{"title":"Enhanced specific stiffness and energy absorption in star-re-entrant hierarchical honeycombs featuring two plateau stages","authors":"Ruihao Li , Yifeng Zhong , Yuxin Tang , Rong Liu","doi":"10.1016/j.tws.2025.113050","DOIUrl":null,"url":null,"abstract":"<div><div>This research introduces an innovative Star-Re-entrant Hierarchical (SRH) honeycomb structure, integrating the benefits of re-entrant and star-shaped configurations within a multi-level hierarchical design. To effectively evaluate the performance of the SRH structure, the 3D Equivalent Cauchy Model (3D-ECM) and 2D Equivalent Plate Model (2D-EPM) were constructed using the Variational Asymptotic Method (VAM). Validation of the 3D-ECM’s accuracy was conducted through uniaxial compression tests in two principal directions and detailed 3D FE simulations, revealing two plateau stages and an X-shaped deformation pattern in the re-entrant direction. Additionally, the 2D-EPM accurately predicted both in-plane auxetic and out-of-plane dome-shaped deformations with displacement errors of less than 5%. The SRH structure exhibited an elastic modulus 1.87 times higher than that of RH structures, along with a 1.5 times greater yield strength. Moreover, the EA and SEA values in the non-re-entrant direction for SRH significantly exceeded those of RH, primarily due to the integration of star-shaped hierarchies that help diminish local stress concentrations. Parametric studies indicated that the thickness ratio and re-entrant angle significantly affected both in-plane and out-of-plane shear modulus and Young’s modulus, whereas the Poisson’s ratio was notably influenced by the star and re-entrant angles. This research underscores the effectiveness of VAM-based models in evaluating SRH structures, offering valuable insights for optimizing their mechanical performance in advanced engineering applications.</div></div>","PeriodicalId":49435,"journal":{"name":"Thin-Walled Structures","volume":"211 ","pages":"Article 113050"},"PeriodicalIF":5.7000,"publicationDate":"2025-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Thin-Walled Structures","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0263823125001442","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, CIVIL","Score":null,"Total":0}
引用次数: 0
Abstract
This research introduces an innovative Star-Re-entrant Hierarchical (SRH) honeycomb structure, integrating the benefits of re-entrant and star-shaped configurations within a multi-level hierarchical design. To effectively evaluate the performance of the SRH structure, the 3D Equivalent Cauchy Model (3D-ECM) and 2D Equivalent Plate Model (2D-EPM) were constructed using the Variational Asymptotic Method (VAM). Validation of the 3D-ECM’s accuracy was conducted through uniaxial compression tests in two principal directions and detailed 3D FE simulations, revealing two plateau stages and an X-shaped deformation pattern in the re-entrant direction. Additionally, the 2D-EPM accurately predicted both in-plane auxetic and out-of-plane dome-shaped deformations with displacement errors of less than 5%. The SRH structure exhibited an elastic modulus 1.87 times higher than that of RH structures, along with a 1.5 times greater yield strength. Moreover, the EA and SEA values in the non-re-entrant direction for SRH significantly exceeded those of RH, primarily due to the integration of star-shaped hierarchies that help diminish local stress concentrations. Parametric studies indicated that the thickness ratio and re-entrant angle significantly affected both in-plane and out-of-plane shear modulus and Young’s modulus, whereas the Poisson’s ratio was notably influenced by the star and re-entrant angles. This research underscores the effectiveness of VAM-based models in evaluating SRH structures, offering valuable insights for optimizing their mechanical performance in advanced engineering applications.
期刊介绍:
Thin-walled structures comprises an important and growing proportion of engineering construction with areas of application becoming increasingly diverse, ranging from aircraft, bridges, ships and oil rigs to storage vessels, industrial buildings and warehouses.
Many factors, including cost and weight economy, new materials and processes and the growth of powerful methods of analysis have contributed to this growth, and led to the need for a journal which concentrates specifically on structures in which problems arise due to the thinness of the walls. This field includes cold– formed sections, plate and shell structures, reinforced plastics structures and aluminium structures, and is of importance in many branches of engineering.
The primary criterion for consideration of papers in Thin–Walled Structures is that they must be concerned with thin–walled structures or the basic problems inherent in thin–walled structures. Provided this criterion is satisfied no restriction is placed on the type of construction, material or field of application. Papers on theory, experiment, design, etc., are published and it is expected that many papers will contain aspects of all three.