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The shear properties are key characteristics for evaluating masonry elements under in-plane horizontal actions. Historical structures may need the evaluation of these properties in order to perform safety evaluations, diagnoses, retrofitting, etc. These properties are often difficult to estimate and may be measured using Destructive Testing (DT) methods, which are not always compatible with the structure under test, either because of the cultural value, the high cost or the excessive damage introduced. Therefore, this paper addresses a Minor Destructive Testing (MDT) technique with the purpose of measuring masonry shear properties. This represents a first contribution to a universally adopted and accepted MDT technique, which is not currently available. The present paper aims to study in detail the experimental results of four shear Flat Jack (FJ) tests from literature, by means of linear and non-linear analyses performed using micro and macro Finite Element models. These analyses are meant to study the ability of the shear FJ test for evaluating the shear modulus and the diagonal tensile strength of unreinforced brick masonry. The numerical results highlight the potential for the shear FJ test to become a suitable MDT method for evaluating the shear modulus and strength of brick masonry and evidence some aspects where further investigation is advisable.
Nicola Viale; Giulio Ventura; Paulo B. Lourenço; Javier Ortega. Linear and non-linear FEM analyses to assess a shear flat-jack test for masonries. Journal of Building Engineering 2021, 103169 .
AMA StyleNicola Viale, Giulio Ventura, Paulo B. Lourenço, Javier Ortega. Linear and non-linear FEM analyses to assess a shear flat-jack test for masonries. Journal of Building Engineering. 2021; ():103169.
Chicago/Turabian StyleNicola Viale; Giulio Ventura; Paulo B. Lourenço; Javier Ortega. 2021. "Linear and non-linear FEM analyses to assess a shear flat-jack test for masonries." Journal of Building Engineering , no. : 103169.
Displacement-based methods contained in recent standards for seismic safety assessment require the determination of the full nonlinear pushover curve for local failure mechanisms in historic masonry structures. This curve should reflect both the initial elastic behavior and the rigid body behavior after the activation of rocking. In this work, a rigid block model is proposed for the displacement-based seismic assessment of local collapse mechanisms of these structures. Masonry is modeled as an assemblage of two-dimensional rigid blocks in contact through frictional interfaces. Two types of contact models are formulated to capture, respectively, the pre and postpeak branches of the pushover curve: a unilateral elastic contact model, capturing the initial nonlinear behavior up to the force capacity of the structure, corresponding to the activation of the collapse mechanism, and a rigid contact model with finite friction and compressive strength, which describes the rigid-body rocking behavior up to the attainment of the displacement capacity of the structure. Tension-only elements are also implemented to model strengthening interventions with tie-rods. The contact problems associated with the elastic and rigid contact models are formulated using mathematical programming. For both models, a sequential solution procedure is implemented to capture the variation of the load multiplier with the increasing deformation of the structure (P–Δ effect). The accuracy of the modeling approach in reproducing the pushover curve of masonry panels subjected to horizontal seismic loads is evaluated on selected case studies. The solution is first tested against hand calculations, existing analytical models, and distinct element simulations. Then, comparisons against experimental tests follow. As a final application, the failure mechanism and pushover curve of a triumphal masonry arch are predicted by the model and its seismic assessment is performed according to codified force- and displacement-based methods, demonstrating the adequacy of the proposed tool for practice.
Francesco P. A. Portioli; Michele Godio; Chiara Calderini; Paulo B. Lourenço. A variational rigid‐block modeling approach to nonlinear elastic and kinematic analysis of failure mechanisms in historic masonry structures subjected to lateral loads. Earthquake Engineering & Structural Dynamics 2021, 1 .
AMA StyleFrancesco P. A. Portioli, Michele Godio, Chiara Calderini, Paulo B. Lourenço. A variational rigid‐block modeling approach to nonlinear elastic and kinematic analysis of failure mechanisms in historic masonry structures subjected to lateral loads. Earthquake Engineering & Structural Dynamics. 2021; ():1.
Chicago/Turabian StyleFrancesco P. A. Portioli; Michele Godio; Chiara Calderini; Paulo B. Lourenço. 2021. "A variational rigid‐block modeling approach to nonlinear elastic and kinematic analysis of failure mechanisms in historic masonry structures subjected to lateral loads." Earthquake Engineering & Structural Dynamics , no. : 1.
The primary objective is to present the most representative types of damage observed in reinforced concrete (RC) structures due to earthquakes. Those damages are divided according to the ten most representative types. Examples and the main reasons that could trigger each failure mechanism are presented. The definition of these damage types is supported by post-earthquake damage reconnaissance missions in Sichuan (China) in 2008, L’Aquila (Italy) in 2009, Lorca (Spain) in 2011, Emilia-Romagna (Italy) in 2012, Gorkha (Nepal) in 2015, Muisne (Ecuador) in 2016 and Chiapas (Mexico) in 2017. An extensive discussion is presented concerning the infill walls’ seismic behaviour and their interaction with the RC structural elements. The presentation of the significant learnings and findings concerning the typical damage herein presented and discussed are compared with the common Southern European construction practice. The impact of the infill walls on the rehabilitation costs of damaged RC buildings is also studied. These costs are compared to those related to the structural damage and rehabilitation of the entire building structure to understand the impact of the infill walls. Finally, a case study is presented to study the effect of implementing simplified retrofitting strategies to prevent the soft-storey mechanism, one of the most common problems observed in past earthquake events.
André Furtado; Hugo Rodrigues; António Arêde; Humberto Varum. A Review of the Performance of Infilled RC Structures in Recent Earthquakes. Applied Sciences 2021, 11, 5889 .
AMA StyleAndré Furtado, Hugo Rodrigues, António Arêde, Humberto Varum. A Review of the Performance of Infilled RC Structures in Recent Earthquakes. Applied Sciences. 2021; 11 (13):5889.
Chicago/Turabian StyleAndré Furtado; Hugo Rodrigues; António Arêde; Humberto Varum. 2021. "A Review of the Performance of Infilled RC Structures in Recent Earthquakes." Applied Sciences 11, no. 13: 5889.
Past earthquakes have brought attention to the poor performance of precast reinforced concrete structures, especially relating to beam-to-column connections. The evaluation of different methodologies for the analysis of beam-to-column connections in industrial buildings is important. In the present work numerical analyses developed allowed the study of the effect that different story heights and connection properties have on frequencies, drifts, seismic coefficients and connection sliding. The results showed that the friction between concrete elements and the consideration of neoprene have a small impact on the drift demands in the columns and the seismic coefficients of the structures analyzed; on the other hand, the effect of steel dowel on the drift demands and seismic coefficients is significant. The comparison of models with different properties and connections allowed a better understanding of the parameters that affect the seismic behavior of precast reinforced concrete buildings the most and provide indications for building more accurate and efficient numerical models.
Hugo Rodrigues; Hugo Vitorino; Nádia Batalha; Romain Sousa; Paulo Fernandes; Humberto Varum. Influence of Beam-to-Column Connections in the Seismic Performance of Precast Concrete Industrial Facilities. Structural Engineering International 2021, 1 -13.
AMA StyleHugo Rodrigues, Hugo Vitorino, Nádia Batalha, Romain Sousa, Paulo Fernandes, Humberto Varum. Influence of Beam-to-Column Connections in the Seismic Performance of Precast Concrete Industrial Facilities. Structural Engineering International. 2021; ():1-13.
Chicago/Turabian StyleHugo Rodrigues; Hugo Vitorino; Nádia Batalha; Romain Sousa; Paulo Fernandes; Humberto Varum. 2021. "Influence of Beam-to-Column Connections in the Seismic Performance of Precast Concrete Industrial Facilities." Structural Engineering International , no. : 1-13.
Churches in Yucatan region in Mexico are considered a built heritage legacy of great cultural interest. Some of these churches exhibit some pathologies with deformation mainly located at the stone masonry vaults. The churches are mostly built with ruble stone masonry walls and vaults in which limestone and lime mortar predominate. The design of any intervention on this type of structure requires the knowledge on the masonry materials, but very scarce information exist on the properties of limestone and lime mortar used in the construction of the churches. Therefore, the characterization of the existing materials, namely the limestone is considered to be of great interest. This research aims at the characterization of limestones found in masonry churches from sixteenth to eighteenth centuries located in Yucatan region in Mexico. To achieve the objectives, an experimental campaign was designed with the following steps: (1) identification of churches under ruins and in situ collection of stone specimens, (2) characterization of physical and mechanical properties on the collected specimens; (3) evaluation of the mineralogical composition of limestones and petrography description; (4) assessment of correlation between physical and mechanical properties. It was found that the limestones studied were mainly composed of calcium carbonate (CaCO3) and based on the physical properties, it was possible to group them in three different groups. It was also found that different ranges for the compressive strength and modulus of elasticity were obtained for the limestone belonging to each group defined. The relation between physical and mechanical properties was analyzed by a set of statistic correlations, for which very reasonable coefficients of determination were found.
Isis Rodríguez Pérez; Graça Vasconcelos; Paulo B. Lourenço; Patricia Quintana; Claudia García; Amélia Dionísio. Physical-mechanical characterization of limestones from Yucatan churches, Mexico. Journal of Building Engineering 2021, 44, 102895 .
AMA StyleIsis Rodríguez Pérez, Graça Vasconcelos, Paulo B. Lourenço, Patricia Quintana, Claudia García, Amélia Dionísio. Physical-mechanical characterization of limestones from Yucatan churches, Mexico. Journal of Building Engineering. 2021; 44 ():102895.
Chicago/Turabian StyleIsis Rodríguez Pérez; Graça Vasconcelos; Paulo B. Lourenço; Patricia Quintana; Claudia García; Amélia Dionísio. 2021. "Physical-mechanical characterization of limestones from Yucatan churches, Mexico." Journal of Building Engineering 44, no. : 102895.
The computational prediction of the out-of-plane behaviour of unreinforced masonry walls is a challenge. However, computational numerical models may provide, if properly calibrated, a powerful tool to predict the behaviour of new retrofit techniques. This paper presents the Finite Element (FE) modelling of masonry walls retrofitted with oriented strand boards (OSB) aiming the prediction of its out-of-plane behaviour. Such retrofit measure has been proposed by the authors for brick masonry walls and its efficiency has been demonstrated through experimental studies on small-scale and larger-scale masonry specimens (out-of-plane monotonic tests). The data gathered in the experimental phase has been used here to calibrate the numerical FE-based models (i.e. non-retrofitted and retrofitted). For this purpose, a detailed micro-modelling strategy has been followed assuming a perfect bond between mortar joints and brick units. The so-called Concrete Damage Plasticity (CDP) model has been adopted to describe the constitutive relation of the masonry and the OSB timber panel. The connection between the masonry and the OSB panel has been modelled through elastic anchors. Numerical results show a good agreement with the experimental data, in terms of observed damage pattern and capacity curve (within 10% difference). The calibrated numerical model has been instrumental in developing a parametric analysis to study the effect of different OSB thicknesses, the side of the application of retrofit, and the spacing between connections through anchor rods. These revealed that the out-of-plane capacity of the system is directly proportional to the OSB thickness and that the spacing between steel connectors should be lower than 500 mm for an adequate response.
Jamiu A. Dauda; Luis C. Silva; Paulo B. Lourenço; Ornella Iuorio. Out-of-plane loaded masonry walls retrofitted with oriented strand boards: Numerical analysis and influencing parameters. Engineering Structures 2021, 243, 112683 .
AMA StyleJamiu A. Dauda, Luis C. Silva, Paulo B. Lourenço, Ornella Iuorio. Out-of-plane loaded masonry walls retrofitted with oriented strand boards: Numerical analysis and influencing parameters. Engineering Structures. 2021; 243 ():112683.
Chicago/Turabian StyleJamiu A. Dauda; Luis C. Silva; Paulo B. Lourenço; Ornella Iuorio. 2021. "Out-of-plane loaded masonry walls retrofitted with oriented strand boards: Numerical analysis and influencing parameters." Engineering Structures 243, no. : 112683.
Archaeological buried structures have received less attention than aboveground historical structures, which seems evident given the visual impact of the latter. Archaeological structures present specific issues related to stability during excavation and after being exposed. This paper addresses a UNESCO world heritage site in Honduras (Copan), which has about 4 km of tunnels in a complex organization that were dug, in the last 100 years, for the purpose of investigation of buried structures under a temple complex. The objective of this work is to assess the safety of the tunnels, helping on the decision of back-filling the tunnels, adding new masonry linings and allowing access in current conditions (possibly with measures to avoid water infiltration). First, the long network of tunnels was categorized into different sections either in an earthen fill only or in presence of a masonry lining. Then, the stability of these sections was discussed as a function of the increase of soil saturation. It was found that unlined tunnels safety is likely to be compromised for a saturation higher than 70%, whereas lined tunnels do not fail when the soil becomes fully saturated, as far as drainage is ensured. Finally, this work allowed to issue recommendations on actions related to the site.
F. Pires; E. Bilotta; A. Flora; P. B. Lourenço. Assessment of Excavated Tunnels Stability in the Maya Archeological Area of Copán, Honduras. International Journal of Architectural Heritage 2021, 1 -19.
AMA StyleF. Pires, E. Bilotta, A. Flora, P. B. Lourenço. Assessment of Excavated Tunnels Stability in the Maya Archeological Area of Copán, Honduras. International Journal of Architectural Heritage. 2021; ():1-19.
Chicago/Turabian StyleF. Pires; E. Bilotta; A. Flora; P. B. Lourenço. 2021. "Assessment of Excavated Tunnels Stability in the Maya Archeological Area of Copán, Honduras." International Journal of Architectural Heritage , no. : 1-19.
The seismic performance of reinforced concrete (RC) structures are highly influence by the cyclic performance of the beam-column joints. The experimental seismic assessment of RC beam-column joints has been made essentially by cyclic tests performed on set-ups that do not totally simulate the real seismic loading and constrains conditions. A complex monitoring scheme is used to record the applied loads, reactions, joint distortion, strains on the reinforcement, lateral and axial displacements on the entire specimen, rotations and surface strains by using digital image correlation (DIC). The use of DIC is particularly important to record the strains on CFRP used to wrap the columns and beams. Based on the data recorded during the tests, it is possible compute moments; rotations and curvatures of the columns and beams; joint shear; dissipated energy by beams, columns and joint; yield displacement; ductility; peak-to-peak stiffness degradation; post-peak softening; and inter-cycle strength degradation. The innovative experimental set-up herein presented has the following advantages compared with others:
José Melo; Daniel A. Pohoryles; Tiziana Rossetto; Humberto Varum. Full-scale cyclic testing of realistic reinforced-concrete beam-column joints. MethodsX 2021, 8, 101409 .
AMA StyleJosé Melo, Daniel A. Pohoryles, Tiziana Rossetto, Humberto Varum. Full-scale cyclic testing of realistic reinforced-concrete beam-column joints. MethodsX. 2021; 8 ():101409.
Chicago/Turabian StyleJosé Melo; Daniel A. Pohoryles; Tiziana Rossetto; Humberto Varum. 2021. "Full-scale cyclic testing of realistic reinforced-concrete beam-column joints." MethodsX 8, no. : 101409.
The concept of vulnerability of the existing building stock is receiving increasing awareness and central importance in the scientific community working in earthquake risk mitigation. This assumes even more relevance when dealing with heritage structures located in relevant seismic hazard zones. The present paper aims to identify and describe the earthquake resistant features found in a unique masonry church in Ischia (Italy), and discuss their effectiveness on the impact of the post-seismic damage through the application of non-linear static analyses. The Santa Maria Maddalena Church represents one of the rare examples in which the technology of the Borbonic casa Baraccata (mixed timber-masonry construction), already well-known in the literature for its use in Italian seismic areas since the 18th century, is applied with the non-conventional combination of masonry and iron frames. The church was struck by the recent earthquake of 21th August 2017 with epicentre in Casamicciola Terme. The recorded post-seismic damage of the church evidenced non-relevant structural crack patterns, which are likely to be related to the efficacy of the construction system adopted.
Beatrice Di Napoli; Maria Pia Ciocci; Thomas Celano; Luca U. Argiento; Claudia Casapulla; Paulo B. Lourenço. Seismic behaviour of a mixed iron-masonry church: Santa Maria Maddalena, Ischia. Proceedings of the Institution of Civil Engineers - Engineering and Computational Mechanics 2021, 174, 114 -129.
AMA StyleBeatrice Di Napoli, Maria Pia Ciocci, Thomas Celano, Luca U. Argiento, Claudia Casapulla, Paulo B. Lourenço. Seismic behaviour of a mixed iron-masonry church: Santa Maria Maddalena, Ischia. Proceedings of the Institution of Civil Engineers - Engineering and Computational Mechanics. 2021; 174 (2):114-129.
Chicago/Turabian StyleBeatrice Di Napoli; Maria Pia Ciocci; Thomas Celano; Luca U. Argiento; Claudia Casapulla; Paulo B. Lourenço. 2021. "Seismic behaviour of a mixed iron-masonry church: Santa Maria Maddalena, Ischia." Proceedings of the Institution of Civil Engineers - Engineering and Computational Mechanics 174, no. 2: 114-129.
Chimneys are architectural elements of difficult access and analysis in heritage buildings. This paper presents a method for automatic modelling of round brick chimneys and analysing their inclination, straightness and surface. The method uses as input data point clouds acquired with a Terrestrial Laser Scanner. Four chimneys have been surveyed on the north face of Bragança Dukes’ Palace in Guimarães, Portugal. The method consists of two main processes. First, the point cloud of each chimney is segmented into circumferential sections and adjusted to cylinders by applying Maximum Likelihood Sample Consensus. From the set of centroids, the inclination and the straightness of the chimney is estimated. Second, the point cloud chimney is segmented longitudinally and adjusted to finite planes. The distance estimation between the input point cloud and the modelled planes allows detecting the lack of bricks or mortar erosions. The proposed method allows estimating characteristics in chimneys even if the chimneys have not been completely acquired.
Jesús Balado; Lucía Díaz-Vilariño; Miguel Azenha; Paulo B. Lourenço. Automatic Detection of Surface Damage in Round Brick Chimneys by Finite Plane Modelling from Terrestrial Laser Scanning Point Clouds. Case Study of Bragança Dukes’ Palace, Guimarães, Portugal. International Journal of Architectural Heritage 2021, 1 -15.
AMA StyleJesús Balado, Lucía Díaz-Vilariño, Miguel Azenha, Paulo B. Lourenço. Automatic Detection of Surface Damage in Round Brick Chimneys by Finite Plane Modelling from Terrestrial Laser Scanning Point Clouds. Case Study of Bragança Dukes’ Palace, Guimarães, Portugal. International Journal of Architectural Heritage. 2021; ():1-15.
Chicago/Turabian StyleJesús Balado; Lucía Díaz-Vilariño; Miguel Azenha; Paulo B. Lourenço. 2021. "Automatic Detection of Surface Damage in Round Brick Chimneys by Finite Plane Modelling from Terrestrial Laser Scanning Point Clouds. Case Study of Bragança Dukes’ Palace, Guimarães, Portugal." International Journal of Architectural Heritage , no. : 1-15.
Jamiu Adetayo Dauda; Paulo B. Lourenço; Ornella Iuorio. Out-of-plane testing of masonry walls retrofitted with oriented strand board timber panels. Proceedings of the Institution of Civil Engineers - Structures and Buildings 2021, 174, 403 -417.
AMA StyleJamiu Adetayo Dauda, Paulo B. Lourenço, Ornella Iuorio. Out-of-plane testing of masonry walls retrofitted with oriented strand board timber panels. Proceedings of the Institution of Civil Engineers - Structures and Buildings. 2021; 174 (5):403-417.
Chicago/Turabian StyleJamiu Adetayo Dauda; Paulo B. Lourenço; Ornella Iuorio. 2021. "Out-of-plane testing of masonry walls retrofitted with oriented strand board timber panels." Proceedings of the Institution of Civil Engineers - Structures and Buildings 174, no. 5: 403-417.
Nonlinear finite element models, whenever is possible, shall be validated using experimental data. The efficiency of the nonlinear analysis depends on the choice of finite element models parameters. In the present work the calibration is conducted with the goal of observe and minimize the difference between the experimental data and the nonlinear finite element models, using two distributed plasticity modelling approaches. Several models with different parameters of distributed plasticity are used herein and compared against experimental data. The results show that the nonlinear analysis, when associated to a proper modeling strategy, is capable to successfully simulate experimental data.
Helder Maranhão; Humberto Varum; Mário Pimentel. Nonlinear Finite Element Model Calibration of a Reinforced Concrete Column with Distributed Plasticity. U.Porto Journal of Engineering 2021, 7, 114 -125.
AMA StyleHelder Maranhão, Humberto Varum, Mário Pimentel. Nonlinear Finite Element Model Calibration of a Reinforced Concrete Column with Distributed Plasticity. U.Porto Journal of Engineering. 2021; 7 (3):114-125.
Chicago/Turabian StyleHelder Maranhão; Humberto Varum; Mário Pimentel. 2021. "Nonlinear Finite Element Model Calibration of a Reinforced Concrete Column with Distributed Plasticity." U.Porto Journal of Engineering 7, no. 3: 114-125.
Vessels used in industrial high temperature processes of steel and cement production are protected by refractory linings built with dry-stacked masonry, which plays a crucial role on the overall behaviour of the vessels. This paper presents the results of an experimental and numerical research on dry-joint refractory masonry subjected to uniaxial compression. Its main purpose is to fully characterize the masonry walls at different temperatures and different loading conditions. Several aspects that may influence the behaviour of these walls have been tested, namely the loadbearing capacity, the behaviour under cyclic loading and the restrained thermal elongation. The experimental results allowed to identify the effects of the stress concentrations caused by brick’s height imperfections in the mechanical behaviour of the bricks and in the loadbearing capacity of the specimens, the evolution of the wall’s Young’s modulus with the load application, the developed crack patterns and the mechanical behaviour of the samples at ambient and high temperatures. Numerical models were also developed to simulate the behaviour of the walls under different testing conditions and a good agreement with the experimental results was obtained. The concrete damaged plasticity model, using a micro-modelling approach, proved to be suitable for representing the behaviour of these walls at ambient and high temperatures.
Rafael L.G. Oliveira; João Paulo C. Rodrigues; João M. Pereira; Paulo B. Lourenço; Hans Ulrich Marschall. Thermomechanical behaviour of refractory dry-stacked masonry walls under uniaxial compression. Engineering Structures 2021, 240, 112361 .
AMA StyleRafael L.G. Oliveira, João Paulo C. Rodrigues, João M. Pereira, Paulo B. Lourenço, Hans Ulrich Marschall. Thermomechanical behaviour of refractory dry-stacked masonry walls under uniaxial compression. Engineering Structures. 2021; 240 ():112361.
Chicago/Turabian StyleRafael L.G. Oliveira; João Paulo C. Rodrigues; João M. Pereira; Paulo B. Lourenço; Hans Ulrich Marschall. 2021. "Thermomechanical behaviour of refractory dry-stacked masonry walls under uniaxial compression." Engineering Structures 240, no. : 112361.
This work aims to the deepening of technical and scientific knowledge related to the characterization of granite masonry based on geophysical, mechanical techniques and neural networks. For this, we used a method based on non-destructive testing for the characterization of traditional stone masonry and further obtaining information regarding the mechanical parameters of these elements. Widely built in stone masonry, buildings of historical interest are material goods that make up the Urban Heritage. Due to the historical and cultural value that these buildings represent, maintenance and rehabilitation work is important to maintain the appreciation of history. The preservation of buildings classified as historical and cultural heritage is of collective interest, as they mark the history of society. Considering the research object as traditional construction, it is not recommended to use destructive investigative techniques. Thus, a mechanical characterization simulation tool with the aid of Artificial Neural Networks (ANN) was developed which can be used in traditional granite walls. This database was built using tests with GPR (Ground Penetrating Radar) and sonic tests, (ST), for the characterization of samples of walls built and analyzed in a controlled environment, and the parameter used in response to the ANNs was the value of the elastic modulus. Two case studies carried out in Portugal are presented, for which this methodology was used as a non-destructive characterization tool (NDT) for traditional granite masonry buildings. In the Mancelos church and in a Miguel Bombarda street building, the application of the ANNs was made based on the results of the sonic tests and the GPR. This confirms the feasibility of using these simulation tools to assist in the characterization processes of traditional and historic buildings with granite stone masonry.
Rachel Martini; Jorge Carvalho; António Arêde; Humberto Varum. Validation of nondestructive methods for assessing stone masonry using artificial neural networks. Journal of Building Engineering 2021, 42, 102469 .
AMA StyleRachel Martini, Jorge Carvalho, António Arêde, Humberto Varum. Validation of nondestructive methods for assessing stone masonry using artificial neural networks. Journal of Building Engineering. 2021; 42 ():102469.
Chicago/Turabian StyleRachel Martini; Jorge Carvalho; António Arêde; Humberto Varum. 2021. "Validation of nondestructive methods for assessing stone masonry using artificial neural networks." Journal of Building Engineering 42, no. : 102469.
Performance-based design plays a significant role in the structural and earthquake engineering community to ensure both safety and economic feasibility. Its application to masonry building design/assessment is limited and requires straightforward rules considering the characteristics of masonry behavior. Nonlinear static procedures mainly cover regular frame system structures, and their application to both regular and irregular masonry buildings require further investigation. The present paper addresses two major issues: (i) the definition of irregularity in masonry buildings, and (ii) the applicability of classical nonlinear static procedures to irregular masonry buildings. It is observed that the irregularity definition is not comprehensive and has different descriptions among the seismic codes as well as among researchers, particularly in the case of masonry buildings. The lack of global language may result in the misuse of the procedures, while adjustments may be essential due to irregularity effects. Therefore, irregularity indices given by different codes and research studies are discussed. Furthermore, an overview of nonlinear static procedures implemented within the framework of the performance-based approach and improvements proposed for its application in masonry buildings is presented.
Abide Aşıkoğlu; Graça Vasconcelos; Paulo Lourenço. Overview on the Nonlinear Static Procedures and Performance-Based Approach on Modern Unreinforced Masonry Buildings with Structural Irregularity. Buildings 2021, 11, 147 .
AMA StyleAbide Aşıkoğlu, Graça Vasconcelos, Paulo Lourenço. Overview on the Nonlinear Static Procedures and Performance-Based Approach on Modern Unreinforced Masonry Buildings with Structural Irregularity. Buildings. 2021; 11 (4):147.
Chicago/Turabian StyleAbide Aşıkoğlu; Graça Vasconcelos; Paulo Lourenço. 2021. "Overview on the Nonlinear Static Procedures and Performance-Based Approach on Modern Unreinforced Masonry Buildings with Structural Irregularity." Buildings 11, no. 4: 147.
Among heritage buildings, masonry churches are complex structures often characterized by an open plan layout with slender perimeter walls. Their vulnerability to earthquakes is frequently increased by the absence of adequate connections between the various parts of the structural complex, together with the presence of thrusting horizontal elements such as masonry vaults and timber roofs. In this paper, the vulnerability and the seismic risk of thirteen masonry churches located in Tuscany (Italy) have been analysed with simplified methods to establish a first screening of the risk of this heritage typology. The methods are that proposed by Lourenço and Roque in 2006 and the so-called first level of analysis (LA-1), introduced by the Italian code. For one of these churches, the Basilica of San Francesco in Arezzo, the analyses of second (LA-2) and third (LA-3) level have been also performed according to the same code. The results highlight the contribution of the simplified approaches to establish a first selection of the priorities for subsequent investigations and, if needed, proper interventions. Approximately one-half of the churches composing the sample have the normalized simplified indexes lower than one, indicating the need of further investigations. For the Basilica of San Francesco the results of LA-2 level of analysis confirm the conclusions obtained with the more simplified procedures, while a criticism is highlighted with the LA-3 approach when the N2 method is adopted in combination with a pushover methodology of analysis.
Michele Betti; Luciano Galano; Paulo B. Lourenço. Territorial seismic risk assessment of a sample of 13 masonry churches in Tuscany (Italy) through simplified indexes. Engineering Structures 2021, 111479 .
AMA StyleMichele Betti, Luciano Galano, Paulo B. Lourenço. Territorial seismic risk assessment of a sample of 13 masonry churches in Tuscany (Italy) through simplified indexes. Engineering Structures. 2021; ():111479.
Chicago/Turabian StyleMichele Betti; Luciano Galano; Paulo B. Lourenço. 2021. "Territorial seismic risk assessment of a sample of 13 masonry churches in Tuscany (Italy) through simplified indexes." Engineering Structures , no. : 111479.
In the context of the structural safety evaluation of masonry arches under both gravitational and seismic loads, this study analyses the possibility to apply fast-assessment methodologies, aimed at defining intervention priorities through the proposal of typological abacuses. With this aim, two automatic VBA (Visual Basic for Application) procedures have been implemented and adopted to estimate the capacity of six configurations (from semi-circular to pointed) of stand-alone masonry arches to withstand vertical loads, and to calculate the horizontal load multiplier, related to the in-plane seismic capacity. The developed subroutines are based on the Uniqueness Theorem of Limit Analysis, so that a static and a kinematic approach have been adopted, respectively, for the estimation of the maximum vertical load, compatible with the geometric features, and the evaluation of the horizontal capacity. Subsequently, both procedures have been applied to a wide range of arches by means of a parametric study. The results thus obtained allow the definition of typological abacuses for the preliminary safety assessment of the investigated structural types.
Mattia Zizi; Daniela Cacace; Jafar Rouhi; Paulo B. Lourenço; Gianfranco De Matteis. Automatic Procedures for the Safety Assessment of Stand-alone Masonry Arches. International Journal of Architectural Heritage 2021, 1 -19.
AMA StyleMattia Zizi, Daniela Cacace, Jafar Rouhi, Paulo B. Lourenço, Gianfranco De Matteis. Automatic Procedures for the Safety Assessment of Stand-alone Masonry Arches. International Journal of Architectural Heritage. 2021; ():1-19.
Chicago/Turabian StyleMattia Zizi; Daniela Cacace; Jafar Rouhi; Paulo B. Lourenço; Gianfranco De Matteis. 2021. "Automatic Procedures for the Safety Assessment of Stand-alone Masonry Arches." International Journal of Architectural Heritage , no. : 1-19.
A severe earthquake hit Zagreb on the March 22, 2020 (magnitude ML = 5.5, with an epicenter 7 km north of the city center). During the COVID-19 lockdown, the event occurred and caused significant damage to the built environment and enormous disruption in everyday life. Brief facts about the Zagreb earthquake, the typology of buildings in the city, and the data collection after the quake itself are described. The paper focuses on post-earthquake assessment, damage classification, and failure patterns of residential buildings in Zagreb's old historical town, where masonry structures prevail. The earthquake critically damaged buildings that are important architectural achievements and ruptured Zagreb's historically recognizable city center. Furthermore, the data collected in the rapid post-earthquake assessment were analyzed and discussed. Graphical representations of damages are detailed and accompanied by photographs. This earthquake exposed Croatian building stock's vulnerability that should be mitigated as efficiently as possible in the coming years.
Mislav Stepinac; Paulo B. Lourenço; Josip Atalić; Tomislav Kišiček; Mario Uroš; Maja Baniček; Marta Šavor Novak. Damage classification of residential buildings in historical downtown after the ML5.5 earthquake in Zagreb, Croatia in 2020. International Journal of Disaster Risk Reduction 2021, 56, 102140 .
AMA StyleMislav Stepinac, Paulo B. Lourenço, Josip Atalić, Tomislav Kišiček, Mario Uroš, Maja Baniček, Marta Šavor Novak. Damage classification of residential buildings in historical downtown after the ML5.5 earthquake in Zagreb, Croatia in 2020. International Journal of Disaster Risk Reduction. 2021; 56 ():102140.
Chicago/Turabian StyleMislav Stepinac; Paulo B. Lourenço; Josip Atalić; Tomislav Kišiček; Mario Uroš; Maja Baniček; Marta Šavor Novak. 2021. "Damage classification of residential buildings in historical downtown after the ML5.5 earthquake in Zagreb, Croatia in 2020." International Journal of Disaster Risk Reduction 56, no. : 102140.
The country of Peru has a rich tradition of historic earthen structures from ancient archaeological sites to vernacular and monumental architectures. Nowadays, still a relevant part of the world population lives in earthen houses, which are found to be quite vulnerable to horizontal loading causing considerable loss of life over time. Hence, the importance of studying the seismic performance of these buildings to predict their capacity and failure mechanisms. After the destruction caused by the 2007 Pisco earthquake, the Getty Conservation Institute initiated a project to better understand the seismic performance of four historic earthen building typologies present in Peru. This paper addresses the seismic assessment of Casa Arones, which is considered as a prototype of the typology of large vernacular houses present in many historical centers of the Andean Region of Peru. Advanced numerical analysis is used to assess the global behaviour of the building, and to identify the damage distribution and failure mechanisms. The challenges faced in the study, related to the complexity of the structure and the insufficient information on its morphology and materials properties, are discussed. Moreover, sensitivity analysis is used to understand the influence of floors and roof on the global behaviour, which is a novel contribution.
Federica Greco; Paulo B. Lourenço. Seismic assessment of large historic vernacular adobe buildings in the Andean Region of Peru. Learning from Casa Arones in cusco. Journal of Building Engineering 2021, 40, 102341 .
AMA StyleFederica Greco, Paulo B. Lourenço. Seismic assessment of large historic vernacular adobe buildings in the Andean Region of Peru. Learning from Casa Arones in cusco. Journal of Building Engineering. 2021; 40 ():102341.
Chicago/Turabian StyleFederica Greco; Paulo B. Lourenço. 2021. "Seismic assessment of large historic vernacular adobe buildings in the Andean Region of Peru. Learning from Casa Arones in cusco." Journal of Building Engineering 40, no. : 102341.
The seismic behaviour of reinforced concrete (RC) structures is critically influenced by the complex mechanical interactions at beam-column joints. To ensure the desired hierarchy of failure is achieved when retrofitting existing structures, numerical and experimental assessments need to represent realistic structures. A review of published literature indicates that most experimental work on the seismic behaviour pre-1970′s RC beam-column connections considers sub-assemblies without slabs or transverse beams, which are unrepresentative of reality. To evaluate the effect of these elements on the failure mechanism, retrofit need and retrofit effectiveness, experiments on four full-scale beam-column joints are carried out. Two specimens with and without slab and transverse beams, are tested in their as-built and FRP strengthened configurations. As expected, the experimental results demonstrate that the progression of damage and failure mechanisms differ significantly when slabs and transverse beams are present, confirming previous numerical and experimental evidence on the strong contribution of these elements on the overall joint behaviour. Moreover, a significantly higher retrofit effectiveness is observed for the specimen without slab and transverse beam. This implies that experiments on retrofitted joints without slab and transverse beam can lead to a focus on joint shear strengthening alone as they inadequately represent the hierarchy of strengths of the framing members. They can also lead to an overestimation of retrofit effectiveness. These observations have implications when considering common simplifying assumptions made in the numerical modelling of RC moment resisting frames when assessing their seismic performance.
Daniel A. Pohoryles; Jose Melo; Tiziana Rossetto; Humberto Varum; Dina D'Ayala. Effect of slab and transverse beam on the FRP retrofit effectiveness for existing reinforced concrete structures under seismic loading. Engineering Structures 2021, 234, 111991 .
AMA StyleDaniel A. Pohoryles, Jose Melo, Tiziana Rossetto, Humberto Varum, Dina D'Ayala. Effect of slab and transverse beam on the FRP retrofit effectiveness for existing reinforced concrete structures under seismic loading. Engineering Structures. 2021; 234 ():111991.
Chicago/Turabian StyleDaniel A. Pohoryles; Jose Melo; Tiziana Rossetto; Humberto Varum; Dina D'Ayala. 2021. "Effect of slab and transverse beam on the FRP retrofit effectiveness for existing reinforced concrete structures under seismic loading." Engineering Structures 234, no. : 111991.