Sergio Lagomarsino | University of Genova (original) (raw)

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Papers by Sergio Lagomarsino

Research paper thumbnail of Proposta di spettri di piano per la verifica di elementi non strutturali e meccanismi locali negli edifici in muratura

Research paper thumbnail of Comparison of Fragility Sets to Assess the Effectiveness of Retrofit Interventions on Masonry Buildings in Italy

Buildings

Seismic events that have occurred in Italy in recent decades have shown the significant vulnerabi... more Seismic events that have occurred in Italy in recent decades have shown the significant vulnerability of the Italian building stock. In particular, residential masonry buildings have suffered serious damage, highlighting the need to plan effective mitigation strategies as soon as possible. In this context, this study aims to evaluate the effectiveness of possible retrofit interventions for masonry buildings. Fragility curves of macro-classes of residential masonry buildings have been developed in both as-built and retrofitted conditions within the DPC-ReLUIS agreement (Department of Civil Protection—Network of University Laboratories for Earthquake Engineering). In particular, three sets of fragility curves, developed by the University of Padova (UniPD) and the University of Genova (UniGEa and UniGEb) are discussed and compared herein. The three models show similar estimates of the expected structural improvements for the examined retrofit interventions when applied to the building ...

Research paper thumbnail of Analisi di alcune pareti in un edificio storico

Research paper thumbnail of Damage Detection of Masonry Structures Under Shaking Table Tests Through Relative Displacements by 3D Optical Markers

Research paper thumbnail of Structural framework evolution from the 17th to 20th century in the Genoa Republic's Shipyard. Architectural archeology investigates the layers of structure

Research paper thumbnail of Seismic analysis of a masonry cross vault through shaking table tests: The case study of the Dey Mosque in Algiers

Earthquakes and Structures, 2020

This paper presents the results of a monodirectional shaking table test on a full-scale unreinfor... more This paper presents the results of a monodirectional shaking table test on a full-scale unreinforced masonry cross vault characterized by asymmetric boundary conditions. The specimen represents a vault of the mosque of Dey in Algiers (Algeria), reproducing in detail the mechanical characteristics of masonry, and the constructive details including the presence of some peculiar wooden logs placed within the vault\'s configurations were studied by using an incremental dynamic analysis up to the collapse of the vault without the steel bars. The use of an innovative high-resolution 3D optical system allowed measure displacement data of the cross vault during the shake table tests. The experimental results were analysed in terms of evolution of damage mechanisms, and in-plane and out-of-plane deformations. Moreover, the dynamic properties of the structure were investigated by means of an experimental modal analysis.

Research paper thumbnail of Experimental testing of the seismic in-plane displacement capacity of masonry cross vaults through a scale model

Bulletin of Earthquake Engineering, Sep 16, 2015

Since cross masonry vaults represent one of the more widespread types of horizontal structural el... more Since cross masonry vaults represent one of the more widespread types of horizontal structural elements in historical constructions, understanding their behaviour is a crucial precondition for the accurate assessment of the global response of buildings to earthquakes. In spite of the importance of this topic, the complexity of evaluation three-dimensional response of vaults still represents a challenge for researchers. Experimental investigations can be a valid tool to analyse this difficult problem, as they provide useful results that can validate the reliability of the numerical and analytical tools developed for analysis. In this paper, the results of an experimental campaign on 1:5 scale model of a masonry cross vault are presented. The main aim was to evaluate the response of the vaults in the context of a global analysis of historic masonry buildings by determining their ultimate in-plane seismic capacity (diaphragm effect) in terms of stiffness, strength, and ultimate displacements. Their three-dimensional damage mechanisms on the vaults was also described. The model, made of 3D printed plastic blocks with dry joints, was tested by statically applying different horizontal displacements settings to the abutments in order to simulate differential displacements of the supports (walls or pillars). In particular, in-plane horizontal shear distortions and longitudinal opening/closing of the abutments, as they are the most common seismic damage mechanisms seen in masonry vault buildings, were applied.

Research paper thumbnail of Tilting plane tests on a small-scale masonry cross vault: Experimental results and numerical simulations through a heterogeneous approach

Engineering Structures, Sep 1, 2016

Research paper thumbnail of Damage in brick shear masonry walls

Research paper thumbnail of Operational critical issues filling in the Italian form for the post-earthquake damage assessment of churches (A-DC 2006)

Procedia Structural Integrity

Research paper thumbnail of Modelling and Seismic Response Analysis of Existing Italian Residential RC Buildings Retrofitted by Seismic Isolation

Journal of Earthquake Engineering, 2022

Research paper thumbnail of Vulnerability analysis of unreinforced masonry churches (EQC 14/660) – Final Report

Research paper thumbnail of 2.4 Gli edifici in muratura nei centri storici dell’Aquilano

Research paper thumbnail of Theoretically-based and practice-oriented formulations for the floor spectra evaluation

Earthquakes and Structures, 2018

This paper proposes a new analytical formulation for computing the seismic input at various level... more This paper proposes a new analytical formulation for computing the seismic input at various levels of a structure in terms of floor response spectra. The approach, which neglects the dynamic interaction between primary structure and secondary element, is particularly useful for the seismic assessment of secondary and non-structural elements. The proposed formulation has a robust theoretical basis and it is based on few meaningful dynamic parameters of the main building. The method has been validated in the linear and nonlinear behavior of the main building through results coming from both experimental tests (available in literature) and parametric numerical analyses. The conditions, for which the Floor Spectrum Approach and its simplified assumptions are valid, have been derived in terms of specific interval ratios between the mass of the secondary element and the participant mass of the main structure. Finally, a practice-oriented formulation has been derived, which could be easily...

Research paper thumbnail of The “Gothic House” in Arquata Scrivia (Italy): Constructive Details and Seismic Assessment of a Timber Framed Masonry Structure

Lecture Notes in Civil Engineering, 2016

The paper presents the analysis of the structural and constructive system together with that of t... more The paper presents the analysis of the structural and constructive system together with that of the seismic response of the “Gothic house” in ArquataScrivia, that constitutes a rare example of timber framed masonry structure in Piedmont (Italy). Besides a certain diffusion around Europe, which is documented in the 19th century chronicles, in Italy there are only a few timber-framed buildings left. The timber frame system of the “Gothic house” presents some analogies with the French and German one (area in which it is more widespread than Italy) although it is characterized exclusively by the presence of horizontal and vertical timber elements. In the paper, the analysis of the building has been supported by an extensive investigation campaign that included the execution of several non-destructive tests on both masonry and timber elements. Preliminary step for setting-up the investigation plan was a sensitivity analysis carried out on an equivalent frame model of the building by performing nonlinear static analyses. Aims of such sensitivity analysis were, firstly, to address the as-built information phase and, then, to improve the reliability of the final model to be adopted for the seismic assessment.

Research paper thumbnail of Il contributo di ReLUIS nelle attività di supporto all’emergenza sismica del centro Italia 2016

The improvement of seismic performances and the enhancement of the energy efficiency of existing ... more The improvement of seismic performances and the enhancement of the energy efficiency of existing buildings have nowadays become a priority. Indeed, much of the existing building stock is characterized by great structural, architectural and thermal obsolescence. In addition to the renovation of existing buildings, a very important aspect is the repair and upgrading of buildings recently damaged by the seismic events that hit the Italian territory. In particular, this article takes into account a school located in the municipality of Pievebovigliana, province of Macerata, which got damaged by the earthquakes that hit Central Italy on 24.08.2016 and 30.10.2016. In detail, the article refers to a one-story building characterized by an irregular plan configuration. The gravity load resisting system is made by masonry walls with regular blocks; in addition, few reinforced concrete columns embedded in the masonry walls support the roof girders. Different strategies of anti-seismic retrofit...

Research paper thumbnail of Seismic Assessment and Strengthening Interventions of Atop Single-Block Rocking Elements in Monumental Buildings: the Case Study of the San Felice sul Panaro Fortress

12th International Conference on Structural Analysis of Historical Constructions, 2021

Research paper thumbnail of A Numerical Analysis on the Shape of the Response Spectra in Cohesive and Granular Soils with Non-Linear Behaviour. Proceedings of the Sixth International Conference on Numerical Methods in Geomechanics, 11-15 April 1988, Innsbruck, Austria. Volumes 1 - 3

The problem of the local amplification of surface deposits in earthquake engineering is fully dea... more The problem of the local amplification of surface deposits in earthquake engineering is fully dealt with and much importance is given to the non-linear behaviour of the ground. A numerical analysis, carried out on homogeneous sites of sand or clay of different thicknesses and mechanical characteristics, has evaluated the influence of these parameters on the free field response of the ground. The magnitudes taken into account are: the peak acceleration of the time history on the surface of soil, and the response spectrum at the same point. These are the ones most used at the design level. In particular this paper sets out to give useful indications for the definition of the response spectra in studies of seismic microzonation. (TRRL)

Research paper thumbnail of Static and Dynamic Testing on a Brick Masonry Pavilion Vault of the San Francesco di Paola Convent, in Roccabernarda (KR), Italy

RILEM Bookseries, 2019

The work describes the static and dynamic experimentation carried out on a pavilion vault, recons... more The work describes the static and dynamic experimentation carried out on a pavilion vault, reconstructed in brick masonry with traditional techniques in an old partially collapsed convent. The vault was instrumented by using special bricks in some points, equipped with strain gauges inside them, in order to measure the stress state under static and dynamic conditions. The static tests were carried out through vertical loads at the extrados, uniformly distributed over the entire plan or, asymmetrically, only on a quarter of the vault plan. The dynamic tests were carried out by inducing the vibration to the entire convent through explosive charges, placed at a short distance and calibrated in such a way as to induce an excitation that is as similar as possible to an impulsive earthquake motion of low intensity. The results have shown the good behavior of this structural element under dynamic conditions, even if the level of excitation was rather low. Moreover, a first calibration of t...

Research paper thumbnail of Rintc Project: Nonlinear Dynamic Analyses of Italian Code-Conforming Reinforced Concrete Buildings for Risk of Collapse Assessment

Proceedings of the 6th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2015), 2017

Research paper thumbnail of Proposta di spettri di piano per la verifica di elementi non strutturali e meccanismi locali negli edifici in muratura

Research paper thumbnail of Comparison of Fragility Sets to Assess the Effectiveness of Retrofit Interventions on Masonry Buildings in Italy

Buildings

Seismic events that have occurred in Italy in recent decades have shown the significant vulnerabi... more Seismic events that have occurred in Italy in recent decades have shown the significant vulnerability of the Italian building stock. In particular, residential masonry buildings have suffered serious damage, highlighting the need to plan effective mitigation strategies as soon as possible. In this context, this study aims to evaluate the effectiveness of possible retrofit interventions for masonry buildings. Fragility curves of macro-classes of residential masonry buildings have been developed in both as-built and retrofitted conditions within the DPC-ReLUIS agreement (Department of Civil Protection—Network of University Laboratories for Earthquake Engineering). In particular, three sets of fragility curves, developed by the University of Padova (UniPD) and the University of Genova (UniGEa and UniGEb) are discussed and compared herein. The three models show similar estimates of the expected structural improvements for the examined retrofit interventions when applied to the building ...

Research paper thumbnail of Analisi di alcune pareti in un edificio storico

Research paper thumbnail of Damage Detection of Masonry Structures Under Shaking Table Tests Through Relative Displacements by 3D Optical Markers

Research paper thumbnail of Structural framework evolution from the 17th to 20th century in the Genoa Republic's Shipyard. Architectural archeology investigates the layers of structure

Research paper thumbnail of Seismic analysis of a masonry cross vault through shaking table tests: The case study of the Dey Mosque in Algiers

Earthquakes and Structures, 2020

This paper presents the results of a monodirectional shaking table test on a full-scale unreinfor... more This paper presents the results of a monodirectional shaking table test on a full-scale unreinforced masonry cross vault characterized by asymmetric boundary conditions. The specimen represents a vault of the mosque of Dey in Algiers (Algeria), reproducing in detail the mechanical characteristics of masonry, and the constructive details including the presence of some peculiar wooden logs placed within the vault\'s configurations were studied by using an incremental dynamic analysis up to the collapse of the vault without the steel bars. The use of an innovative high-resolution 3D optical system allowed measure displacement data of the cross vault during the shake table tests. The experimental results were analysed in terms of evolution of damage mechanisms, and in-plane and out-of-plane deformations. Moreover, the dynamic properties of the structure were investigated by means of an experimental modal analysis.

Research paper thumbnail of Experimental testing of the seismic in-plane displacement capacity of masonry cross vaults through a scale model

Bulletin of Earthquake Engineering, Sep 16, 2015

Since cross masonry vaults represent one of the more widespread types of horizontal structural el... more Since cross masonry vaults represent one of the more widespread types of horizontal structural elements in historical constructions, understanding their behaviour is a crucial precondition for the accurate assessment of the global response of buildings to earthquakes. In spite of the importance of this topic, the complexity of evaluation three-dimensional response of vaults still represents a challenge for researchers. Experimental investigations can be a valid tool to analyse this difficult problem, as they provide useful results that can validate the reliability of the numerical and analytical tools developed for analysis. In this paper, the results of an experimental campaign on 1:5 scale model of a masonry cross vault are presented. The main aim was to evaluate the response of the vaults in the context of a global analysis of historic masonry buildings by determining their ultimate in-plane seismic capacity (diaphragm effect) in terms of stiffness, strength, and ultimate displacements. Their three-dimensional damage mechanisms on the vaults was also described. The model, made of 3D printed plastic blocks with dry joints, was tested by statically applying different horizontal displacements settings to the abutments in order to simulate differential displacements of the supports (walls or pillars). In particular, in-plane horizontal shear distortions and longitudinal opening/closing of the abutments, as they are the most common seismic damage mechanisms seen in masonry vault buildings, were applied.

Research paper thumbnail of Tilting plane tests on a small-scale masonry cross vault: Experimental results and numerical simulations through a heterogeneous approach

Engineering Structures, Sep 1, 2016

Research paper thumbnail of Damage in brick shear masonry walls

Research paper thumbnail of Operational critical issues filling in the Italian form for the post-earthquake damage assessment of churches (A-DC 2006)

Procedia Structural Integrity

Research paper thumbnail of Modelling and Seismic Response Analysis of Existing Italian Residential RC Buildings Retrofitted by Seismic Isolation

Journal of Earthquake Engineering, 2022

Research paper thumbnail of Vulnerability analysis of unreinforced masonry churches (EQC 14/660) – Final Report

Research paper thumbnail of 2.4 Gli edifici in muratura nei centri storici dell’Aquilano

Research paper thumbnail of Theoretically-based and practice-oriented formulations for the floor spectra evaluation

Earthquakes and Structures, 2018

This paper proposes a new analytical formulation for computing the seismic input at various level... more This paper proposes a new analytical formulation for computing the seismic input at various levels of a structure in terms of floor response spectra. The approach, which neglects the dynamic interaction between primary structure and secondary element, is particularly useful for the seismic assessment of secondary and non-structural elements. The proposed formulation has a robust theoretical basis and it is based on few meaningful dynamic parameters of the main building. The method has been validated in the linear and nonlinear behavior of the main building through results coming from both experimental tests (available in literature) and parametric numerical analyses. The conditions, for which the Floor Spectrum Approach and its simplified assumptions are valid, have been derived in terms of specific interval ratios between the mass of the secondary element and the participant mass of the main structure. Finally, a practice-oriented formulation has been derived, which could be easily...

Research paper thumbnail of The “Gothic House” in Arquata Scrivia (Italy): Constructive Details and Seismic Assessment of a Timber Framed Masonry Structure

Lecture Notes in Civil Engineering, 2016

The paper presents the analysis of the structural and constructive system together with that of t... more The paper presents the analysis of the structural and constructive system together with that of the seismic response of the “Gothic house” in ArquataScrivia, that constitutes a rare example of timber framed masonry structure in Piedmont (Italy). Besides a certain diffusion around Europe, which is documented in the 19th century chronicles, in Italy there are only a few timber-framed buildings left. The timber frame system of the “Gothic house” presents some analogies with the French and German one (area in which it is more widespread than Italy) although it is characterized exclusively by the presence of horizontal and vertical timber elements. In the paper, the analysis of the building has been supported by an extensive investigation campaign that included the execution of several non-destructive tests on both masonry and timber elements. Preliminary step for setting-up the investigation plan was a sensitivity analysis carried out on an equivalent frame model of the building by performing nonlinear static analyses. Aims of such sensitivity analysis were, firstly, to address the as-built information phase and, then, to improve the reliability of the final model to be adopted for the seismic assessment.

Research paper thumbnail of Il contributo di ReLUIS nelle attività di supporto all’emergenza sismica del centro Italia 2016

The improvement of seismic performances and the enhancement of the energy efficiency of existing ... more The improvement of seismic performances and the enhancement of the energy efficiency of existing buildings have nowadays become a priority. Indeed, much of the existing building stock is characterized by great structural, architectural and thermal obsolescence. In addition to the renovation of existing buildings, a very important aspect is the repair and upgrading of buildings recently damaged by the seismic events that hit the Italian territory. In particular, this article takes into account a school located in the municipality of Pievebovigliana, province of Macerata, which got damaged by the earthquakes that hit Central Italy on 24.08.2016 and 30.10.2016. In detail, the article refers to a one-story building characterized by an irregular plan configuration. The gravity load resisting system is made by masonry walls with regular blocks; in addition, few reinforced concrete columns embedded in the masonry walls support the roof girders. Different strategies of anti-seismic retrofit...

Research paper thumbnail of Seismic Assessment and Strengthening Interventions of Atop Single-Block Rocking Elements in Monumental Buildings: the Case Study of the San Felice sul Panaro Fortress

12th International Conference on Structural Analysis of Historical Constructions, 2021

Research paper thumbnail of A Numerical Analysis on the Shape of the Response Spectra in Cohesive and Granular Soils with Non-Linear Behaviour. Proceedings of the Sixth International Conference on Numerical Methods in Geomechanics, 11-15 April 1988, Innsbruck, Austria. Volumes 1 - 3

The problem of the local amplification of surface deposits in earthquake engineering is fully dea... more The problem of the local amplification of surface deposits in earthquake engineering is fully dealt with and much importance is given to the non-linear behaviour of the ground. A numerical analysis, carried out on homogeneous sites of sand or clay of different thicknesses and mechanical characteristics, has evaluated the influence of these parameters on the free field response of the ground. The magnitudes taken into account are: the peak acceleration of the time history on the surface of soil, and the response spectrum at the same point. These are the ones most used at the design level. In particular this paper sets out to give useful indications for the definition of the response spectra in studies of seismic microzonation. (TRRL)

Research paper thumbnail of Static and Dynamic Testing on a Brick Masonry Pavilion Vault of the San Francesco di Paola Convent, in Roccabernarda (KR), Italy

RILEM Bookseries, 2019

The work describes the static and dynamic experimentation carried out on a pavilion vault, recons... more The work describes the static and dynamic experimentation carried out on a pavilion vault, reconstructed in brick masonry with traditional techniques in an old partially collapsed convent. The vault was instrumented by using special bricks in some points, equipped with strain gauges inside them, in order to measure the stress state under static and dynamic conditions. The static tests were carried out through vertical loads at the extrados, uniformly distributed over the entire plan or, asymmetrically, only on a quarter of the vault plan. The dynamic tests were carried out by inducing the vibration to the entire convent through explosive charges, placed at a short distance and calibrated in such a way as to induce an excitation that is as similar as possible to an impulsive earthquake motion of low intensity. The results have shown the good behavior of this structural element under dynamic conditions, even if the level of excitation was rather low. Moreover, a first calibration of t...

Research paper thumbnail of Rintc Project: Nonlinear Dynamic Analyses of Italian Code-Conforming Reinforced Concrete Buildings for Risk of Collapse Assessment

Proceedings of the 6th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2015), 2017