Structural Stiffness Research Articles

Shear strength of steel-concrete composite I-beams with corrugated steel webs

Corrugated steel webs have been widely applied to steel-concrete composite beams due to their excellent shear performance. However, there needs to be adequate research on the shear behavior of steel-concrete composite I-beams with corrugated steel webs, and the proportional distribution of shear forces between concrete flanges and corrugated steel webs in composite I-beams has yet to be clarified. This paper experimentally investigates steel-concrete composite I-beams with corrugated steel webs with different shear span ratios. With the increase of the shear span ratio, the shear failure mode of the beam gradually evolves from shear-dominated to flexural-dominated, the shear capacity and structural stiffness of the beam are negatively affected, and the improvement of the shear resistance of the beam after webs buckling is gradually limited. As the primary shear component, corrugated steel webs contribute about 71 % to 92 % of the total sectional shear force. Notably, accounting for 15 % to 35 % of the shear capacity of the beam, the shear contribution of the concrete flange must also be typically considered. For the generalizability of research results, parametric studies are conducted using validated numerical models to comprehensively investigate the effects of steel yield strength, concrete strength, web thickness, web height, and shear span ratio. Afterward, an efficient analytical model considering the shear capacity of the concrete flange is proposed to estimate the shear strength of composite I-beams with corrugated steel webs. The proposed analytical model agrees satisfactorily with experimental and numerical analysis results. The research results can provide valuable support for designing and optimizing steel-concrete composite I-beams with corrugated steel webs.

Seismic performance of pentagonal type aluminum alloy suspen-dome structure with large opening

Prestressing technology is an effective way to enhance the mechanical properties of space structures. In view of this, a new pentagonal type aluminum alloy suspen-dome structure with large opening is proposed in this paper by introducing the lower cable support system into the aluminium alloy single-layer reticulated shell structure. The seismic performance of this new structure is investigated using time-procedure analysis. Firstly, the effects of rise-span ratio, thickness-span ratio, prestressing level, horizontal radius factor for lower chord nodes and roof loading on the free vibration characteristics of the structure with different supporting stiffness are investigated. The distributions of internal forces and displacements of members of overall structure considering lower support and roof structure only are analyzed. Subsequently, the dynamic response of the structure under seismic combinations of different dimensions and directions is investigated, and reasonable combinations that should be considered for simplified analyses are derived. Furthermore, seismic internal force coefficients are introduced to assess the degree of seismic effects on various types of members. On this basis, parametric analysis of the seismic performance of the structural performance is conducted and quantitative assessment of the sensitivity of the parameters is carried out. Additionally, the free vibration characteristics and dynamic performance of steel and aluminium suspen-dome are compared. The results show that considering the supporting structure weakens the structural stiffness while increasing the structural dynamic response; reasonable values of key parameters in the seismic design of the structure are obtained; and the rise-span ratio and thickness-span ratio are important influencing factors of the seismic performance of the structure. Besides, the internal forces of members in aluminium alloy suspen-dome are less affected by seismic effects than those in steel suspen-dome, and the new structure has good seismic performance.

3D printing single‐stroke path planning, local reinforcement and performance testing of MBB beams and cantilever beams

Abstract3D printing of continuous fiber reinforced thermoplastic composites (CFRTPCs) has been applied for the molding of composite complex structures due to the advantages of flexibility and one‐step forming. In this study, feature points simplification, merging and rearrangement were accomplished for Messerschmitt‐Bölkow‐Blohm (MBB) beam and cantilever beam to generate single‐stroke print paths for the specimens. For the significant stress areas in the finite element analysis results of these structures, a local reinforcement method using orthogonal layups was proposed, which was achieved by raising and lowering the print head and adjusting the fiber volume fraction during the printing. After experimental validation and failure modes analysis, the path planning significantly improved the peak load and structural stiffness of the specimens, and the local reinforcement further enhanced the equivalent specific strength and specific stiffness. This study provides a single‐stroke 3D printing strategy for complex structure molding in conjunction with parameter adjustments.Highlights A single‐stroke path planning was developed for MBB beams and cantilever beams, including simplification, merging and rearrangement methods for feature points. A local reinforcement method was proposed, which was achieved by raising and lowering the print head and adjusting the fiber volume fraction during the printing process. The effect of different print paths on specimen properties was investigated.

Design, Simulation, and Fabrication of Composite Lattice Orthoses with Enhanced Structural Performance

Abstract Orthoses play a critical role in rehabilitation by providing fracture stabilization, external load protection, and deformity correction. Traditional methods of orthotic manufacturing often result in reduced breathability leading to potential skin problems, and increased bulkiness and weight due to material and processing limitations. Method: This study aims to enhance breathability and structural performance of orthoses through the utilization of a fiber-reinforced composite lattice design fabricated using a Coreless Filament Winding (CFW) process. An arm brace was designed and manufactured, which incorporates four modules made of fiberglass/polystyrene composite lattices assembled together using adjustable thermoplastic connectors. To simulate the structural performance, a Finite Element Model (FEM) was constructed with careful consideration of the interactions between the connectors and the lattice modules, and this was subsequently validated through experiment. Results: In comparison to a benchmark brace made of Polylactic Acid (PLA) lattice, the composite brace exhibits a significant reduction in thickness (60%) and weight (44%) while maintaining equivalent structural performance. The validation test indicates the FEM's reliability in predicting structural stiffness and strength, with the predicted peak loading being slightly conservative (5%) compared to experimental results. Conclusion: Composite lattice structures represent a significant advancement in the design of breathable, lightweight, and high-strength orthoses. Moreover, the developed FEM serves as a valuable tool for accurately predicting structural performance and optimizing orthotic design under varying loading conditions.

Copper‐graphene coatings for improving thermal shielding of CFRPs through electrodeposition techniques

AbstractToday, carbon fiber reinforced plastics (CFRPs) are materials of interest several industrial sectors because of their mechanical properties and low weight. However, applications in high‐temperature areas are limited because of thermal degradation. Thus, thin coatings acting as thermal shielding and ensuring the upkeep of CFRP structural stiffness are of high interest. This work presents an innovative approach to produce copper/graphene bilayer coatings through electrodeposition and electrophoretic deposition; it consists of laser pre‐treatment of the composite surface to remove the matrix layer exposing the carbon fibers, enabling the subsequent deposition. Bi‐layer graphene/copper coatings exhibit an enhancement in copper electrodeposition efficiency of more than 59% resulting in a 97% stiffness improvement compared to the single layer copper electroplating. All the obtained coatings were able to act as a thermal shield of the CFRPs, reducing the maximum temperature of the composite by more than 60%. In particular, due to the synergistic effect of copper and graphene, the GNPs‐Cu coating achieved the highest maximum temperature reduction (81%). Cross‐sectional analysis indicates severe delamination in uncoated CFRPs, whereas double‐layer coatings maintain structural integrity and prevent delamination even under high‐energy exposure. In addition, the coated composites exhibit a higher electrical conductivity compared to the laser cleaned CFRP, with the GNPs‐Cu coating that obtained a 90% enhancement because of the outstanding electrical properties of copper and graphene.Highlights The laser cleaning pretreatment allows the electrodepositions on CFRPs. The GNP‐Cu scenario achieves the highest deposition efficiency. A 97% stiffness improvement was achieved by GNPs‐Cu scenario. GNPs‐Cu coatings exhibit the utmost reduction in resistivity (98%). The GNPs‐Cu coating achieves the highest thermal shielding performance (81%).

Stiffness properties of regular p-bars tensegrity prisms under the compressive loading

The regular tensegrity prisms are a kind of fundamental unit, which can be formed into different configurations by different splicing approaches to achieve specific structural functions. Taking regular prisms as the research object, this article presents an analytical method for structural deformations under compressive loading. The structural parameters after loading can be obtained directly by solving the nonlinear force density equation, which simplifies the form-finding process. This article also studies the structural stiffness under different connection modes. By defining the twist angle change rate and internal force utilization rate, we can compare the relative deformation of different tensegrity prisms. The results show that the relative deformation of the three-bar prism is minimal, and it has the best stiffness.

A custom pipeline for building computational models of plant tissue

Stalk lodging in the monocot Zea mays is an important agricultural issue that requires the development of a genome-to-phenome framework, mechanistically linking intermediate and high-level phenotypes. As part of that effort, tools are needed to enable better mechanistic understanding of the microstructure in herbaceous plants. A method was therefore developed to create finite element models using CT scan data for Zea mays. This method represents a pipeline for processing the image stacks and developing the finite element models. 2-dimensional finite element models, 3-dimensional watertight models, and 3-dimensional voxel-based finite element models were developed. The finite element models contain both the cell and cell wall structures that can be tested in silico for phenotypes such as structural stiffness and predicted tissue strength. This approach was shown to be successful, and a number of example analyses were presented to demonstrate its usefulness and versatility. This pipeline is important for two reasons: (1) it helps inform which microstructure phenotypes should be investigated to breed for more lodging-resistant stalks, and (2) represents an essential step in the development of a mechanistic hierarchical framework for the genome-to-phenome modeling of herbaceous plant stalk lodging.

Dynamic stability and response of morphing wing structure with time-varying stiffness

Abstract Morphing, adaptable or smart structures are being used in mechanical and aerospace applications in recent years. These structures often have the property of time-varying stiffness or inertial properties, which can cause parametric instability issues that are not well understood. This paper examines the dynamic stability and response of a morphing aircraft wing with periodically time-varying structural stiffness. The wing is modeled as a beam with coupled bending-torsion motion, and parametrically excited stiffness. Aerodynamic loads introduce aerodynamic damping and aerodynamic stiffness to the wing structure. The dynamic and aeroelastic equation of motion resembles a coupled, damped Mathieu-type equation but differs with asymmetric damping and stiffness matrices, and symmetric inertial matrix. Further, these equations are functions of airspeed, magnitude and frequency of parametric excitation. Initially, dynamic stability of the wing is analyzed using Floquet theory, and the instability regions are numerically quantified by stability charts. Subsequently, dynamic responses in the stable and unstable regions are investigated with a Floquet-based Harmonic balance method. The findings reveal that, at zero airspeed, the combination instabilities are eliminated by varying the bending and torsional stiffness with equal magnitudes and frequency. However, as airspeed increases, instability regions shift unevenly, leading to the emergence of new instabilities. Furthermore, the response analysis within stable regions uncovers several unfavorable zones for operating the variable stiffness, where response decay is slower. The results clearly show that parametric excitation can cause unusual phenomena that significantly impact the operation of morphing wings with variable stiffness, which needs to be thoroughly investigated for successful implementation.

Enhancing Building Stability and Seismic Resilience with Water-Added Tuned Mass Dampers

These days, the construction industry is increasingly producing buildings with extremely low damping values. Under structural vibrations caused by storms and earthquakes, structures can collapse easily. There are now several methods for reducing structural vibrations, and one of the methods currently employed is the Tuned Mass Damper (TMD). Research is being conducted to determine its performance and importance. The entire damper was tuned for various constructions. An eight-story model specifically designed for the structure was used in this study to observe the structure's response with and without TMD during shaking table experiments. Compared to passive control devices (PTMDs), Active Tuned Mass Dampers (ATMDs) are more efficient as they are active control devices powered externally. By maintaining the structure's frequency, damping, and stiffness constant, other variables such as the percentage reduction in structural capacity can effectively control structure vibrations. The findings and observations from TMD studies can be used to address challenges in earthquake structural control considering current technological limitations and energy demands. The results illustrate significant improvements with damping: the damped structure experienced a 21% increase in acceleration, a 17% increase in velocity, and a 79% reduction in displacement compared to the un damped structure. These findings underscore the effectiveness of damping in mitigating earthquake-induced vibrations.

An approach for realizing lightweight quasi-zero stiffness isolators via lever amplification

Quasi-zero stiffness (QZS) vibration isolators exhibit excellent performance in low-frequency vibration isolation but require the negative stiffness to be consistent or close to the positive stiffness, which may lead to an excessively large volume or weight of the negative stiffness mechanism. In this paper, a lightweight QZS (L-QZS) vibration isolator using the lever amplification mechanism is developed, theoretically investigated, and experimentally verified. The negative stiffness can be amplified by one order of magnitude through the amplification effect of the lever structure, enabling a lower negative stiffness to compensate for the positive stiffness. Meanwhile, the lever increases the inertia effect of the negative stiffness structure, leading to an increase in the system’s effective mass and further reducing the resonance frequency. Results indicate that with a small negative stiffness, the isolation bandwidth of L-QZS isolators is significantly enlarged. The transmissibility at high frequencies of the L-QZS isolator tends to a certain value, which is mainly determined by the lever ratio and the tip mass of the lever. Furthermore, the negative stiffness can be controlled by adjusting the lever ratio, providing a viable method for matching various positive stiffnesses in engineering applications.

Retrofit of damaged reinforced concrete frame by autoclaved aerated concrete blocks infill wall: Experimental validation and strength estimation

This study introduces a novel approach for the global retrofitting of seismic performance in destructively damaged reinforced concrete (RC) frames through the application of autoclaved aerated concrete (AAC) blocks infill walls to enhance both structural strength and stiffness. Three full-scale RC frames are designed and fabricated, comprising an intact bare frame, a damaged frame strengthened by carbon fiber-reinforced polymer (CFRP), and a damaged frame retrofitted with the same CFRP and AAC blocks infill walls. To verify the cyclic behaviors and working principle of the retrofitted system, the two frames undergo a pre-damage scenario with a maximum inter-story drift ratio (MIDR) of 2.52%, and then both specimens are retrofitted. Afterward, a pseudo-static cyclic test is conducted on three specimens, with a MIDR of 3.36%. The test data is analyzed and discussed in terms of hysteretic responses, secant stiffness, displacement ductility, and energy dissipation capacity. The findings indicate a significant improvement in the lateral strength and stiffness of the seismic-damaged frame through the implementation of AAC blocks infill walls, demonstrating performance comparable to the intact RC frame. Also, the slight local crushing of AAC blocks and their interaction with mortar joints effectively dissipates a considerable amount of input energy, thereby reducing the energy dissipation demands on retrofitted structural components. Moreover, the theoretical deduction of the lateral strength of the retrofitted RC frames is presented. The errors between the predicted and test results fall within 5%, suggesting that the analytical outcomes can reasonably predict the lateral strength of the specimens.

A novel shape sensing approach based on the coupling of Modal Virtual Sensor Expansion and iFEM: Numerical and experimental assessment on composite stiffened structures

Shape sensing, i.e. the reconstruction of the displacement field of a structure from discrete strain measurements, is becoming crucial for the development of a modern Structural Health Monitoring framework. Nevertheless, an obstacle to the affirmation of shape sensing as an efficient monitoring system for existing structures is represented by its requirement for a significant amount of sensors. Two shape sensing methods have proven to exhibit complementary characteristics in terms of accuracy and required sensors that make them suitable for different applications, the inverse Finite Element Method (iFEM) and the Modal Method (MM). In this work, the formulations of these two methods are coupled to obtain an accurate shape sensing approach that only requires a few strain sensors. In the proposed procedure, the MM is used to virtually expand the strains coming from a reduced number of strain measurement locations. The expanded set of strains is then used to perform the shape sensing with the iFEM. The proposed approach is numerically and experimentally tested on the displacement reconstruction of composite stiffened structures. The results of these analyses show that the formulation is able to strongly reduce the number of required sensors for the iFEM and achieve an extremely accurate displacement reconstruction.

Classification Criteria for Axial Disease in Youth with Juvenile Spondyloarthritis.

To develop and validate classification criteria for axial disease in youth with juvenile spondyloarthritis (SpA; AxJSpA). This international initiative consisted of four phases: 1) Item generation; 2) Item reduction; 3) Criteria development; and 4) Validation of the AxJSpA criteria by an independent team of experts in an internationally representative Validation cohort. These criteria are intended to be used on youth with a physician diagnosis of juvenile SpA and for whom axial disease is suspected. Item generation consisted of a systematic literature review and a free-listing exercise using input from international physicians and collectively resulted in 108 items. After the item reduction exercise and expert panel input, 37 items remained for further consideration. The final AxJSpA criteria domains included: imaging: active inflammation, imaging: structural lesions, pain chronicity, pain pattern, pain location, stiffness, and genetics. The most heavily weighted domains were active inflammation and structural lesions on imaging. Imaging typical of sacroiliitis was deemed necessary, but not sufficient, to classify a youth with AxJSpA. The threshold for classification of AxJSpA was a score of ≥55 (out of 100). When tested in the validation data set, the final criteria had a specificity of 97.5% (95% CI: 91.4-99.7), sensitivity of 64.3% (95% CI: 54.9-73.1) and Area Under the Receiver Operating Characteristic (AUROC) curve of 0.81 (95% CI: 0.76-0.86). The new AxJSpA classification criteria require an entry criterion, physician diagnosis of juvenile SpA, and include seven weighted domains. The AxJSpA classification criteria are validated and designed to identify participants for research studies.

Utilizing almond shell filler to improve strength and sustainability of jute fiber composites

AbstractIn recent years, natural fibers have begun to replace synthetic fibers in automotive, building, and marine applications because of their sustainability, renewability, low cost, and availability of raw materials. However, because of their low strength, biocomposites are strengthened by hybridization with stronger synthetic fibers or adding fillers. This study reinforced high‐cellulose jute fiber composites with cellulose‐based almond (Prunus amygdalus) shell filler (ASF). Natural waste almond shells were ground to microparticle size. Hybrid composites were prepared by adding microparticulate ASF to the jute fiber composites at 0%, 1.5%, 3%, 4.5%, and 6% by weight. A comprehensive experimental study included tensile, flexural, Charpy impact (flat and edgewise), and shear tests. The addition of ASF significantly improved the mechanical properties of the jute fiber composites, and the best values were obtained with 3 wt.% ASF addition. Tensile, flexural, impact, and shear properties increased by 48.2%, 63.5%, 24.4%, and 52.2%, respectively. Scanning Electron microscopy (SEM) micrographs used in morphological structural analysis prove that the high mechanical values are achieved by ASF strengthening the interlaminar adhesion. This study contributed to developing a hybrid natural composite material reinforced with natural fillers that is stronger, environmentally friendly, and sustainable.Highlights The organic structure of Almond Shell Filler (ASF) ensured the sustainability of natural composites. Cellulosic ASF significantly contributed to the structural stiffness and strength of jute fiber composites. ASF reduced voids, improved fiber‐matrix bonding, and prevented debonding and delamination. ASF optimized the mechanical performance of jute fiber composites at 3%.

Study on Influence Mechanism of Tunnel Construction on Adjacent Pile Foundation and Resilience Assessment

To guarantee the safety of tunnel construction and the continued use of nearby structures, it is crucial to accurately forecast the size and extent of the plastic region that may occur due to tunnel excavation, as well as examine the impact on resilience. In this paper, the influence mechanism of tunnel construction on adjacent pile foundation and resilience assessment is investigated. Firstly, the stratum deformation and stress induced by tunnel construction are derived based on the thin-walled theory considering the influence of tunnel structure stiffness. Moreover, the resilience assessment based on the characteristics of the stratum plastic region is proposed to describe the degree of disturbance caused by tunnel construction to the adjacent pile foundation. Then, a comparison with a numerical simulation is conducted to verify the correctness of the prediction method of the stratum plastic region proposed in this paper. Finally, parameter sensitivity analysis is carried out, which indicates that pile parameters, soil parameters, and different tunnel outline conditions have a great influence on the prediction results. In order to reasonably control the impact of tunnel construction on the surrounding environment, safety control techniques, including advance grouting reinforcement and grouting uplift, need to be carefully designed.

Structure and Dynamics of Water in Polysaccharide (Alginate) Solutions and Gels Explained by the Core-Shell Model.

In both biological and engineered systems, polysaccharides offer a means of establishing structural stiffness without altering the availability of water. Notable examples include the extracellular matrix of prokaryotes and eukaryotes, artificial skin grafts, drug delivery materials, and gels for water harvesting. Proper design and modeling of these systems require detailed understanding of the behavior of water confined in pores narrower than about 1 nm. We use molecular dynamics simulations to investigate the properties of water in solutions and gels of the polysaccharide alginate as a function of the water content and polymer cross-linking. We find that a detailed understanding of the nanoscale dynamics of water in alginate solutions and gels requires consideration of the discrete nature of water. However, we also find that the trends in tortuosity, permeability, dielectric constant, and shear viscosity can be adequately represented using the "core-shell" conceptual model that considers the confined fluid as a continuum.

Research on Indirect Influence-Line Identification Methods in the Dynamic Response of Vehicles Crossing Bridges

The bridge influence line can effectively reflect its overall structural stiffness, and it has been used in the studies of safety assessment, model updating, and the dynamic weighing of bridges. To accurately obtain the influence line of a bridge, an Empirical and Variational Mixed Modal Decomposition (E-VMD) method is used to remove the dynamic component from the vehicle-induced deflection response of a bridge, which requires the preset fundamental frequency of the structure to be used as the cutoff frequency for the intrinsic modal decomposition operation. However, the true fundamental frequency is often obtained from the picker, and the testing process requires the interruption of traffic to carry out the mode decomposition. To realize the rapid testing of the influence lines of bridges, a new method of indirectly identifying the operational modal frequency and deflection influence lines of bridge structures from the axle dynamic response is proposed as an example of cable-stayed bridge structures. Based on the energy method, an analytical solution of the first-order frequency of vertical bending is obtained for a short-tower cable-stayed bridge, which can be used as the initial base frequency to roughly measure the deflection influence line of the cable-stayed bridge. The residual difference between the deflection response and the roughly measured influence line under the excitation of the vehicle is operated by Fast Fourier Transform, from which the operational fundamental frequency identification of the bridge is realized. Using the operational fundamental frequency as the cutoff frequency and comparing the influence-line identification equations, the empirical variational mixed modal decomposition, and the Tikhonov regularization to establish a more accurate identification of the deflection influence line, the deflection influence line is finally identified. The accuracy and practicality of the proposed method are verified by real cable-stayed bridge engineering cases. The results show that the relative error between the recognized bridge fundamental frequency and the measured fundamental frequency is 0.32%, and the relative error of the recognized deflection influence line is 0.83%. The identification value of the deflection influence line has a certain precision.

Detection of deposits adhered on the back surface of plate-like structures using a scanning laser source technique

An imaging technique using a scanning laser source (SLS) was applied to detect deposits inside pipes, which are necessary for the safe decommissioning of the Fukushima Nuclear Power Plant. Experimental results showed that the more firmly adhered the deposit on the back surface of a flat plate, the clearer it is to obtain an image of the deposit. This result is as expected because the imaging by an SLS technique is dependent on the bending stiffness of the thin plate structure. Furthermore, even epoxy putty as large as 50 mm in diameter adhered to the inner surface of the pipe could be imaged, and even when the receiver device was changed from a piezoelectric device to a non-contact laser doppler vibrometer, the image of the deposit could be obtained properly with some degradation of the image due to the effect of a lower signal-to-noise ratio.

Unsupervised Machine Learning-Driven Assessment of Infill Wall Systems for Structural Performance in Soft Stories

Infill wall systems have been extensively studied as potential solutions to mitigate the adverse effects of stiffness irregularity in soft-storey structures. This research leverages unsupervised machine learning techniques, specifically clustering algorithms, to analyze and compare the mechanical behavior of different columns in a nine-storey unsymmetrical reinforced concrete building subjected to seismic loading. The primary objective is to assess the effectiveness of various infill wall systems, including 5-inch and 10-inch wide brick walls and 5-inch, 7.5-inch, and 10-inch wide concrete walls, in enhancing structural resilience. The study employs a comprehensive data-driven approach, incorporating ETABS modeling, data preprocessing, exploratory data analysis, and clustering to identify patterns and relationships in the structural performance of columns. Key findings indicate that more comprehensive and concrete infill walls significantly reduce displacement values, improving structural stiffness. Cluster analysis reveals that columns connected to multiple infill walls, particularly exterior corner columns, exhibit enhanced structural performance. Specifically, the 10-inch comprehensive concrete infill wall system demonstrated the highest efficacy in mitigating stiffness irregularity. The research further highlights that clustering algorithms, such as K-Means, effectively categorize columns based on their mechanical responses, facilitating a comparative evaluation of infill wall systems. These insights provide valuable recommendations for designing and retrofitting soft-storey structures to enhance seismic resilience.

Bending stiffness analysis of regular polyhedron sandwich structures

Abstract As a new type of sandwich structure, regular polyhedron sandwich structure has excellent structure performances such as high bending resistance and energy-absorbing features. However, the current design process of regular polyhedron sandwich structures often ignores the influence of unit-cell parameters on structural bending stiffness. Based on origami geometry, this study analyzes the geometric characteristics of polyhedron unit-cell structures. A simulation model was established to analyze the bending performance of regular polyhedron sandwich structures. The influence of the number of polyhedron surfaces and similarity transformation parameters on bending stiffness was analyzed by finite element software. Through finite simulation analysis, the influence graph of bending performance in the impact of various parameters was obtained. This analysis provides valuable insights for the optimization design of regular polyhedron sandwich structures.