‐concentrated open cracks, based on the adoption of a localized flexibility model, is adopted. The closed‐form solution in terms of transversal displacements due to static loads and general boundary condition is exploited to propose an inverse damage identification procedure. The proposed identification procedure does not require any solution algorithm, on the contrary is formulated by means of simple explicit sequential expressions for the crack positions and intensities including the identification of the integration constants. The number of possible detected cracks depends on the couples of adopted sensors. Undamaged beam zones can also be easily detected in relation to the sensor positions. The analytical character of the explicit expressions of the identification procedure makes the inverse formulation applicable to damaged beams included in more complex frame structures. The proposed procedure is applied for the identification of the number, position, and intensity of the cracks along simple straight beams and also to more complex frame structures with the aim of showing its simplicity for engineering applications. In addition, the robustness of the methodology here described is shown through an accurate analysis of the basic assumptions on which the theory relies and by means of a study of the effect of noise on the identification results.
S. Caddemi; I. Caliò; Francesco Cannizzaro; A. Morassi. A procedure for the identification of multiple cracks on beams and frames by static measurements. Structural Control and Health Monitoring 2018, 25, e2194 .
AMA StyleS. Caddemi, I. Caliò, Francesco Cannizzaro, A. Morassi. A procedure for the identification of multiple cracks on beams and frames by static measurements. Structural Control and Health Monitoring. 2018; 25 (8):e2194.
Chicago/Turabian StyleS. Caddemi; I. Caliò; Francesco Cannizzaro; A. Morassi. 2018. "A procedure for the identification of multiple cracks on beams and frames by static measurements." Structural Control and Health Monitoring 25, no. 8: e2194.
The experience of the recent earthquakes in Italy caused a shocking impact in terms of loss of human life and damage in buildings. In particular, when it comes to ancient constructions, their cultural and historical value overlaps with the economic and social one. Among the historical structures, churches have been the object of several studies which identified the main characteristics of the seismic response and the most probable collapse mechanisms. More rarely, academic studies have been devoted to ancient palaces, since they often exhibit irregular and complicated arrangement of the resisting elements, which makes their response very difficult to predict. In this paper, a palace located in L’Aquila, severely damaged by the seismic event of 2009 is the object of an accurate study. A historical reconstruction of the past strengthening interventions as well as a detailed geometric relief is performed to implement detailed numerical models of the structure. Both global and local models are considered and static nonlinear analyses are performed considering the influence of the input direction on the seismic vulnerability of the building. The damage pattern predicted by the numerical models is compared with that observed after the earthquake. The seismic vulnerability assessments are performed in terms of ultimate peak ground acceleration (PGA) using capacity curves and the Italian code spectrum. The results are compared in terms of ultimate ductility demand evaluated performing nonlinear dynamic analyses considering the actual registered seismic input of L’Aquila earthquake.
Francesco Cannizzaro; Bartolomeo Pantò; Marco Lepidi; Salvatore Caddemi; Ivo Caliò. Multi-Directional Seismic Assessment of Historical Masonry Buildings by Means of Macro-Element Modelling: Application to a Building Damaged during the L’Aquila Earthquake (Italy). Buildings 2017, 7, 106 .
AMA StyleFrancesco Cannizzaro, Bartolomeo Pantò, Marco Lepidi, Salvatore Caddemi, Ivo Caliò. Multi-Directional Seismic Assessment of Historical Masonry Buildings by Means of Macro-Element Modelling: Application to a Building Damaged during the L’Aquila Earthquake (Italy). Buildings. 2017; 7 (4):106.
Chicago/Turabian StyleFrancesco Cannizzaro; Bartolomeo Pantò; Marco Lepidi; Salvatore Caddemi; Ivo Caliò. 2017. "Multi-Directional Seismic Assessment of Historical Masonry Buildings by Means of Macro-Element Modelling: Application to a Building Damaged during the L’Aquila Earthquake (Italy)." Buildings 7, no. 4: 106.
A reliable numerical evaluation of the nonlinear behaviour of historical masonry structures, before and after a seismic retrofitting, is a fundamental issue in the design of the structural retrofitting. Many strengthening techniques have been introduced aimed at improving the structural performance of existing structures that, if properly designed and applied, provide an effective contribution to the preservation of their cultural value. Among these strategies, the use of fabric-reinforced polymeric (FRP) materials on masonry surface is being widely adopted for practical engineering purposes. The application of strips or 2D grid composite layers is a low invasive and easy to apply retrofitting strategy, that is able to improve both the in-plane and the out of plane behaviour of masonry elements also in the presence of complex geometries thanks to their flexibility. For this reason, these techniques are frequently employed for reinforcing masonry curved elements, such as arches and vaults. In this paper, taking advantage of an existing general framework based on a discrete element approach previously introduced by the authors, a discrete element conceived for modelling the interaction between masonry and FRP reinforcement is applied to different curved masonry vaults typologies. This model, already used for evaluating the nonlinear behaviour of masonry arches, is here employed for the first time to evaluate the effectiveness of FRP reinforcements on double curvature elements. After a theoretical description of the proposed strategy, two applications relative to an arch and a dome, subjected to seismic loads, with different reinforced conditions, are presented. The benefit provided by the application of FRP strips is also compared with that associated to traditional retrofitting techniques. A sensitivity study is performed with respect to the structure scale factor.
Bartolomeo Pantò; Francesco Cannizzaro; Salvatore Caddemi; Ivo Caliò; César Chácara; Paulo B. Lourenço. Nonlinear Modelling of Curved Masonry Structures after Seismic Retrofit through FRP Reinforcing. Buildings 2017, 7, 79 .
AMA StyleBartolomeo Pantò, Francesco Cannizzaro, Salvatore Caddemi, Ivo Caliò, César Chácara, Paulo B. Lourenço. Nonlinear Modelling of Curved Masonry Structures after Seismic Retrofit through FRP Reinforcing. Buildings. 2017; 7 (4):79.
Chicago/Turabian StyleBartolomeo Pantò; Francesco Cannizzaro; Salvatore Caddemi; Ivo Caliò; César Chácara; Paulo B. Lourenço. 2017. "Nonlinear Modelling of Curved Masonry Structures after Seismic Retrofit through FRP Reinforcing." Buildings 7, no. 4: 79.
F. Cannizzaro; A. Greco; S. Caddemi; I. Caliò. Closed form solutions of a multi-cracked circular arch under static loads. International Journal of Solids and Structures 2017, 121, 191 -200.
AMA StyleF. Cannizzaro, A. Greco, S. Caddemi, I. Caliò. Closed form solutions of a multi-cracked circular arch under static loads. International Journal of Solids and Structures. 2017; 121 ():191-200.
Chicago/Turabian StyleF. Cannizzaro; A. Greco; S. Caddemi; I. Caliò. 2017. "Closed form solutions of a multi-cracked circular arch under static loads." International Journal of Solids and Structures 121, no. : 191-200.
Bartolomeo Pantò; D. Rapicavoli; S. Caddemi; I. Caliò. A smart displacement based (SDB) beam element with distributed plasticity. Applied Mathematical Modelling 2017, 44, 336 -356.
AMA StyleBartolomeo Pantò, D. Rapicavoli, S. Caddemi, I. Caliò. A smart displacement based (SDB) beam element with distributed plasticity. Applied Mathematical Modelling. 2017; 44 ():336-356.
Chicago/Turabian StyleBartolomeo Pantò; D. Rapicavoli; S. Caddemi; I. Caliò. 2017. "A smart displacement based (SDB) beam element with distributed plasticity." Applied Mathematical Modelling 44, no. : 336-356.
S. Caddemi; I. Caliò; Francesco Cannizzaro. On the dynamic stability of shear deformable beams under a tensile load. Journal of Sound and Vibration 2016, 373, 89 -103.
AMA StyleS. Caddemi, I. Caliò, Francesco Cannizzaro. On the dynamic stability of shear deformable beams under a tensile load. Journal of Sound and Vibration. 2016; 373 ():89-103.
Chicago/Turabian StyleS. Caddemi; I. Caliò; Francesco Cannizzaro. 2016. "On the dynamic stability of shear deformable beams under a tensile load." Journal of Sound and Vibration 373, no. : 89-103.
Recent earthquakes have demonstrated the high vulnerability of cultural heritage buildings, whose seismic assessment and rehabilitation constitute an important issue in seismic regions around the world. The high nonlinear behaviour of masonry material requires ad hoc refined finite element numerical models, whose complexity and computational cost are generally unsuitable for practical applications. For these reasons many authors proposed simplified numerical strategies to be used in engineering practice. However, most of these alternative methods are oversimplified since based on the assumption of in plane behaviour of masonry walls. In this paper a discrete-modelling approach for the simulation of both the in plane and out of-plane response of masonry structures is proposed. The method is applied to a basilica plan church, which has been partially investigated in the literature. The results show the capability of the proposed discrete element approach to simulate the nonlinear response of monumental structures also in those cases in which the ‘in’ and the ‘out’ of plane response cannot be decoupled, as it happens for many structural layouts typical of churches, ancient palaces and several other monumental structures.
Bartolomeo Pantò; Francesco Cannizzaro; S. Caddemi; I. Caliò. 3D macro-element modelling approach for seismic assessment of historical masonry churches. Advances in Engineering Software 2016, 97, 40 -59.
AMA StyleBartolomeo Pantò, Francesco Cannizzaro, S. Caddemi, I. Caliò. 3D macro-element modelling approach for seismic assessment of historical masonry churches. Advances in Engineering Software. 2016; 97 ():40-59.
Chicago/Turabian StyleBartolomeo Pantò; Francesco Cannizzaro; S. Caddemi; I. Caliò. 2016. "3D macro-element modelling approach for seismic assessment of historical masonry churches." Advances in Engineering Software 97, no. : 40-59.
Tensile instability in beam-like structures has been highlighted in very few papers; the studies reported in the specific literature are limited to beam-columns characterised either by high shear deformation or by the presence of a single structural junction allowing a transversal displacement discontinuity. Moreover, to the authors’ knowledge, the flutter instability associated to tensile axial load has not yet been disclosed. This work aims to offer further contribution to the knowledge of tensile instability of beam-columns by considering the dynamic instability of an Euler Bernoulli beam in presence of an arbitrary number of internal sliders endowed with translational elastic springs. The use of the generalised functions allows an exact evaluation of the eigensolution, provided in closed form, both for conservative and nonconservative axial load. In particular, the following relevant question is posed: Can a beam-column undergo tensile flutter instability? A comprehensive parametric analysis conducted in this work gives an affirmative answer to the asked question.
S Caddemi; I Caliò; Francesco Cannizzaro. Advances in dynamic instability: can a beam-column undergo tensile flutter? Journal of Vibration and Control 2015, 23, 1309 -1320.
AMA StyleS Caddemi, I Caliò, Francesco Cannizzaro. Advances in dynamic instability: can a beam-column undergo tensile flutter? Journal of Vibration and Control. 2015; 23 (8):1309-1320.
Chicago/Turabian StyleS Caddemi; I Caliò; Francesco Cannizzaro. 2015. "Advances in dynamic instability: can a beam-column undergo tensile flutter?" Journal of Vibration and Control 23, no. 8: 1309-1320.
S. Caddemi; Ivo Caliò; Francesco Cannizzaro. Influence of an elastic end support on the dynamic stability of Beck׳s column with multiple weak sections. International Journal of Non-Linear Mechanics 2015, 69, 14 -28.
AMA StyleS. Caddemi, Ivo Caliò, Francesco Cannizzaro. Influence of an elastic end support on the dynamic stability of Beck׳s column with multiple weak sections. International Journal of Non-Linear Mechanics. 2015; 69 ():14-28.
Chicago/Turabian StyleS. Caddemi; Ivo Caliò; Francesco Cannizzaro. 2015. "Influence of an elastic end support on the dynamic stability of Beck׳s column with multiple weak sections." International Journal of Non-Linear Mechanics 69, no. : 14-28.
S. Caddemi; I. Caliò; F. Cannizzaro; B. Pantò. The Seismic Assessment of Historical Masonry Structures. Proceedings of the Twelfth International Conference on Computational Structures Technology 2014, 1 .
AMA StyleS. Caddemi, I. Caliò, F. Cannizzaro, B. Pantò. The Seismic Assessment of Historical Masonry Structures. Proceedings of the Twelfth International Conference on Computational Structures Technology. 2014; ():1.
Chicago/Turabian StyleS. Caddemi; I. Caliò; F. Cannizzaro; B. Pantò. 2014. "The Seismic Assessment of Historical Masonry Structures." Proceedings of the Twelfth International Conference on Computational Structures Technology , no. : 1.
Shear deformations in beam-like structures as well as devices allowing deflection discontinuities, besides influencing the compressive buckling, can induce instability in presence of tensile axial loads. In this work a novel study to address both the compressive and the tensile buckling in slender beams in presence of multiple internal sliders endowed with translational springs, that induce deflection discontinuities along the beam axis, is presented. The general exact closed-form solutions is derived as a function of four boundary conditions only, as in the case of homogeneous beam, irrespective on the number of concentrated singularities. The range where the tensile buckling load values are comparable to the compressive counterpart is highlighted. Furthermore, sudden switches from symmetric to anti-symmetric buckling shapes are identified. Finally, for an increasing number of deflection discontinuities an interesting comparison with a uniform column with distributed shear deformations, according to the Timoshenko model, is presented. The latter comparison suggests that elastic internal sliders, which allow transversal deflection discontinuities, can be interpreted as concentrated shear deformations and are addressed to as shear deformation singularities.
S. Caddemi; Ivo Caliò; Francesco Cannizzaro. Tensile and compressive buckling of columns with shear deformation singularities. Meccanica 2014, 50, 707 -720.
AMA StyleS. Caddemi, Ivo Caliò, Francesco Cannizzaro. Tensile and compressive buckling of columns with shear deformation singularities. Meccanica. 2014; 50 (3):707-720.
Chicago/Turabian StyleS. Caddemi; Ivo Caliò; Francesco Cannizzaro. 2014. "Tensile and compressive buckling of columns with shear deformation singularities." Meccanica 50, no. 3: 707-720.
In this paper, an exact procedure for the reconstruction of multiple concentrated damages on a straight beam is proposed. The concentrated damages are modelled as Dirac’s delta distributions capturing the effect of concentrated stiffness reduction. The presented procedure requires the knowledge of vibration mode shape displacements together with the relevant natural frequency, for the reconstruction of each damage position and intensity. The exact solution of the inverse problem at hand has been pursued by exploiting the analytical structure of the explicit closed form expressions provided for the vibration mode shapes of beams in the presence of an arbitrary number of cracks. The proposed procedure is first presented under the hypothesis that the displacements of a vibration mode shape are known at the cracked cross-sections. In this case, explicit closed form expressions of the crack severities are formulated. A further simple reconstruction approach allows the evaluation of the exact positions and intensity of the concentrated damages, if displacements of two vibration mode shapes are known at a single cross-section between two consecutive cracks. The proposed reconstruction procedure is applied for the identification of multiple cracks on a free–free beam where measurements have been simulated by means of a finite element analysis.
S. Caddemi; Ivo Caliò. Exact reconstruction of multiple concentrated damages on beams. Acta Mechanica 2014, 225, 3137 -3156.
AMA StyleS. Caddemi, Ivo Caliò. Exact reconstruction of multiple concentrated damages on beams. Acta Mechanica. 2014; 225 (11):3137-3156.
Chicago/Turabian StyleS. Caddemi; Ivo Caliò. 2014. "Exact reconstruction of multiple concentrated damages on beams." Acta Mechanica 225, no. 11: 3137-3156.
S. Caddemi; Ivo Caliò; Francesco Cannizzaro. Flutter and divergence instability of the multi-cracked cantilever beam-column. Journal of Sound and Vibration 2014, 333, 1718 -1733.
AMA StyleS. Caddemi, Ivo Caliò, Francesco Cannizzaro. Flutter and divergence instability of the multi-cracked cantilever beam-column. Journal of Sound and Vibration. 2014; 333 (6):1718-1733.
Chicago/Turabian StyleS. Caddemi; Ivo Caliò; Francesco Cannizzaro. 2014. "Flutter and divergence instability of the multi-cracked cantilever beam-column." Journal of Sound and Vibration 333, no. 6: 1718-1733.
S. Caddemi; Ivo Caliò; Francesco Cannizzaro. The influence of multiple cracks on tensile and compressive buckling of shear deformable beams. International Journal of Solids and Structures 2013, 50, 3166 -3183.
AMA StyleS. Caddemi, Ivo Caliò, Francesco Cannizzaro. The influence of multiple cracks on tensile and compressive buckling of shear deformable beams. International Journal of Solids and Structures. 2013; 50 (20):3166-3183.
Chicago/Turabian StyleS. Caddemi; Ivo Caliò; Francesco Cannizzaro. 2013. "The influence of multiple cracks on tensile and compressive buckling of shear deformable beams." International Journal of Solids and Structures 50, no. 20: 3166-3183.