Proceedings of the 7th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2015)
Structural monitoring in highly seismic areas represents a valuable source of information in both... more Structural monitoring in highly seismic areas represents a valuable source of information in both structures' behaviour understanding and identification techniques' validation. In this paper the case of a permanent monitoring system, installed in a thirteenth century monumental site, the Santa Maria of Collemaggio Basilica (Italy), is presented. Both low intensity tremors and strong motion earthquakes are recorded. Recent earthquakes provided both input (base ground accelerogram) and output (structure's response) signals. Hence a comparison has been drawn between the results from a set of Output-Only (OO) Identification techniques and a set of Input-Output (IO) algorithms. In the group of IO techniques, a rapid and easily implementable technique, based on an OLS linear regression model, is presented. Different results between the IO techniques, driven by earthquake recordings, and the OO ones, driven by ambient vibration data, emerge. Attempts are made to capture the system's dynamics, by means of a linear regression model, stressing possible research issues in the identification of non stationary systems subjected to seismic excitation. 1770 COMPDYN 2019 7 th ECCOMAS Thematic Conference on Computational Methods in Structural Dynamics and Earthquake Engineering M. Papadrakakis, M. Fragiadakis (eds.
Masonry towers, located in seismic zones, are vulnerable and prone to damages up to compromise th... more Masonry towers, located in seismic zones, are vulnerable and prone to damages up to compromise their stability. The scatter of data on the mechanical properties of masonry, geometry and boundary conditions determine a lack of building knowledge on their expected behaviour. Therefore the assessment of the seismic capacity represents a critical task. This paper contributes to the issue of seismic analysis of masonry towers, focusing a meaningful case study: the St.Silvestro belfry in L’Aquila, Italy. The tower, severely damaged by the 2009 earthquake sequence, underwent extensive restoration works, endeavoured to mitigate its vulnerability. The observed seismic damage, the performed no-destructive testing campaign and the accomplished rehabilitation measures are described in the paper. The authors appraised the actual seismic performances of the St.Silvestro belfry, reinforced by the last restoration works. At first, the Operational Modal Analysis (OMA) is carried out to enhance build...
8th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering Methods in Structural Dynamics and Earthquake Engineering
In the last decades, the applications of structural monitoring are moving toward the field of civ... more In the last decades, the applications of structural monitoring are moving toward the field of civil engineering and infrastructures. Nevertheless, if the structures have damages, it does not mean that they have a complete loss of functionality, but rather that the system is no longer in an optimal condition so that, if the damage increases, the structure can collapse. Structural Health Monitoring (SHM), a process for the identification of damage, periodically collects data from suitable sensors that allow to characterize the damage and establishes the health status of the structure. Therefore, this monitoring will provide information on the structure condition, mostly about its integrity, in a short time, and, for infrastructures and civil structures, it is necessary to assess performance and health status. The aim of this work is to design an Internet of Things (IoT) system for Structural Health Monitoring to find possible damages and to see how the structure behaves over time. For...
The authors investigated the dynamic behaviour of the San Silvestro belfry in L’Aquila (Italy). T... more The authors investigated the dynamic behaviour of the San Silvestro belfry in L’Aquila (Italy). The 2009 earthquake in L’Aquila caused severe damages to the entire masonry complex. Extensive rehabilitation works, ended in 2019, repaired the structure and enhanced its seismic safety. In this paper, the authors discuss three aspects typical of masonry towers by interpreting the outcomes of Operational Modal Analysis carried out on December 2019: the interactions between the tower and the masonry complex, the dynamic effects of the bell, and the seismic reliability assessment of the tower. Specifically, the experimental mode shapes drive the estimation of an equivalent cross-section, whose principal axes of inertia match with the directions of oscillation of the mode shapes, and the parameters of an equivalent cantilevered beam roughly representative of the tower dynamics. In a second step, a two-degrees-of-freedom analytical model simulates the dynamic coupling between the tower and t...
The authors assessed the fragility functions and behavior factors of cross-laminated timber (CLT)... more The authors assessed the fragility functions and behavior factors of cross-laminated timber (CLT) structures. The structures derive from the assembly of single CLT wall panels characterized by different configurations. The extended energy-dependent generalized Bouc-Wen (EEGBW) hysteresis model describes their inelastic behavior: the experimental data obtained by Gavric et al. are used to calibrate the hysteretic models of the considered cases. The truncated incremental dynamic analysis of the building models under a set of earthquake records yields the fragility functions and behavior factors. The copious results allow a comparative study between multiple structural configurations characterized by different constructive features. The behavior factors match those already proposed by the scientific literature. An analytical relationship was estimated relating the behavior factors and a suite of parameters (e.g. joint density, slenderness ratio of the CLT panel, and number of stories) ...
Proceedings of the 7th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2015)
Structural monitoring in highly seismic areas represents a valuable source of information in both... more Structural monitoring in highly seismic areas represents a valuable source of information in both structures' behaviour understanding and identification techniques' validation. In this paper the case of a permanent monitoring system, installed in a thirteenth century monumental site, the Santa Maria of Collemaggio Basilica (Italy), is presented. Both low intensity tremors and strong motion earthquakes are recorded. Recent earthquakes provided both input (base ground accelerogram) and output (structure's response) signals. Hence a comparison has been drawn between the results from a set of Output-Only (OO) Identification techniques and a set of Input-Output (IO) algorithms. In the group of IO techniques, a rapid and easily implementable technique, based on an OLS linear regression model, is presented. Different results between the IO techniques, driven by earthquake recordings, and the OO ones, driven by ambient vibration data, emerge. Attempts are made to capture the system's dynamics, by means of a linear regression model, stressing possible research issues in the identification of non stationary systems subjected to seismic excitation. 1770 COMPDYN 2019 7 th ECCOMAS Thematic Conference on Computational Methods in Structural Dynamics and Earthquake Engineering M. Papadrakakis, M. Fragiadakis (eds.
Masonry towers, located in seismic zones, are vulnerable and prone to damages up to compromise th... more Masonry towers, located in seismic zones, are vulnerable and prone to damages up to compromise their stability. The scatter of data on the mechanical properties of masonry, geometry and boundary conditions determine a lack of building knowledge on their expected behaviour. Therefore the assessment of the seismic capacity represents a critical task. This paper contributes to the issue of seismic analysis of masonry towers, focusing a meaningful case study: the St.Silvestro belfry in L’Aquila, Italy. The tower, severely damaged by the 2009 earthquake sequence, underwent extensive restoration works, endeavoured to mitigate its vulnerability. The observed seismic damage, the performed no-destructive testing campaign and the accomplished rehabilitation measures are described in the paper. The authors appraised the actual seismic performances of the St.Silvestro belfry, reinforced by the last restoration works. At first, the Operational Modal Analysis (OMA) is carried out to enhance build...
8th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering Methods in Structural Dynamics and Earthquake Engineering
In the last decades, the applications of structural monitoring are moving toward the field of civ... more In the last decades, the applications of structural monitoring are moving toward the field of civil engineering and infrastructures. Nevertheless, if the structures have damages, it does not mean that they have a complete loss of functionality, but rather that the system is no longer in an optimal condition so that, if the damage increases, the structure can collapse. Structural Health Monitoring (SHM), a process for the identification of damage, periodically collects data from suitable sensors that allow to characterize the damage and establishes the health status of the structure. Therefore, this monitoring will provide information on the structure condition, mostly about its integrity, in a short time, and, for infrastructures and civil structures, it is necessary to assess performance and health status. The aim of this work is to design an Internet of Things (IoT) system for Structural Health Monitoring to find possible damages and to see how the structure behaves over time. For...
The authors investigated the dynamic behaviour of the San Silvestro belfry in L’Aquila (Italy). T... more The authors investigated the dynamic behaviour of the San Silvestro belfry in L’Aquila (Italy). The 2009 earthquake in L’Aquila caused severe damages to the entire masonry complex. Extensive rehabilitation works, ended in 2019, repaired the structure and enhanced its seismic safety. In this paper, the authors discuss three aspects typical of masonry towers by interpreting the outcomes of Operational Modal Analysis carried out on December 2019: the interactions between the tower and the masonry complex, the dynamic effects of the bell, and the seismic reliability assessment of the tower. Specifically, the experimental mode shapes drive the estimation of an equivalent cross-section, whose principal axes of inertia match with the directions of oscillation of the mode shapes, and the parameters of an equivalent cantilevered beam roughly representative of the tower dynamics. In a second step, a two-degrees-of-freedom analytical model simulates the dynamic coupling between the tower and t...
The authors assessed the fragility functions and behavior factors of cross-laminated timber (CLT)... more The authors assessed the fragility functions and behavior factors of cross-laminated timber (CLT) structures. The structures derive from the assembly of single CLT wall panels characterized by different configurations. The extended energy-dependent generalized Bouc-Wen (EEGBW) hysteresis model describes their inelastic behavior: the experimental data obtained by Gavric et al. are used to calibrate the hysteretic models of the considered cases. The truncated incremental dynamic analysis of the building models under a set of earthquake records yields the fragility functions and behavior factors. The copious results allow a comparative study between multiple structural configurations characterized by different constructive features. The behavior factors match those already proposed by the scientific literature. An analytical relationship was estimated relating the behavior factors and a suite of parameters (e.g. joint density, slenderness ratio of the CLT panel, and number of stories) ...
Uploads
Papers by rocco alaggio