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Seismic Assessment and Design of Structures: Volume 2

A special issue of Applied Sciences (ISSN 2076-3417). This special issue belongs to the section "Civil Engineering".

Deadline for manuscript submissions: closed (29 February 2024) | Viewed by 17309

Special Issue Editor


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Guest Editor
Department of Civil Engineering, University of Patras, 26504 Rion-Patras, Greece
Interests: seismic assessment and design of structures: nonlinear FE modelling; nonlinear static and dynamic analysis; seismic codes; building damage; performance-based earthquake engineering; structural pounding; morphological effects on structures
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Following the success achieved with the first edition of the Special Issue “Seismic Assessment and Design of Structures”, we have decided to create a second one, to continue to publish scientific research that reflects the state of the art in the field of the evaluation/verification of the seismic performance of structures through analytical, numerical and experimental approaches and the application of these seismic assessment approaches to the design of structures. Advanced computational technologies and models to perform detailed nonlinear static and/or dynamic analyses of realistic structural systems are included in the scope of this Special Issue. Contributions that involve a significant earthquake engineering component are especially welcome.

Example topics of interest include the following:

  • Nonlinear structural systems and analysis techniques for structural assessment;
  • Seismic performance of structures under single or multiple seismic hazards;
  • Probabilistic and deterministic methods in earthquake engineering assessment and design;
  • Earthquake records for the nonlinear response analysis of structures;
  • Influence of environmental and operational conditions on structural performance;
  • Experimental seismic response of structures.

Dr. Maria Favvata
Guest Editor

Manuscript Submission Information

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Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • earthquake engineering
  • structural analysis
  • seismic performance
  • seismic risk mitigation
  • seismic codes
  • nonlinear structural systems
  • inelastic response demands
  • structural damage criteria
  • performance levels
  • seismic hazards
  • behavior factors

Published Papers (14 papers)

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Research

32 pages, 11126 KiB  
Article
A Generalized Nonlinear Beam Element for Slender RC Members Using a Polygonization Section Approach—Part II: Verification of Analytical with Experimental Results
by Dimitris K. Sfondylis and Manolis G. Sfakianakis
Appl. Sci. 2024, 14(7), 2797; https://doi.org/10.3390/app14072797 - 27 Mar 2024
Viewed by 412
Abstract
The proposed mathematical model, described in detail in Part I of the present paper, aims to solve the common numerical problems that currently characterize classic fiber models when used with a moderate fiber grid for reasons of computational cost. To confirm these objectives, [...] Read more.
The proposed mathematical model, described in detail in Part I of the present paper, aims to solve the common numerical problems that currently characterize classic fiber models when used with a moderate fiber grid for reasons of computational cost. To confirm these objectives, comparisons were made between analytical predictions of the model with experimental results of RC specimens and of a 2D scaled frame for a wide range of parameters that mainly concern slender specimens without significant influence of the bond slip phenomenon, different types of cross section shapes, and various loading histories. The agreement between analytical to experimental results was found to range from very good to excellent in some cases. Full article
(This article belongs to the Special Issue Seismic Assessment and Design of Structures: Volume 2)
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0 pages, 12840 KiB  
Article
A Generalized Nonlinear Beam Element for Slender RC Members Using a Polygonization Section Approach—Part I: Theoretical Formulation
by Dimitris K. Sfondylis and Manolis G. Sfakianakis
Appl. Sci. 2024, 14(5), 2188; https://doi.org/10.3390/app14052188 - 5 Mar 2024
Cited by 1 | Viewed by 678
Abstract
A mathematical model for RC beam elements is presented that falls into the category of distributed inelasticity models discretizing the cross-section in polygons (trapezoids, triangles). The models falling into these categories are considered to be able to describe in the best manner the [...] Read more.
A mathematical model for RC beam elements is presented that falls into the category of distributed inelasticity models discretizing the cross-section in polygons (trapezoids, triangles). The models falling into these categories are considered to be able to describe in the best manner the inelastic behavior of the element across its whole clear length, since its response results from the numerical integration of the stiffnesses of its cross-sections, while presenting an ideal combination of accuracy, simplicity, and computational cost. The behavior of the cross-section is described through the constitutive relationships σε of its materials for cyclic loading. The main objectives for the development of the proposed mathematical model are as follows: (a) the increased accuracy of the results compared to existing experimental ones; (b) the limitless generalization of its application, regarding of the cross-section shape; and (c) the elimination of the numerical problems presented by the application of other related models, a fact that leads to their impractical use in real three-dimensional structures. The proposed model falls under the category of distributed inelasticity models. This paper focuses on its initial version, which targets slender beam elements with negligible shear and bond-slip effects (i.e., with ribbed bars, sufficiently anchored). Thus, it is applicable to 2D and 3D framed structures that fulfill these conditions, while its modular structure allows for future adjustments for the inclusion of other effects. Full article
(This article belongs to the Special Issue Seismic Assessment and Design of Structures: Volume 2)
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22 pages, 4774 KiB  
Article
A New Method for Defining the Optimal Separation Gap Distance and the Acceptable Structural Pounding Risk on Multistory RC Structures
by Maria G. Flenga and Maria J. Favvata
Appl. Sci. 2024, 14(3), 1165; https://doi.org/10.3390/app14031165 - 30 Jan 2024
Cited by 1 | Viewed by 542
Abstract
A proposal to control the structural pounding hazard imposed on multistory reinforced concrete (RC) structures is presented. The main goal is to guarantee the seismic performance of a structure with an acceptable (predefined) risk-targeted parameter without the need to eliminate structural pounding collisions. [...] Read more.
A proposal to control the structural pounding hazard imposed on multistory reinforced concrete (RC) structures is presented. The main goal is to guarantee the seismic performance of a structure with an acceptable (predefined) risk-targeted parameter without the need to eliminate structural pounding collisions. The key target parameters of this study are the annual probability of exceeding an engineering demand parameter (EDP) capacity level and the separation distance dg between adjacent structures. In this direction, a method that ensures the performance level of critical EDPs due to structural pounding conditions is proposed. The new method involves two decision frameworks that define (a) the optimal separation gap distance dg,minPt at a targeted value of pounding risk (probability per year) Pt (Decision A) and (b) the minimum acceptable structural pounding risk Pmindg,t at a targeted value of separation gap distance dg,t (Decision B). The demand parameters that are incorporated in the proposed method are the peak relative displacement δmax at the top level of colliding without considering pounding conditions and any other critical EDP due to the structural pounding effect. The overall method is based on two distinct acceptable performance objectives, the POs-δmax and the POs-EDP, defined as a function of P vs. dg. For this purpose, a seismic hazard curve compatible with Eurocode’s 8 hazard zone is adopted, and the corresponding demand hazard curves of δmax and EDP are developed. The proposed method is implemented to study the floor-to-floor structural pounding hazard of an eight-story RC frame taking into account different risk-targeted scenarios. The results show that the seismic risk (probability per year) of exceeding the EDP’s capacity level is significantly increased due to structural pounding in comparison to the case of no pounding. Calibration of the structural pounding risk can be obtained by adjusting the separation gap distance dg between the adjacent structures based on the acceptable POs. The POs-δmax is not always an accurate criterion for verifying the capacity level of the critical EDP. Finally, with the proposed method, a variety of POs-EDPs can be used to control the structural pounding risk in terms of dg,minPt and/or Pmindg,t. Full article
(This article belongs to the Special Issue Seismic Assessment and Design of Structures: Volume 2)
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22 pages, 8403 KiB  
Article
Seismic Upgrade of an Existing Reinforced Concrete Building Using Steel Plate Shear Walls (SPSW)
by Niki Balkamou and George Papagiannopoulos
Appl. Sci. 2024, 14(1), 443; https://doi.org/10.3390/app14010443 - 3 Jan 2024
Viewed by 1251
Abstract
Steel Plate Shear Walls (SPSW) provide significant lateral load capacity and can be utilized in the seismic retrofit and upgrade of existing reinforced concrete (r/c) buildings. In this study, the application of SPSW to retrofit a r/c building designed according to older seismic [...] Read more.
Steel Plate Shear Walls (SPSW) provide significant lateral load capacity and can be utilized in the seismic retrofit and upgrade of existing reinforced concrete (r/c) buildings. In this study, the application of SPSW to retrofit a r/c building designed according to older seismic provisions is presented. Three different options to model SPSW are utilized, i.e., by equivalent braces, by finite elements, and by membrane elements, seeking not only to appropriately simulate the actual behavior of the SPSW but also to achieve the desired seismic behavior of the retrofitted building. Specific seismic response indices, including plastic hinge formations, are derived by non-linear time-history analyses in order to assess the seismic behavior of the retrofitted r/c building. Inspection of the results provided by non-linear analyses in conjunction with the different modeling options of the SPSW leads to the conclusion that the model with the membrane elements exhibits the best performance, implying that for the seismic retrofit and upgrade of existing r/c buildings, the use of membrane elements to model the SPSW is recommended. Full article
(This article belongs to the Special Issue Seismic Assessment and Design of Structures: Volume 2)
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27 pages, 7598 KiB  
Article
A Contribution to Facilitate the Seismic Design in Lebanon Using Short-Length Spectrum-Consistent Earthquakes
by Amal Gerges, Maria Cristina Porcu and Juan Carlos Vielma Pérez
Appl. Sci. 2023, 13(24), 12990; https://doi.org/10.3390/app132412990 - 5 Dec 2023
Viewed by 1093
Abstract
Seismic regulations of developing countries are often grounded on rules of more experienced countries. The Lebanese regulations refer to four foreign codes, this excess of guidelines generating confusion and conflicting design choices. Moreover, the scarcity of earthquakes recorded in the Lebanese area makes [...] Read more.
Seismic regulations of developing countries are often grounded on rules of more experienced countries. The Lebanese regulations refer to four foreign codes, this excess of guidelines generating confusion and conflicting design choices. Moreover, the scarcity of earthquakes recorded in the Lebanese area makes it difficult to obtain suitable sets of spectrum-consistent accelerograms for dynamic analyses. Sorting through the reference regulations and the indications for their local application, this paper derives and compares all the design response spectra allowed by the Lebanese code. Consistent with the design response spectra of the two codes that are still in force (of the four referred to), some suites of spectrum-consistent accelerograms are derived. Based on the Arias intensity, a general procedure is also proposed to reduce the time duration of the accelerograms, while saving the earthquake energy content and, thus, the reliability of the results. Full-length and short-length spectrum-consistent accelerograms are thus made available for the Lebanese design. With reference to a two-dimensional model some comparisons between response-spectrum-based and earthquake-based analyses are provided, which showed that the Lebanese code allows different safety levels for earthquake-resistant buildings. The paper provides a very useful contribution to researchers and designers that are involved in the protection of the Lebanese building heritage from seismic hazards, and it also provides data and tools that can be more generally exploited in other seismic areas. Full article
(This article belongs to the Special Issue Seismic Assessment and Design of Structures: Volume 2)
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31 pages, 17565 KiB  
Article
Explicit Method in the Seismic Assessment of Unreinforced Masonry Buildings through Plane Stress Elements
by Elesban Nochebuena-Mora, Nuno Mendes, Valentina Calixto and Sandra Oliveira
Appl. Sci. 2023, 13(19), 10602; https://doi.org/10.3390/app131910602 - 22 Sep 2023
Viewed by 1074
Abstract
The complex nonlinear behaviour of unreinforced masonry (URM), along with the interaction between structural elements, still represents a challenge for the seismic assessment of existing URM buildings. A large variety of mathematical tools have been developed in the last decades to address the [...] Read more.
The complex nonlinear behaviour of unreinforced masonry (URM), along with the interaction between structural elements, still represents a challenge for the seismic assessment of existing URM buildings. A large variety of mathematical tools have been developed in the last decades to address the issue. The numerical work herein presented attempts to provide some insights into the use of FEM models to obtain reliable results from nonlinear dynamic analyses conducted with explicit methods. Through plane stress elements, two in-plane mechanisms were studied to identify optimal parameters for unreinforced masonry elements subjected to dynamic actions. The results were then compared with outcomes generated by an implicit solver. Subsequently, these parameters were used in nonlinear dynamic analyses on a building section for the seismic assessment in both unreinforced and reinforced conditions. The element type, hourglass control, damping, and bulk viscosity influence the dynamic response, mainly when the nonlinearities become larger. The hourglass control techniques employ a scaling factor to suppress the occurrence of spurious modes. Values ranging from 0.01 to 0.03 have shown effective results. When the stiffness-damping parameter for Rayleigh damping is of a similar order of magnitude or lower than the time increment without damping, the time increment remained in feasible ranges for performing analysis. Additionally, the bulk viscosity can stabilise the response without causing substantial alterations to the time increment if the values are under 1.00. Full article
(This article belongs to the Special Issue Seismic Assessment and Design of Structures: Volume 2)
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17 pages, 510 KiB  
Article
Fuzzy Multivariate Regression Models for Seismic Assessment of Rocking Structures
by Fani I. Gkountakou, Kosmas E. Bantilas, Ioannis E. Kavvadias, Anaxagoras Elenas and Basil K. Papadopoulos
Appl. Sci. 2023, 13(17), 9602; https://doi.org/10.3390/app13179602 - 24 Aug 2023
Viewed by 652
Abstract
The assessment of rocking response is a challenging task due to its high nonlinearity. The present study investigates two methodologies to evaluate finite rocking rotations and overturn of three typical rocking systems. In particular, fuzzy linear regression (FLR) with triangular fuzzy numbers and [...] Read more.
The assessment of rocking response is a challenging task due to its high nonlinearity. The present study investigates two methodologies to evaluate finite rocking rotations and overturn of three typical rocking systems. In particular, fuzzy linear regression (FLR) with triangular fuzzy numbers and a hybrid model combining logistic regression and fuzzy logic were adopted. To this end, three typical rocking structures were considered, and nonlinear time history analyses were performed to obtain their maximum response. Eighteen seismic intensity measures (IMs) extracted from recorded seismic accelerograms were considered to predict the responses. In the absence of rocking overturn, the finite rocking rotations and similarity ratios were calculated by adopting the FLR method. Moreover, extensive analysis was performed to evaluate the influence of each IM on the model’s predictions. On the other hand, rocking overturn was evaluated by logistic regression to compute the probability of collapse, followed by the FLR method to estimate the similarity between the different rocking-based structural systems. The root mean square error (RMSE) parameter and the log loss function were determined for every model to assess the predictions that emerged from the two fuzzy methods. As indicated, both methods demonstrated satisfactory results, presenting minimal deviations from the observed values. Finally, in the case of finite rocking rotation predictive models, remarkably high similarity ratios were observed among the various structures, with a median value of 0.96. Full article
(This article belongs to the Special Issue Seismic Assessment and Design of Structures: Volume 2)
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23 pages, 14593 KiB  
Article
Study on Earthquake Failure Mechanism and Failure Mode of Cable-Stayed Pipeline Bridge Considering Fluid–Structure Coupling
by Xiyu Zhu and Guangyuan Weng
Appl. Sci. 2023, 13(17), 9583; https://doi.org/10.3390/app13179583 - 24 Aug 2023
Cited by 1 | Viewed by 957
Abstract
To investigate the failure mode of the cable-stayed pipeline bridge under seismic loading, this study focuses on an oil and gas cable-stayed pipeline bridge as the research subject. A full-scale finite element calculation model of the structural system is established using ANSYS Workbench [...] Read more.
To investigate the failure mode of the cable-stayed pipeline bridge under seismic loading, this study focuses on an oil and gas cable-stayed pipeline bridge as the research subject. A full-scale finite element calculation model of the structural system is established using ANSYS Workbench 14.0 software, considering the stress characteristics and structural properties of the oil and gas pipeline. Additionally, a fluid–structure coupling effect finite element model is developed to account for the influence of medium within the pipeline. The analysis includes evaluating deformation, stress, strain, and other responses of the oil and gas pipeline subjected to seismic waves from different directions. The results indicate that the overall damage in the pipeline is consistent with maximum deformation, stress, and strain, concentrated at both the inlet/outlet ends and side spans; however, variations exist in terms of seismic damage depending on wave directionality. Furthermore, by considering interactions between various components within the oil and gas cable-stayed pipeline bridge’s structural system during strong earthquakes, this study analyzes failure mechanisms caused by the support–pipeline interaction as well as excessive displacement-induced failure patterns in bridge towers. Finally, a proposed failure mode for pipe bridge systems resulting from longitudinal slip between supports and pipelines, along with excessive displacement of bridge towers, is presented. Full article
(This article belongs to the Special Issue Seismic Assessment and Design of Structures: Volume 2)
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18 pages, 5137 KiB  
Article
On the Role of Seismic Damage Tolerance on Costs and Life Cycle of CLT Buildings
by Simona Iezzi, Francesca Savini, Ilaria Trizio, Giovanni Fabbrocino and Antonio Sandoli
Appl. Sci. 2023, 13(16), 9113; https://doi.org/10.3390/app13169113 - 10 Aug 2023
Viewed by 969
Abstract
This paper presents a contribution to reviewing the most common seismic design procedures of CLT buildings and their implications on structural features and technological solutions. Attention is particularly focused on the overall seismic performance, damage tolerance, construction costs and environmental impact. It is [...] Read more.
This paper presents a contribution to reviewing the most common seismic design procedures of CLT buildings and their implications on structural features and technological solutions. Attention is particularly focused on the overall seismic performance, damage tolerance, construction costs and environmental impact. It is intended as a baseline for a more comprehensive study, thus the assessment is made with reference to a real building, representative of a class of common buildings recently designed and erected in many Italian regions exposed to low and moderate seismic hazards. As usual, the analysis was carried out according to a two-dimensional model of the panels, assumed to be elastic, varying the type of connections at the base, the presence of pre-stressing steel bars for rocking control and dissipative devices. The main outcomes of the study can be summarized as follows: (i) the structural seismic behavior of CLT buildings is significantly influenced by the structural schemes adopted for walls and connections; (ii) construction costs and environmental impact decrease whenever damage tolerance is accounted for in design procedures. Full article
(This article belongs to the Special Issue Seismic Assessment and Design of Structures: Volume 2)
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15 pages, 5817 KiB  
Article
Masonry Arch Bridges with Finite Compression Strength Subject to Horizontal Longitudinal Seismic Actions
by Paolo Clemente, Fernando Saitta, Giacomo Buffarini and Chiara Ormando
Appl. Sci. 2023, 13(13), 7509; https://doi.org/10.3390/app13137509 - 25 Jun 2023
Cited by 2 | Viewed by 857
Abstract
The great diffusion of masonry arch bridges, sometimes of historical interest, requires the development of simple but effective methodologies for a preliminary but reliable evaluation of their static and seismic capacity. In this paper, the behaviour under longitudinal seismic actions is analysed by [...] Read more.
The great diffusion of masonry arch bridges, sometimes of historical interest, requires the development of simple but effective methodologies for a preliminary but reliable evaluation of their static and seismic capacity. In this paper, the behaviour under longitudinal seismic actions is analysed by using the mechanism method. The masonry is supposed to have no tension strength but a rigid–perfect plastic behaviour with finite strength in compression. The arch is subject to permanent loads and to a horizontal acceleration acting in the longitudinal direction, which causes a horizontal inertial loading acting on the arch. Three hypotheses about the effects of the inertial actions of the backfill are considered, which correspond to three different real behaviours. A comprehensive numerical investigation is performed, which allows us to point out the influence of the geometrical and mechanical parameters on the seismic capacity of a masonry arch bridge. The results are given by means of diagrams that can be easily used for a preliminary seismic check of a masonry arch bridge. Full article
(This article belongs to the Special Issue Seismic Assessment and Design of Structures: Volume 2)
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24 pages, 1489 KiB  
Article
Effectiveness of Tuned Mass Damper in Reducing Damage Caused by Strong Earthquake in a Medium-Rise Building
by Lucas Mazzon, Giada Frappa and Margherita Pauletta
Appl. Sci. 2023, 13(11), 6815; https://doi.org/10.3390/app13116815 - 4 Jun 2023
Cited by 3 | Viewed by 3113
Abstract
A case study where a tuned mass damper (TMD) was installed at the top of a five-story reinforced concrete (RC) building is presented. The aim of the study was to investigate the effectiveness of the TMD in changing the structural behavior of medium-rise [...] Read more.
A case study where a tuned mass damper (TMD) was installed at the top of a five-story reinforced concrete (RC) building is presented. The aim of the study was to investigate the effectiveness of the TMD in changing the structural behavior of medium-rise existing buildings from dissipative to non-dissipative in order to eliminate reparation or demolition costs resulting from damages caused by strong earthquakes. The TMD mass is made by a RC slab lying on flat surface sliders. Horizontal stiffness and damping of the TMD are both provided by lead rubber isolators in the first proposed solution and by low-damping rubber isolators and viscous linear dampers, respectively, in the second. The improvement in the building’s structural behavior attained with the installation of the TMD was assessed by considering the flexural demand over capacity ratios of structural elements and the energy dissipated by the TMD. These results are compared with those of the same building retrofitted with a base isolation system. In both of the proposed solutions, TMD remarkably changed the modal behavior of the considered building, improved the flexural verifications, and dissipated most of the input seismic energy. It is therefore demonstrated that a TMD is a valid solution for the retrofit of medium-rise existing buildings. Full article
(This article belongs to the Special Issue Seismic Assessment and Design of Structures: Volume 2)
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18 pages, 9639 KiB  
Article
Numerical Analysis of Seismic Pounding between Adjacent Buildings Accounting for SSI
by Mehmet Eren Uz, Anna Jakubczyk-Gałczyńska and Robert Jankowski
Appl. Sci. 2023, 13(5), 3092; https://doi.org/10.3390/app13053092 - 27 Feb 2023
Cited by 3 | Viewed by 1556
Abstract
The structural pounding caused by an earthquake may damage structures and lead to their collapse. This study is focused on the pounding between two adjacent asymmetric structures with different dynamic properties resting on the surface of an elastic half-space. An exploration of the [...] Read more.
The structural pounding caused by an earthquake may damage structures and lead to their collapse. This study is focused on the pounding between two adjacent asymmetric structures with different dynamic properties resting on the surface of an elastic half-space. An exploration of the relationship between the effects of the seismic analysis with the impact response to the torsional pounding between adjacent buildings under different SSI effects has been presented. In this paper, the authors have proposed a procedure for analyzing the response for adjacent buildings subjected to the pounding effects, considering systems with multiple degrees of freedom and modal equations of motion with four types of soil. All the calculations have been performed based on the fourth-order Runge–Kutta method. The novelty of the present study is related to the fact that the rigorous and approximate methods are used to examine the effects of pounding and SSI simultaneously. As a result, these two methods have been thoroughly investigated for both effects and the results have been compared. The results show that the approximate method produces results that are slightly different from those obtained by the rigorous direct integration method in the case of small SSI effects due to an increase in the pounding force. The efficiency of the method is also validated using numerical examples. Full article
(This article belongs to the Special Issue Seismic Assessment and Design of Structures: Volume 2)
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21 pages, 6415 KiB  
Article
Seismic Upgrade of Steel Frame Buildings by Using Damped Braces
by Eleonora Bruschi, Virginio Quaglini and Luca Zoccolini
Appl. Sci. 2023, 13(4), 2063; https://doi.org/10.3390/app13042063 - 5 Feb 2023
Cited by 12 | Viewed by 1677
Abstract
Supplementary energy dissipation has proved to be an effective way of protecting structures from the disastrous effects of earthquakes and has been used in the last decades both in new and in existing constructions. In this regard, various procedures for the design of [...] Read more.
Supplementary energy dissipation has proved to be an effective way of protecting structures from the disastrous effects of earthquakes and has been used in the last decades both in new and in existing constructions. In this regard, various procedures for the design of the damping system for the seismic retrofit of buildings have been formulated over the years, mainly focused on reinforced concrete (RC) constructions, which represent the largest part of the existing stock in many seismic-prone countries. The study deals with the assessment of a displacement-based design procedure for proportioning the damping system recently proposed in the literature for RC framed buildings, with the goal of establishing a good practice for the application of the procedure to steel buildings as well. The method was applied to three case-study frames, regular in plan and in elevation, which were assumed as being representative of old structures designed without consideration of seismic requirements. The retrofit was performed by using chevron braces equipped with dampers with an elastic-perfectly plastic behavior. The method aimed at defining the properties of the dampers to achieve a target performance in terms of the maximum lateral deflection for a specific level of seismic intensity. The effectiveness and reliability of the proposed procedure was eventually assessed by evaluating the seismic performance of the upgraded steel structures in static and dynamic non-linear analyses. Full article
(This article belongs to the Special Issue Seismic Assessment and Design of Structures: Volume 2)
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16 pages, 3463 KiB  
Article
Hilbert–Huang-Transform-Based Seismic Intensity Measures for Rocking Response Assessment
by Kosmas E. Bantilas, Ioannis E. Kavvadias, Magdalini Tyrtaiou and Anaxagoras Elenas
Appl. Sci. 2023, 13(3), 1634; https://doi.org/10.3390/app13031634 - 27 Jan 2023
Cited by 1 | Viewed by 942
Abstract
Structures that can uplift and rock under severe seismic excitations present remarkable stability without exhibiting damage. As such, rocking-response-based structural systems constitute a promising design practice. Due to the high nonlinearity of the rocking response, the seismic performance of this class of structures [...] Read more.
Structures that can uplift and rock under severe seismic excitations present remarkable stability without exhibiting damage. As such, rocking-response-based structural systems constitute a promising design practice. Due to the high nonlinearity of the rocking response, the seismic performance of this class of structures should be evaluated probabilistically. From this point of view, in the present study, the performance of 12 novel HHT-based intensity measures (IMs) in describing the seismic behavior of typical rocking viaducts was assessed based on optimal IM selection criteria. To this end, a comparative evaluation of the performance between the proposed and 26 well-known conventional IMs was presented. Moreover, bivariate IMs were also considered, and seismic fragilities were provided. Finally, the classification of the seismic response was conducted using discriminant analysis, resulting in a reliable and rapid estimation of the maximum seismic demand. Based on the results, it is evident that HHT-based IMs result in an enhanced estimation of the seismic performance of the examined structural system. Full article
(This article belongs to the Special Issue Seismic Assessment and Design of Structures: Volume 2)
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