Compressive Deformation Analysis of Smart Skin Structure Embedded with Round Shape Antenna

2006 ◽  
Vol 321-323 ◽  
pp. 963-967 ◽  
Author(s):  
June Sung Joe ◽  
Hoon Cheol Park ◽  
Kwang Joon Yoon ◽  
Nam Seo Goo
Keyword(s):  
Dielectric Material ◽  
Experimental Tests ◽  
Nonlinear Finite Element ◽  
Deformation Analysis ◽  
Finite Element Analyses ◽  
Antenna Structure ◽  
Round Shape ◽  
Compressive Loads ◽  
Smart Skin ◽  
Structural Layer

In this paper, a smart skin, i.e. a conformal load-bearing antenna structure, which is a multi-layer sandwich structure composed of carbon/epoxy, glass/epoxy and dielectric material, designs, analyses, fabrications and tests are conducted. Mechanical properties of each structural layer of the designed smart skin are obtained from experimental tests. Tests and analyses are conducted to study the deformation behavior of the smart skin under compressive loads. The measured data are compared with the numerical results from geometrically linear/nonlinear finite element analyses. Numerical prediction for the buckling load of the smart skin agreed well with the experimental data.

Parametric Study on Compression Deformation Behavior of Conformal Load-Bearing Smart Skin Antenna Structure

2004 ◽  
Vol 261-263 ◽  
pp. 663-668 ◽  
Author(s):  
Kwang Joon Yoon ◽  
Young Suk Kim ◽  
Young Bae Kim ◽  
J.D. Lee ◽  
Hyun Chul Park ◽  
...  
Keyword(s):  
Parametric Study ◽  
Compressive Load ◽  
Element Model ◽  
Design Data ◽  
Antenna Structure ◽  
Load Bearing ◽  
Shear Moduli ◽  
Design Variables ◽  
Compressive Loads ◽  
Smart Skin

In this paper, a simple conformal load-bearing antenna structure smart skin with a multi-layer sandwich structure composed of carbon/epoxy, glass/epoxy, and a dielectric polymer was designed and fabricated. The mechanical properties of each material in the designed smart skin were obtained from experiments. Tests and analyses were conducted to study the behavior of the smart skin under compressive loads. The designed smart skin failed due to buckling before compression failure. The stresses of each layer and the first failed layer of the smart skin were predicted using MSC/NASTRAN. The finite element model was verified by comparing the numerical results from geometrical linear/nonlinear analyses with the measured data. The numerically predicted structural behavior of the smart skin agreed well with the experimental data. The results showed that the carbon/epoxy layer took charge of most of the compressive load, and the first failure occurred in the dielectric layer while the other layers remained safe. A numerical model was used to obtain design data from the parametric study. The effect of changing the design variables on the buckling and compressive behavior of the smart skin was also investigated. As a result, it was confirmed that the transverse shear moduli of the honeycomb core had a serious impact on the buckling load of the smart skin when the shear deformation was considerable.

Numerical Investigations of Steel Beam-to-Column Connections with Reinforcing Plates

2012 ◽  
Vol 234 ◽  
pp. 78-83
Author(s):  
Marco Valente
Keyword(s):  
Stress Condition ◽  
Welded Joint ◽  
Plastic Hinge ◽  
Experimental Tests ◽  
Nonlinear Finite Element ◽  
Steel Beam ◽  
Finite Element Analyses ◽  
Numerical Investigations ◽  
Access Hole ◽  
Column Joint

This study presents the results of nonlinear finite element analyses performed on improved steel beam-to-column connections with reinforcing plates. The aim is to protect the potentially vulnerable beam-to-column groove welded joint by relocating the plastic hinge away from the column interface. The numerical investigation is based on results from experimental tests carried out on a two-storey steel frame tested at the JRC ELSA Laboratory and involves the modeling of the 3-way beam-to-column joint. The results of the numerical analyses on reinforced joints show that failure indices decrease in the weld region and near the weld access hole compared to the unreinforced connection, but high values of the Triaxiality Index are registered in the weld at the column interface. In order to eliminate the high shear stress in the beam flange and to reduce the high triaxial stress condition at the beam flange-column flange interface, the beam flange was disconnected from the column flange.

Design of flexure revolute joint based on compliance and stiffness ellipsoids

2021 ◽  
pp. 095441002110169
Author(s):  
Jing Zhang ◽  
Hong-wei Guo ◽  
Juan Wu ◽  
Zi-ming Kou ◽  
Anders Eriksson
Keyword(s):  
Finite Element ◽  
Single Point ◽  
Synthesis Method ◽  
Nonlinear Finite Element ◽  
Finite Element Analyses ◽  
Rotational Stiffness ◽  
Rotational Angle ◽  
Parameterized Model ◽  
Flexure Joints ◽  
Translational Stiffness

In view of the problems of low accuracy, small rotational angle, and large impact caused by flexure joints during the deployment process, an integrated flexure revolute (FR) joint for folding mechanisms was designed. The design was based on the method of compliance and stiffness ellipsoids, using a compliant dyad building block as its flexible unit. Using the single-point synthesis method, the parameterized model of the flexible unit was established to achieve a reasonable allocation of flexibility in different directions. Based on the single-parameter error analysis, two error models were established to evaluate the designed flexure joint. The rotational stiffness, the translational stiffness, and the maximum rotational angle of the joints were analyzed by nonlinear finite element analyses. The rotational angle of one joint can reach 25.5° in one direction. The rotational angle of the series FR joint can achieve 50° in one direction. Experiments on single and series flexure joints were carried out to verify the correctness of the design and analysis of the flexure joint.

Experimental and numerical investigation on ultimate strength of four-legged latticed columns

2021 ◽  
pp. 136943322110015
Author(s):  
Yinqi Li ◽  
Feng Liu ◽  
Wenming Cheng ◽  
Huasen Liu
Keyword(s):  
Ultimate Strength ◽  
Structural Engineering ◽  
Analytical Techniques ◽  
Experimental Tests ◽  
Load Carrying Capacity ◽  
Load Carrying ◽  
Compressive Loads ◽  
Initial Geometric Imperfections ◽  
Combined Data ◽  
Loading Eccentricity

Latticed built-up columns are applied more extensively than solid columns in structural engineering because of their excellent load-carrying capacity and light weight. Studies on the bearing capacity of latticed columns, particularly multiple-legged latticed columns, need to be conducted in detail. In this investigation, seven four-legged latticed column specimens of different bar sections, bar distributions and loading eccentricities under compressive loads were subjected to experimental tests. The initial geometric imperfections of the legs and bars were measured and introduced into the FE numerical method. The experimental results were then compared with those of Geometrical and Material Non-Linear Analysis with Imperfection in ABAQUS software. The combined data indicate that the bar section, bar distribution and loading eccentricity significantly influenced the ultimate strength of four-legged latticed columns, producing maximum variations of 105.67%, 65.7% and 48.48%, respectively. This investigation demonstrates the influence of lacing bars and improves the results obtained from FE numerical analytical techniques.

A Novel Approach for Designing Boltless Connectors - Example on a New Drilling Riser Connector

2021 ◽  
Author(s):  
Eleonore Roguet ◽  
Emmanuel Persent ◽  
Daniel Averbuch
Keyword(s):  
Finite Element ◽  
Design Process ◽  
Load Transfer ◽  
Design Method ◽  
Experimental Tests ◽  
New Product ◽  
Block Type ◽  
Finite Element Analyses ◽  
Novel Approach ◽  
Structural Tests

Abstract A new method which uses elastic and elasto-plastic Finite Element analyses is developed to design a double breech-block type connector. All relevant criteria proposed by API16F are fulfilled. In addition, plastic and bearing criteria have been added to support the use of lugs for load transfer in the connector. The proposed methodology has been applied and validated through experimental tests at different scales and in particular on laboratory specimens and small-scaled connectors. Based on these last structural tests, a safety factor of almost 8 was obtained for the design method on small-scaled connectors. Prototype tests at scale 1:1 allowed the methodology to be fully validated and a new product to be qualified. Certification bodies validated the whole design process, the employed methodology and the new connector.

Sign in / Sign up

Export Citation Format

Share Document