Engineering Structures最新文献

Inerter-based dissipation for vibration control of a cable-stayed bridge subjected to transverse seismic excitation

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-04-26 DOI: 10.1016/j.engstruct.2025.120297

Matteo Mazzeo, Roberta Santoro, Silvia Sciutteri, Giuseppe Ricciardi

Cable-stayed bridges are an effective solution for infrastructural connection due to their long-spanning capacity and slenderness. However, in the most common deck-tower floating configuration, such structures are prone to be damaged under strong seismic excitation due to excessive transverse displacement demand and possible pounding between the towers and the deck. This paper addresses the transverse vibration control problem in cable-stayed bridges subjected to seismic excitation by exploiting Inerter-Based Dissipators (IBDs). Specifically, a simplified four degrees-of-freedom dynamic model of a cable-stayed bridge prototype is introduced to describe its transverse response, considering the effect of different configurations of IBDs in the equation of motion. The design of such devices is performed using an optimization approach, the presence of the earthquake is simulated describing the seismic acceleration as a filtered Gaussian stochastic process and the damper nonlinearities are addressed via the Stochastic Linearization Technique. A comparative analysis is carried out for a bridge in terms of transverse displacement control considering a proposed IBD configuration and comparing its performance with other IBDs systems and conventional viscous dampers. It is shown that the proposed IBD configuration achieves a superior transverse vibration control performance compared to the other inerter-based devices considered, regardless of the selected level of inertance or the band-type excitation, with significant tower-deck relative displacement reductions as well as shear force and bending moment at the tower base.

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引用次数: 0

Prediction of ultimate strength of FRP confined steel reinforced concrete columns subjected to eccentric compression loads

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-04-26 DOI: 10.1016/j.engstruct.2025.120334

Dan Wang , Jin-Ben Gu , Yi Tao , Qing-Xuan Shi

Understanding the mechanical behavior of FRP confined steel reinforced concrete (FCSRC) columns under eccentric loads provides a theoretical support for optimizing its structural performance subjected to complex load conditions. This study was dedicated to developing a new strength model to predict the ultimate load capacity of FCSRC columns under eccentric compression loads. The proposed model introduced the unified strength theory as a framework, meanwhile accounted for the effect of effective steel flange width and combined confinement from Fiber Reinforced Polymer (FRP) tube and steel section. The applicability of the strength model was estimated by comparing it with available test results under the same load conditions. The results showed that this model provided a favorable prediction for ultimate eccentric compression loads of FCSRC columns with different concrete strengths, consistent with the experimental findings. Also, it can give a better estimation of the load capacity of FCSRC columns suffering from concentric compression loads.

引用次数: 0

Fatigue shear failure mechanism and prediction method for UHPC-NC bond interfaces

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-04-26 DOI: 10.1016/j.engstruct.2025.120455

Huaqian Zhong , Zhiliang Chen , Changxi Liu , Shaohua He , Zhiyong Wan , Zhitao Yu

This paper explores the fatigue failure mechanism and prediction methods for the bonded interface between ultra-high performance concrete (UHPC) and normal concrete (NC) under shear loading, featuring an experimental program that includes two sets of direct shear tests on a total of 19 Z-shaped UHPC-NC combined specimens. The first set consists of eight static shear tests, from the authors’ previous study. The second includes the eleven fatigue shear tests, key aspects explored include fatigue failure modes, residual shear strength, stiffness degradation, and fatigue life of the UHPC-NC interface, considering different bond sizes, load amplitudes, and pre-existing defects (e.g., 0 %, 15 %, and 30 %). Experimental results indicate that interfaces with preset bond defects are more susceptible to fatigue shear damage due to stress concentrations, with fatigue life decreasing as defect dimension increases. Damage accumulates at the UHPC-NC interface with additional loading cycles, leading to persistent slippage and reduced bonding strength. The results also reveal that the fatigue residual bond between UHPC and NC decline as interfacial size increases. A semi-empirical model, combining static shear calculation with non-linear cumulative damage method, was developed to predict the UHPC-NC interface’s residual bond strength and validated against experimental results. This research provides valuable experimental data and theoretical insights for enhancing the fatigue design of shear bonds at UHPC-NC interfaces.

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引用次数: 0

Experimental testing of school furniture designed with life-saving functions in case of earthquakes

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-04-26 DOI: 10.1016/j.engstruct.2025.120389

Martina Sciomenta , Gabriele Tamagnone , Laura Gioiella , Fabio Micozzi , Alessandro Zona , Andrea Dall’Asta , Massimo Fragiacomo

This study explores newly developed furniture working as protective elements in the case of seismic events causing damage in buildings. Attention is given to a school classroom where desks and shelving units are the typical furniture adopted. School desks aim to protect against falling ceiling debris, while shelving units are intended to prevent damage to and overturning of partition walls. Previous designs for desks were costly and impractical, whereas shelving units received minimal attention beyond stronger wall connections to partition walls that, however, might be critical during earthquakes, as they can sustain early damage, posing risks even during moderate seismic events. The article outlines the initial structural concepts, preliminary analyses, full-scale prototypes, and experimental tests under extreme conditions. Differently from other proposals that can be found browsing internet, the solutions illustrated and tested in this study use elements of dimensions similar or even smaller to those of traditional school furniture, resulting in weights and costs that are comparable to current industrial productions in the market. The results from this study are expected to provide a novel perspective and design approach for school furniture design in seismic zones, contributing to the broader field of disaster risk reduction and resilience planning in educational environments.

{"title":"Experimental testing of school furniture designed with life-saving functions in case of earthquakes","authors":"Martina Sciomenta , Gabriele Tamagnone , Laura Gioiella , Fabio Micozzi , Alessandro Zona , Andrea Dall’Asta , Massimo Fragiacomo","doi":"10.1016/j.engstruct.2025.120389","DOIUrl":"10.1016/j.engstruct.2025.120389","url":null,"abstract":"<div><div>This study explores newly developed furniture working as protective elements in the case of seismic events causing damage in buildings. Attention is given to a school classroom where desks and shelving units are the typical furniture adopted. School desks aim to protect against falling ceiling debris, while shelving units are intended to prevent damage to and overturning of partition walls. Previous designs for desks were costly and impractical, whereas shelving units received minimal attention beyond stronger wall connections to partition walls that, however, might be critical during earthquakes, as they can sustain early damage, posing risks even during moderate seismic events. The article outlines the initial structural concepts, preliminary analyses, full-scale prototypes, and experimental tests under extreme conditions. Differently from other proposals that can be found browsing internet, the solutions illustrated and tested in this study use elements of dimensions similar or even smaller to those of traditional school furniture, resulting in weights and costs that are comparable to current industrial productions in the market. The results from this study are expected to provide a novel perspective and design approach for school furniture design in seismic zones, contributing to the broader field of disaster risk reduction and resilience planning in educational environments.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"336 ","pages":"Article 120389"},"PeriodicalIF":5.6,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ultra-high performance rubberised concrete slabs cast in stay-in-place formworks: Enhancing shear strength and vibration characteristics

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-04-26 DOI: 10.1016/j.engstruct.2025.120322

Vu To-Anh Phan , Hoyeol Hur , Peter McUtchen , Emad Pournasiri , Tung M. Tran , Thong M. Pham

This study investigated innovative bridge slabs using ultra-high-performance rubberized concrete (UHPRuC) combined with special square hollow stiffeners (SHS) or Y-shaped stiffeners. The newly developed UHPRuC was prepared using crumb rubber, silica sand, hooked-end steel fibers, cement, silica fume, and superplasticizer. Four slabs were prepared: two measuring 1400 mm× 600 mm x 75 mm without glass fiber-reinforced polymer (GFRP) SIP formwork, and another two measuring 1400 mm× 600 mm x 65 mm with GFRP SIP formwork. The results showed that incorporating 20 % crumb rubber into UHPRuC increased the damping ratio by 1.5 times and the maximum strain by 3.5 times compared to reference slab. Furthermore, the Y-shaped stiffener significantly enhanced the ultimate loading capacity and resistance to shear stress, and the UHPRuC slabs cast on GFRP SIP formwork demonstrated a 60–91 % improvement over normal-strength concrete slabs. Slabs without GFRP SIP formwork experienced a flexural-shear failure, while slabs with GFRP SIP formwork exhibited predominantly shear failure. Finally, a comparison between experimental data and theoretical predictions revealed that the punching shear strength of the SHS slab closely matched the experimental results, with a 4 % difference. However, the Y-stiffened slab exhibited an experimental value that was 44 % higher than predicted.

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引用次数: 0

Structural design and performance of a steel joint for driven precast concrete energy piles

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-04-26 DOI: 10.1016/j.engstruct.2025.120256

Habibollah Sadeghi , Jukka Haavisto , Teemu Tupala , Anssi Laaksonen , Rao Martand Singh

Geothermal energy piles are deep foundations primarily used to transfer building loads down to competent ground layers, while they can be used as a heating and cooling source/sink for buildings. Most energy pile foundations are cast-in-place piles, while precast concrete driven energy piles (DEPs) have not been utilized due to the lack of a suitable joint to connect pile segments. This study presents a detailed structural design and performance of a novel steel joint for precast concrete DEPs. Firstly, the two most common joint sizes are designed based on the finite element method, and the dimensions and steel grades of the joint are presented. Secondly, the casting procedure of energy piles using the newly designed joint is explained in detail. Thirdly, the impact and bending tests performed according to the standards are presented, the standard procedures are critically evaluated, and recommendations are provided. The impact test results show that both joint sizes remained undamaged after being subjected to 1000 blows, imposing a minimum of 28 MPa of stress. The small and large sizes of joints have a flexural stiffness (EI) of 3500 kN.m² and 7720 kN.m², respectively, according to the standard flexural tests. Lastly, the flexural stiffness distribution of the pile and joints is measured using digital image correlation (DIC) and compared with the current method recommended by the standard. The current standard requirements measure flexural stiffness based on point sensor measurements, and the distribution of flexural stiffness along the pile and joint is not evaluated. Standard stiffness is affected by the concrete and reinforcements in the pile; however, there is no standard requirement for the type/grade of the concrete and reinforcements used for manufacturing the test specimens.

{"title":"Structural design and performance of a steel joint for driven precast concrete energy piles","authors":"Habibollah Sadeghi , Jukka Haavisto , Teemu Tupala , Anssi Laaksonen , Rao Martand Singh","doi":"10.1016/j.engstruct.2025.120256","DOIUrl":"10.1016/j.engstruct.2025.120256","url":null,"abstract":"<div><div>Geothermal energy piles are deep foundations primarily used to transfer building loads down to competent ground layers, while they can be used as a heating and cooling source/sink for buildings. Most energy pile foundations are cast-in-place piles, while precast concrete driven energy piles (DEPs) have not been utilized due to the lack of a suitable joint to connect pile segments. This study presents a detailed structural design and performance of a novel steel joint for precast concrete DEPs. Firstly, the two most common joint sizes are designed based on the finite element method, and the dimensions and steel grades of the joint are presented. Secondly, the casting procedure of energy piles using the newly designed joint is explained in detail. Thirdly, the impact and bending tests performed according to the standards are presented, the standard procedures are critically evaluated, and recommendations are provided. The impact test results show that both joint sizes remained undamaged after being subjected to 1000 blows, imposing a minimum of 28 MPa of stress. The small and large sizes of joints have a flexural stiffness (EI) of 3500 kN.m<sup>2</sup> and 7720 kN.m<sup>2</sup>, respectively, according to the standard flexural tests. Lastly, the flexural stiffness distribution of the pile and joints is measured using digital image correlation (DIC) and compared with the current method recommended by the standard. The current standard requirements measure flexural stiffness based on point sensor measurements, and the distribution of flexural stiffness along the pile and joint is not evaluated. Standard stiffness is affected by the concrete and reinforcements in the pile; however, there is no standard requirement for the type/grade of the concrete and reinforcements used for manufacturing the test specimens.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"336 ","pages":"Article 120256"},"PeriodicalIF":5.6,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental and theoretical investigation on the dynamic response of foam-geopolymer sandwich cylindrical structure under long-duration plane load

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-04-26 DOI: 10.1016/j.engstruct.2025.120407

Hang Zhou , Zhen Wang , Haoxiang Chen , Wenxin Wang , Dongming Yan , Kangbo Zhao , Yong He

In this study, the dynamic response of the foam-geopolymer sandwich cylindrical structures (FSCS) under long-duration plane shock wave loading and the energy absorption properties of the foam-geopolymer cushion layer were investigated through model-scale blast-resistant experiments and theoretical calculations. Five FSCS models with different cushion layer thicknesses and densities were tested in a large-scale enclosed blast-resistant device. The results found that the FSCS models remained undamaged when subjected to long-duration plane wave loading with a peak pressure of 0.6 MPa and a duration of 200 ms. Increasing the cushion layer thickness enhanced pressure attenuation from 65.31 % at 15 mm to 75.71 % at 25 mm, while lower-density foam-geopolymer materials exhibited better attenuation, reaching 80.59 % at 579 kg/m³ compared to 66.36 % at 1166 kg/m³ . The top of the cylinder experienced pressure four times higher than the lateral center, with peak displacement and acceleration amplitude increasing by 60 % and 90 %, respectively. Circumferential strain was more pronounced than axial strain, while the inner wall of the lining primarily underwent elastic deformation. Furthermore, a dynamic mechanical model for underground circular tunnels under long-duration planar loading was developed, incorporating an optimal cushion layer thickness calculation method that considers material self-weight and impedance effects. This model accurately predicts the deflection variation of underground sandwich cylindrical structures at any time, providing crucial insights for the design and optimization of cushion energy-absorbing layers in sandwich structures.

{"title":"Experimental and theoretical investigation on the dynamic response of foam-geopolymer sandwich cylindrical structure under long-duration plane load","authors":"Hang Zhou , Zhen Wang , Haoxiang Chen , Wenxin Wang , Dongming Yan , Kangbo Zhao , Yong He","doi":"10.1016/j.engstruct.2025.120407","DOIUrl":"10.1016/j.engstruct.2025.120407","url":null,"abstract":"<div><div>In this study, the dynamic response of the foam-geopolymer sandwich cylindrical structures (FSCS) under long-duration plane shock wave loading and the energy absorption properties of the foam-geopolymer cushion layer were investigated through model-scale blast-resistant experiments and theoretical calculations. Five FSCS models with different cushion layer thicknesses and densities were tested in a large-scale enclosed blast-resistant device. The results found that the FSCS models remained undamaged when subjected to long-duration plane wave loading with a peak pressure of 0.6 MPa and a duration of 200 ms. Increasing the cushion layer thickness enhanced pressure attenuation from 65.31 % at 15 mm to 75.71 % at 25 mm, while lower-density foam-geopolymer materials exhibited better attenuation, reaching 80.59 % at 579 kg/m³ compared to 66.36 % at 1166 kg/m³ . The top of the cylinder experienced pressure four times higher than the lateral center, with peak displacement and acceleration amplitude increasing by 60 % and 90 %, respectively. Circumferential strain was more pronounced than axial strain, while the inner wall of the lining primarily underwent elastic deformation. Furthermore, a dynamic mechanical model for underground circular tunnels under long-duration planar loading was developed, incorporating an optimal cushion layer thickness calculation method that considers material self-weight and impedance effects. This model accurately predicts the deflection variation of underground sandwich cylindrical structures at any time, providing crucial insights for the design and optimization of cushion energy-absorbing layers in sandwich structures.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"336 ","pages":"Article 120407"},"PeriodicalIF":5.6,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Static strength of stainless-clad bimetallic steel CHS T- and K-joints

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-04-26 DOI: 10.1016/j.engstruct.2025.120405

Yi Yang , Fei Gao , Junbo Chen , Tak-Ming Chan

This paper presents an experimental investigation into the structural behaviour and strength of stainless-clad (SC) bimetallic steel circular hollow section (CHS) T- and gapped K-joints. The SCCHS joints consisted of chord and brace members made up of SC bimetallic steel tubes, which were cold-formed from SC bimetallic steel plates with nominal thicknesses of 8 mm, composed of 2 mm 304 L cladding stainless steel and 6 mm Q235 substrate carbon steel. A total of eight SCCHS joints, including four T-joints and four K-joints, were tested. For the T-joints, the axial loading was applied at the brace members, while the axial loading was applied at the chord members for K-joints. In the experimental programme, the brace to chord diameter ratio β ranged from 0.56 to 0.75, the chord diameter to thickness ratio 2γ varied from 25.00 to 33.25, and the gap distance between two braces to chord diameter ratio g/d₀ of K-joints changed from 0.139 to 0.408. The load-deformation curves, joint strengths, as well as failure modes of the SCCHS T- and K-joints have been presented. The test results of SCCHS T- and K-joints demonstrated similar failure modes and joint strengths to those of carbon steel joints reported in the literature. Finally, the test results have been used to evaluate the applicability of current design recommendations for normal strength steel joints in ANSI/AISC 360–22, EN 1993–1–8 and API 2A-LRFD to the design of SCCHS T- and K-joints. Results indicate that the ANSI/AISC 360–22, EN 1993–1–8 and API 2A-LRFD characteristic strength equations are conservative for the design of SCCHS T-joints under axial brace load. The ANSI/AISC 360–22 characteristic strength equations tend to underestimate the SCCHS K-joint strengths, while those specified in EN 1993–1–8 and API 2A-LRFD produce marginal predictions to the test joint strengths.

{"title":"Static strength of stainless-clad bimetallic steel CHS T- and K-joints","authors":"Yi Yang , Fei Gao , Junbo Chen , Tak-Ming Chan","doi":"10.1016/j.engstruct.2025.120405","DOIUrl":"10.1016/j.engstruct.2025.120405","url":null,"abstract":"<div><div>This paper presents an experimental investigation into the structural behaviour and strength of stainless-clad (SC) bimetallic steel circular hollow section (CHS) T- and gapped K-joints. The SCCHS joints consisted of chord and brace members made up of SC bimetallic steel tubes, which were cold-formed from SC bimetallic steel plates with nominal thicknesses of 8 mm, composed of 2 mm 304 L cladding stainless steel and 6 mm Q235 substrate carbon steel. A total of eight SCCHS joints, including four T-joints and four K-joints, were tested. For the T-joints, the axial loading was applied at the brace members, while the axial loading was applied at the chord members for K-joints. In the experimental programme, the brace to chord diameter ratio <em>β</em> ranged from 0.56 to 0.75, the chord diameter to thickness ratio 2<em>γ</em> varied from 25.00 to 33.25, and the gap distance between two braces to chord diameter ratio <em>g</em>/<em>d</em><sub>0</sub> of K-joints changed from 0.139 to 0.408. The load-deformation curves, joint strengths, as well as failure modes of the SCCHS T- and K-joints have been presented. The test results of SCCHS T- and K-joints demonstrated similar failure modes and joint strengths to those of carbon steel joints reported in the literature. Finally, the test results have been used to evaluate the applicability of current design recommendations for normal strength steel joints in ANSI/AISC 360–22, EN 1993–1–8 and API 2A-LRFD to the design of SCCHS T- and K-joints. Results indicate that the ANSI/AISC 360–22, EN 1993–1–8 and API 2A-LRFD characteristic strength equations are conservative for the design of SCCHS T-joints under axial brace load. The ANSI/AISC 360–22 characteristic strength equations tend to underestimate the SCCHS K-joint strengths, while those specified in EN 1993–1–8 and API 2A-LRFD produce marginal predictions to the test joint strengths.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"336 ","pages":"Article 120405"},"PeriodicalIF":5.6,"publicationDate":"2025-04-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143874811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Performance-based seismic design method of stacked modular steel building based on three-dimensional seismic isolation

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-04-26 DOI: 10.1016/j.engstruct.2025.120438

Ze Mo , Binglin Lai , Ganping Shu , Peng Chen , T.Y. Yang

Stacked modular steel building (SMSB) is widely used in China due to their rapid assembly, cost-effectiveness, and environmental benefits. However, their seismic performance is often poor due to discontinuous structural configurations. Seismic isolation technology, particularly the air spring-lead rubber bearing (AS-LRB) developed by the authors, offers a promising solution to enhance SMSB resilience. Despite its potential, the application of AS-LRB is limited by the lack of a systematic calculation method for performance parameters and a performance-based seismic design (PBSD) framework for SMSB. In this study, the construction and performance of the AS-LRB are briefly introduced, a calculation method for determining its performance parameters is derived, and a PBSD method for SMSBs based on the AS-LRB seismic isolation device is proposed in conjunction with the Chinese standard (GB/T 51408–2021), which mainly considers target period ratio (TPR) and design transmission ratio (DTR). To verify the effectiveness of the PBSD method, a four-story, three-span SMSB was designed using the PBSD method with AS-LRB, the isolation performance of SMSB was analyzed, and several calculations were performed to determine the TPR and DTR under different seismic performance objective (SPO). Results indicate that the calculation method can accurately obtain the performance parameters of the AS-LRB, the PBSD method based on AS-LRB for SMSB can achieve the expected SPO, and the isolated SMSB exhibits a better isolation effect. Furthermore, TPR and DTR with different SPO were obtained to provide reference values for the design of SMSB.

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引用次数: 0

Unified design-oriented model for the shear strengthening of masonry walls with Inorganic Mortar Composite systems

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-04-24 DOI: 10.1016/j.engstruct.2025.120394

Silvia Calò , Alessio Cascardi , Maria Antonietta Aiello

Masonry structures may exhibit fragile behavior in seismic-prone zones. In fact, most of the energy dissipation is achieved by means of shear cracking. Consequently, in-plane retrofitting is recommended. Among the different techniques, the use of Inorganic Mortar Composite (IMC) systems is nowadays under the magnifying glass due to the appreciable advantages related to the mechanical and chemical compatibility with existing masonry substrates and, at the same time, to the possible removability of the intervention itself. Nonetheless, the available design formulae are often inadequate for predicting the additional strength provided by the dry fabric-based systems (namely Fabric Reinforced Cementitious Matrix/Mortar – FRCM) because of the plurality of options in the side-by-side placing the masonry, mortar-matrix and the reinforcement (i.e. fiber mesh/fabric). The main lacks consist in neglecting the specific contribution of the FRCM-matrix, as well as the matrix-to-fabric bond interaction. Furthermore, in case of pre-impregnated fabric (namely Composite Reinforced Mortar – CRM), an analytical model is currently missed in design Codes. In the light of this, the present paper aims to propose a novel empirical set of equations (for both FRCM and CRM cases) based on large and critical data collection, clustering, cleaning, and processing. The goal is to meet high accuracy of the foreseen using simple formulations in the perspective of design Code targeted to practitioners. Innovation is stated in providing a unified approach - first - able to account both countable (i.e. geometrical and mechanical properties of the substrate and the strengthening) and categorical (i.e. type of IMC-system, use of connectors and symmetry/asymmetry of the strengthening) variables - second. In such a way, an exploitation ratio of the matrix-to-fabric bond interaction is proposed and validated for both the FRCM- and CRM-systems. Lastly, the theoretical versus experimental comparison, associated with parametric analysis, demonstrated the reliability of the proposal, as well as the improved accuracy against other existing models.

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引用次数: 0