Engineering Structures最新文献_第6页

Probabilistic resilience assessment of structures considering the functional uncertainty: A case study for external prestressed subframe in strengthening

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-03-09 DOI: 10.1016/j.engstruct.2025.119968

Xu-Yang Cao , De-Cheng Feng

Seismic resilience is a critical index in the earthquake engineering. In recent years, it has received extensive attention and has been broadly used in post-earthquake assessments, especially for the structures after strengthening. At this stage, the seismic resilience is commonly analyzed using deterministic approaches, while the corresponding probabilistic resilience assessment still needs further research. In this paper, a probabilistic resilience assessment framework of structures considering the functional uncertainty is proposed, and a case study for external prestressed subframe in seismic strengthening is performed. The probabilistic resilience assessment framework consists of the probabilistic analyses of fragility, expected loss, residual functionality, recovery time and resilience index, and the resilience developments along with the intensity level or recovery time are detailedly discussed in the procedure. Subsequently, an implementary example of the existing frame strengthened by an external prestressed subframe is given, and the proposed probabilistic resilience assessment framework is performed for comprehensive analyses. In general, the functionality varying with recovery time presents significant uncertainty for each scenario and intensity level, which proves the necessity of resilience analyses in a probabilistic way. With the increase of prestress level, the obtained mean resilience index increases, and the resilience exceeding probability curves move upward for all the conditions, which signifies the superiority of a higher prestress level to increase the seismic resilience and to improve the risk-resistant capacity in external strengthening. In a sense, the probabilistic resilience assessment framework evaluates the resilience development from an uncertain perspective, which provides a significant reference for the subsequent probabilistic risk analyses in engineering structures.

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引用次数: 0

Global buckling prevention of multi-celled corrugated-plate CFST walls under pure in-plane bending loads

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-03-09 DOI: 10.1016/j.engstruct.2025.120061

Jia-Ming Zhang, Gen-Shu Tong, Jing-Zhong Tong

The multi-celled corrugated-plate concrete-filled steel tubular (MC-CFST) wall system is a novel structural solution featuring an alternating arrangement of corrugated cells and interval elements. This design offers high flexibility and is well-suited for prefabricated construction. Horizontally placed corrugated steel plates provide excellent confinement for the infilled concrete, significantly reducing steel consumption and wall thickness. This study systematically investigated the stability performance of MC-CFST walls under pure in-plane bending loads through theoretical analysis and numerical simulations. Based on the theory of thin-walled elastic structures, formulas for torsional and warping rigidities were derived, along with a theoretical formula for calculating the critical moment. A refined finite element (FE) model was developed to simulate the global flexural-torsional buckling behavior of MC-CFST walls and was validated against the theoretical formulas. The model was further used to analyze failure modes during elastic and elastoplastic stages and to assess the effects of wall height and width on stability performance. The results revealed that as wall height and width increase, the failure mode transitions from strength-controlled to stability-controlled. When the normalized slenderness ratio does not exceed 0.4, the composite wall is unlikely to experience global flexural-torsional buckling. However, comparisons showed that existing design codes fail to provide conservative predictions of the stability performance of MC-CFST walls under pure in-plane bending loads. Therefore, a new stability design curve was proposed and proved to be capable of providing design results with reasonable accuracy and safety margin, demonstrating its validity for practical designs of MC-CFST walls.

{"title":"Global buckling prevention of multi-celled corrugated-plate CFST walls under pure in-plane bending loads","authors":"Jia-Ming Zhang, Gen-Shu Tong, Jing-Zhong Tong","doi":"10.1016/j.engstruct.2025.120061","DOIUrl":"10.1016/j.engstruct.2025.120061","url":null,"abstract":"<div><div>The multi-celled corrugated-plate concrete-filled steel tubular (MC-CFST) wall system is a novel structural solution featuring an alternating arrangement of corrugated cells and interval elements. This design offers high flexibility and is well-suited for prefabricated construction. Horizontally placed corrugated steel plates provide excellent confinement for the infilled concrete, significantly reducing steel consumption and wall thickness. This study systematically investigated the stability performance of MC-CFST walls under pure in-plane bending loads through theoretical analysis and numerical simulations. Based on the theory of thin-walled elastic structures, formulas for torsional and warping rigidities were derived, along with a theoretical formula for calculating the critical moment. A refined finite element (FE) model was developed to simulate the global flexural-torsional buckling behavior of MC-CFST walls and was validated against the theoretical formulas. The model was further used to analyze failure modes during elastic and elastoplastic stages and to assess the effects of wall height and width on stability performance. The results revealed that as wall height and width increase, the failure mode transitions from strength-controlled to stability-controlled. When the normalized slenderness ratio does not exceed 0.4, the composite wall is unlikely to experience global flexural-torsional buckling. However, comparisons showed that existing design codes fail to provide conservative predictions of the stability performance of MC-CFST walls under pure in-plane bending loads. Therefore, a new stability design curve was proposed and proved to be capable of providing design results with reasonable accuracy and safety margin, demonstrating its validity for practical designs of MC-CFST walls.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"332 ","pages":"Article 120061"},"PeriodicalIF":5.6,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143580776","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

A scaling law for fire duration in RC frames to resist fire-induced progressive collapse: Considering critical design parameters

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-03-09 DOI: 10.1016/j.engstruct.2025.120099

Dongqiu Lan , Liu Jin , Yaowen Yang , Renbo Zhang , Jian Li , Kai Qian

Fire is a significant factor that can lead to progressive collapse in structures. Due to spatial limitations, scaled models are often employed in collapse experiments. However, traditional similarity laws for fire testing require scaled models to experience heating rates much higher than those of the prototype, which is difficult to achieve with standard fire furnaces. This study addresses this challenge by conducting numerical analyses on geometrically scaled reinforced RC beam-column structures. A unified similarity law for fire duration is proposed, incorporating key design parameters such as span-depth ratio, reinforcement ratio, and concrete cover thickness. This law enables scaled models to replicate progressive collapse behavior of RC prototype frames. The results reveal that similar mechanical performance can be achieved when rebar and average beam-section temperatures are comparable, despite variations in internal concrete temperatures. Additionally, smaller span-depth ratios cause more severe beam damage under fire exposure. Increasing span-depth ratios from 10 to 12 and 14 has minimal impact on load capacity at ambient temperature. However, smaller span-depth ratios result in higher ultimate load capacity after prolonged fire exposure. These findings provide a practical approach for scaling fire-induced collapse experiments and highlight the role of the key design parameters in determining structural performance under elevated temperatures.

{"title":"A scaling law for fire duration in RC frames to resist fire-induced progressive collapse: Considering critical design parameters","authors":"Dongqiu Lan , Liu Jin , Yaowen Yang , Renbo Zhang , Jian Li , Kai Qian","doi":"10.1016/j.engstruct.2025.120099","DOIUrl":"10.1016/j.engstruct.2025.120099","url":null,"abstract":"<div><div>Fire is a significant factor that can lead to progressive collapse in structures. Due to spatial limitations, scaled models are often employed in collapse experiments. However, traditional similarity laws for fire testing require scaled models to experience heating rates much higher than those of the prototype, which is difficult to achieve with standard fire furnaces. This study addresses this challenge by conducting numerical analyses on geometrically scaled reinforced RC beam-column structures. A unified similarity law for fire duration is proposed, incorporating key design parameters such as span-depth ratio, reinforcement ratio, and concrete cover thickness. This law enables scaled models to replicate progressive collapse behavior of RC prototype frames. The results reveal that similar mechanical performance can be achieved when rebar and average beam-section temperatures are comparable, despite variations in internal concrete temperatures. Additionally, smaller span-depth ratios cause more severe beam damage under fire exposure. Increasing span-depth ratios from 10 to 12 and 14 has minimal impact on load capacity at ambient temperature. However, smaller span-depth ratios result in higher ultimate load capacity after prolonged fire exposure. These findings provide a practical approach for scaling fire-induced collapse experiments and highlight the role of the key design parameters in determining structural performance under elevated temperatures.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"332 ","pages":"Article 120099"},"PeriodicalIF":5.6,"publicationDate":"2025-03-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143580849","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

Crushing response and multi-objective optimization of a novel double-feature bio-inspired gradient lattice structure under dynamic loading conditions

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-03-09 DOI: 10.1016/j.engstruct.2025.120088

Yahui Chang , Xiangqing Kong , Ning Zhang , Zewen Gu , Lu Jiang

To meet the impact requirements of lightweight lattice structure under varying orientations, inspired by the bidirectional gradient distribution characteristics of spider webs and the excellent impact resistance of the peacock mantis shrimp, a novel double-feature bio-inspired gradient lattice structure (DBGLS) was proposed in the study. By combining the bionic gradient structure with the bionic lattice structure, DBGLS can realize the synergistic mechanism of various bionic characteristics, enhancing impact resistance and energy absorption under multi-angle loads. A finite element simulation model for DBGLS is established, and 3D printing technique is utilized to manufacture test specimens for quasi-static compression tests to validate the simulation model’s accuracy. Afterwards, the stress distribution, deformation, load capacity, and energy absorption of DBGLS under multi-angle impact loading are systematically analyzed. Relying on the simulation results, response surface methodology (RSM) and second-generation non-dominated ranking genetic algorithm (NSGA-II) are applied to perform multi-objective optimization on DBGLS. The results indicate that the DBGLS outperforms the uniform and single gradient structures in bearing capacity and impact resistance under axial and oblique loads. Among them, the DBGLS with a negative lateral gradient and positive longitudinal gradient exhibits the highest specific energy absorption, 36.84 % higher than the uniform structure. The optimal design parameters of DBGLS are obtained through multi-objective optimization. The optimized DBGLS demonstrates a 40.07 % increase in specific energy absorption and a 24.90 % reduction in initial peak force compared to the original structure. This study provides new insights for designing bionic gradient lattice structures under complex loading conditions.

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引用次数: 0

Empirical and precise finite element modelling of bond-slip contact behavior between heat-damaged concrete and anchored CFRP composites with groove

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-03-09 DOI: 10.1016/j.engstruct.2025.120042

Rajai Z. Al-Rousan, Bara’a R. Alnemrawi

Predicting the overall capacity of Reinforced Concrete (RC) structures strengthened with Carbon Fiber Reinforced Polymers (CFRP) is challenging due to the difficulties in addressing their bond strength accurately. Concerns regarding the predicting accuracy are induced, including debonding probability, strengthening anchorage, and constituent material’s degradation due to sudden action such as exposure to high temperatures. This study presents a new bond-slip relationship for predicting the bond-slippage behavior of groove-anchored CFRP-strengthened members exposed to heat-damage effect using the nonlinear finite element analysis (NLFEA) method. The new model was generated using various high-temperature levels from 23° C to 800° C, CFRP bonded length (L_f) (0.1 L_c(length of the concrete specimen) to 1.0 L_c), CFRP bonded width (b_f) (0.1b_c(width of the concrete specimen) to 1.0b_c), and anchored groove numbers (0−3). The simulation was accomplished using ANSYS software and its accuracy was ensured using the precisely captured lateral strain values and overall distribution within the CFRP strips at the interface area. It was observed that normal and lateral stress contours were irregularly distributed within the CFRP strip width, whereas a regular distribution was captured in the other two directions. The new models were compared with experimental and theoretical models from the literature where high predictability was demonstrated compared to high disturbance and errors for the other existing models.

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引用次数: 0

Experimental study on the interfacial shear performance between macro basalt fibers reinforced UHPC as repair material and normal concrete

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-03-08 DOI: 10.1016/j.engstruct.2025.120044

Zhiyuan Chen , Xin Wang , Lining Ding , Kaidi Jiang , Fusheng Niu , Hua Wang , Zhishen Wu

The novel ultra high performance concrete (UHPC) reinforced with macro basalt fibers (MBFs), which has better performance of fiber distribution, electrochemical corrosion resistance and chloride resistance after cracking compared to UHPC with steel fibers, conforms to reinforce or repair marine structures. The interfacial performance between UHPC with MBFs and normal concrete (NC) urgently needs to be studied. Six kinds of UHPC, which were reinforced with MBFs, steel fibers and polypropylene (PP) fibers with various contents, were designed. A Double-sided direct shear test was conducted to study the effects of fibers in UHPC on the interfacial performance between UHPC and NC with different interface treatments. According to the test results, the interfacial shear strength (IFSS) between UHPC and NC increased and gradually approached the upper limit with the increasing fiber-UHPC bonding strength, content, aspect ratio and modulus of fibers. The interfaces processing method had a more significant influence on the IFSS compared to the fibers in UHPC. The group with two grooves had the highest IFSS of 6.57 MPa, representing a 242 % increase compared to the group with smooth interfaces. Semi empirical formulas fully considering the effects of fibers in UHPC were proposed based on tests results and cohesion, and it showed a reliable calculation accuracy with the prediction errors of most groups which were less than 15 %.

{"title":"Experimental study on the interfacial shear performance between macro basalt fibers reinforced UHPC as repair material and normal concrete","authors":"Zhiyuan Chen , Xin Wang , Lining Ding , Kaidi Jiang , Fusheng Niu , Hua Wang , Zhishen Wu","doi":"10.1016/j.engstruct.2025.120044","DOIUrl":"10.1016/j.engstruct.2025.120044","url":null,"abstract":"<div><div>The novel ultra high performance concrete (UHPC) reinforced with macro basalt fibers (MBFs), which has better performance of fiber distribution, electrochemical corrosion resistance and chloride resistance after cracking compared to UHPC with steel fibers, conforms to reinforce or repair marine structures. The interfacial performance between UHPC with MBFs and normal concrete (NC) urgently needs to be studied. Six kinds of UHPC, which were reinforced with MBFs, steel fibers and polypropylene (PP) fibers with various contents, were designed. A Double-sided direct shear test was conducted to study the effects of fibers in UHPC on the interfacial performance between UHPC and NC with different interface treatments. According to the test results, the interfacial shear strength (IFSS) between UHPC and NC increased and gradually approached the upper limit with the increasing fiber-UHPC bonding strength, content, aspect ratio and modulus of fibers. The interfaces processing method had a more significant influence on the IFSS compared to the fibers in UHPC. The group with two grooves had the highest IFSS of 6.57 MPa, representing a 242 % increase compared to the group with smooth interfaces. Semi empirical formulas fully considering the effects of fibers in UHPC were proposed based on tests results and cohesion, and it showed a reliable calculation accuracy with the prediction errors of most groups which were less than 15 %.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"332 ","pages":"Article 120044"},"PeriodicalIF":5.6,"publicationDate":"2025-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143580848","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

Advancing the non-local damage approach for reinforced concrete structures: The Extended Gradient Damage Model

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-03-07 DOI: 10.1016/j.engstruct.2025.119970

Liang Xue , Ye Feng , Lu Hai , Xiaodan Ren , Jie Li

Objective simulation of reinforced concrete (RC) structure, which is insensitive to the mesh size and orientation, is still a challenging task in engineering. In response, this study combines the extended gradient damage (EGD) model with energy decomposition, focusing on predicting the failure behavior of RC with openings. The EGD model adopts a strategy of decoupling the cohesive laws and the damage evolution, thus solving the damage unloading problem inherent in the phase-field models and the gradient-enhanced damage models. Additionally, the EGD model allows for the flexible assignment of tensile and shear mechanical properties to materials. This flexibility eliminates the constraint in the fracture phase-field model that requires the tensile fracture energy to equal the shear fracture energy, thereby enabling more accurate predictions of failure in engineering structures. Since the EGD model diffuses the crack into a damage band that spans multiple elements, the prediction results are independent of the mesh size and shape. Complex fracture patterns can also be reproduced through energy decomposition. In order to efficiently model and predict the failure of RC structures, an explicitly parallel numerical algorithm is developed in this study and integrated into the commercial software ABAQUS. Finally, through a series of numerical examples, it is demonstrated that the EGD model can effectively predict the crack path and global response of RC structures.

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引用次数: 0

Behavior of shear connection in web-embedded U-shaped steel-concrete composite beams: Experimental and numerical study

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-03-07 DOI: 10.1016/j.engstruct.2025.120020

Wenxu Yan , Yuanlong Yang , Guobiao Lou , Yohchia Frank Chen

This paper presents a study on the longitudinal shear connection of a web-embedded U-shaped steel-concrete composite beam (WUSCCB). A push-out test of nine specimens was conducted, and a longitudinal shear bearing mechanism of WUSCCB flange-web interface was proposed. Different from conventional steel-concrete composite beams, the longitudinal shear force at WUSCCB flange-web interface is contributed by both the local compression between shear connectors and surrounding concrete and the longitudinal shear of concrete flange. A finite element analysis was also conducted, revealing the shear mechanism of embedded shear connectors. Subsequently, a parametric analysis including 39 models was carried out to investigate the effects of concrete strength and connector details on the shear resistance behavior, revealing that the width and thickness of connectors are the crucial factors of shear capacity. Based on the test and parametric analysis results, a shear connection design method is proposed. Finally, a finite element model of WUSCCB was developed to verify the design method by examining the relationship between WUSCCB flexural behavior and shear connection degree.

{"title":"Behavior of shear connection in web-embedded U-shaped steel-concrete composite beams: Experimental and numerical study","authors":"Wenxu Yan , Yuanlong Yang , Guobiao Lou , Yohchia Frank Chen","doi":"10.1016/j.engstruct.2025.120020","DOIUrl":"10.1016/j.engstruct.2025.120020","url":null,"abstract":"<div><div>This paper presents a study on the longitudinal shear connection of a web-embedded U-shaped steel-concrete composite beam (WUSCCB). A push-out test of nine specimens was conducted, and a longitudinal shear bearing mechanism of WUSCCB flange-web interface was proposed. Different from conventional steel-concrete composite beams, the longitudinal shear force at WUSCCB flange-web interface is contributed by both the local compression between shear connectors and surrounding concrete and the longitudinal shear of concrete flange. A finite element analysis was also conducted, revealing the shear mechanism of embedded shear connectors. Subsequently, a parametric analysis including 39 models was carried out to investigate the effects of concrete strength and connector details on the shear resistance behavior, revealing that the width and thickness of connectors are the crucial factors of shear capacity. Based on the test and parametric analysis results, a shear connection design method is proposed. Finally, a finite element model of WUSCCB was developed to verify the design method by examining the relationship between WUSCCB flexural behavior and shear connection degree.</div></div>","PeriodicalId":11763,"journal":{"name":"Engineering Structures","volume":"332 ","pages":"Article 120020"},"PeriodicalIF":5.6,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143571507","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

Novel filler-free buckling-restrained steel energy dissipation devices: Cyclic behavior and failure mechanism

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-03-07 DOI: 10.1016/j.engstruct.2025.120032

Zhanhong Zhang , Bin Wang , Theodore L. Karavasilis , Peng Chen , Mengtao Wu

The concept of self-centering structures has emerged in recent years to enhance seismic resilience under strong earthquakes. In self-centering structural systems, seismic damage is typically designed to be concentrated on energy dissipation (ED) devices that can be easily repaired or replaced after an earthquake. Among various ED devices, buckling-restrained steel bar-type dissipaters have received widespread attention due to their excellent hysteresis behavior. Traditionally, these types of dissipaters are designed with a reduced section (i.e., fuse part) surrounded by a steel confining tube, and the gap between them is filled with grout or epoxy to prevent global buckling of the steel bar under tension–compression cyclic loading. However, there is no doubt that such design concept faces several challenges in practical applications, including grouting difficulties, low material utilization, and laborious machining due to the reduced section in the fuse part. To address these issues, this paper presents a novel type of filler-free buckling-restrained ED device to overcome the abovementioned limitations of conventional steel bar-type dissipaters. The design concept of the proposed ED devices was illustrated first. Subsequently, cyclic behavior and failure mechanism of the proposed ED devices were investigated experimentally under quasi-static cyclic loading. Test results show that all specimens exhibit satisfactory hysteresis loops with stable ED capability under different loading conditions. The failure modes of all specimens concentrate in the fuse parts, and there is no out-of-plane bending instability failure due to the constraint provided by the additional restrained sleeves. Moreover, a practical evaluation method was proposed to prevent the out-of-plane bending instability of the proposed devices in seismic applications.

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引用次数: 0

Reinforcement-learning empowered adaptive piezoelectric metamaterial for variable-frequency vibration attenuation

IF 5.6 1区工程技术 Q1 ENGINEERING, CIVIL

Engineering Structures

Pub Date : 2025-03-07 DOI: 10.1016/j.engstruct.2025.120013

Wangpeng Huang , Wei Tang , Zhenwei Chen , Lihua Tang , Chong Chen , Longfei Hou

The complex environmental and variable-frequency excitation necessitate the adaptive capabilities of elastic metamaterials in vibration attenuation applications. This paper introduces an AI-empowered adaptive metamaterial featuring locally resonant units with each comprising a piezoelectric transducer, a voltage-controlled synthetic inductor and a digital control circuit. To overcome the frequency misalignment caused by uncertain variations in the equivalent capacitance of piezoelectric elements, a learning-based strategy is proposed for bandgap tuning to adapt to external changes. Specifically, a Twin Delayed Deep Deterministic policy gradient (TD3) agent is customized for the metamaterial tuning task, and a data-driven simulation environment is constructed based on it. Subsequently, the agent is trained offline to explore the optimal unified control strategy. To compensate for electrical differences among piezoelectric resonate units, a dual-stage strategy is tailored to deploy the learned policy. Experimental results confirm that the proposed method endows the metamaterial beam to achieve the optimal tuning of the vibration attenuation characteristics in the variable-frequency environment.

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引用次数: 0