Innovative Building Forms Determined by Orthotropic Properties of Folded Sheets Transformed Into Roof Shells

2020 ◽  
Vol 61 (2) ◽  
pp. 111-124
Author(s):  
Aleksandra Prokopska ◽  
Jacek Abramczyk
Keyword(s):  
Computational Models ◽  
High Sensitivity ◽  
Free Form ◽  
Shape Transformation ◽  
Steel Sheets ◽  
Shape Transformations ◽  
Thin Walled ◽  
Orthotropic Properties ◽  
Roof Shells ◽  
Qualitative And Quantitative Characteristics

Qualitative and quantitative characteristics of geometrical and mechanical changes of nominally plane steel sheets folded in one direction, caused by big elastic shape transformations were invented on the basis of the authors' tests, analyzes and computational models of thin-walled folded sheets transformed into shell shapes. Both geometrical and mechanical changes produce significant restrictions in using sheets for shell forms. The deliberate transformations and sheets' characteristics are required to obtain attractive and innovative forms of roof shells and their consistent structures as well as entire buildings. The search for effective solutions related to free forms of buildings and shape transformations of sheets especially in the fields of: shape transformation, effort and stabilization of their walls is necessary due to the high sensitivity of thin-walled open profiles to boundary conditions and loads. A method for shaping such free form buildings that effectively exploit specific orthotropic properties of the transformed sheeting is presented.

Shape transformations of Pt nanocrystals enclosed with high-index facets and low-index facets

CrystEngComm ◽  
2021 ◽  
Vol 23 (38) ◽  
pp. 6655-6660
Author(s):  
Chi Xiao ◽  
Na Tian ◽  
Wei-Ze Li ◽  
Xi-Ming Qu ◽  
Jia-Huan Du ◽  
...  
Keyword(s):  
Potential Method ◽  
High Index ◽  
Shape Transformation ◽  
Square Wave ◽  
Wave Potential ◽  
Shape Transformations ◽  
Pt Nanocrystals

Shape transformation between high-index faceted Pt nanocrystals and low-index faceted ones have been achieved by an electrochemical square-wave potential method.

Experimental Investigations on Spot Welded Built-Up Cold-Formed Steel Beams

2018 ◽  
Vol 1146 ◽  
pp. 142-151
Author(s):  
Viorel Ungureanu ◽  
Ioan Both ◽  
Mircea Burca ◽  
Ştefan Benzar ◽  
Thai Hoang Nguyen ◽  
...  
Keyword(s):  
Spot Welding ◽  
Steel Sheet ◽  
Experimental Program ◽  
Experimental Investigations ◽  
Steel Beams ◽  
Technological Solution ◽  
Research Project ◽  
Steel Sheets ◽  
Cold Formed Steel ◽  
Thin Walled

Within the WELLFORMED research project, ongoing at the CEMSIG Research Center of the Politehnica University of Timisoara, a new technological solution was proposed for built-up beams made of corrugated steel sheets for the web and thin-walled cold-formed steel profiles for the flanges, connected by spot welding. The research project integrates an extensive experimental program on such beams, using full scale specimens, to demonstrate the feasibility of the proposed solutions and to assess their performance, followed by numerical simulations to characterize and optimize the connecting details. The present paper presents the results of a large experimental program, on small specimens subjected to shear, consisting of two or three layers of steel sheet connected by spot welding.

scholarly journals Silo with a Corrugated Sheet Wall

2013 ◽  
Vol 21 (3) ◽  
pp. 19-30 ◽  
Author(s):  
Csaba Németh ◽  
Ján Brodniansky
Keyword(s):  
Computational Models ◽  
Bending Moment ◽  
Physical Models ◽  
Experimental Measurements ◽  
Bending Moments ◽  
Bulk Materials ◽  
Production And Consumption ◽  
Thin Walled ◽  
The Mathematical Model

Abstract Silos and tanks are currently being used to create reserves of stored materials. Their importance is based on balancing the production and consumption of bulk materials to establish an adequate reserve throughout the year. The case study introduced within the framework of this paper focuses on thin-walled silos made of corrugated sheets and on an approach for designing these types of structures. The storage of bulk materials causes compression or tensile stresses in the walls of a silo structure. The effect of a frictional force in the silo walls creates an additional bending moment in a wave, which ultimately affects the resulting bending moments. Several mathematical and physical models were used in order to examine various types of loading and their effects on a structure. Subsequently, the accuracy of the computational models was verified by experimental measurements on a grain silo in Bojničky, Slovakia. A comparison of the experimental and mathematical models shows a reasonable match and confirms the load specifications, while indicating that the mathematical model was correct.

scholarly journals Free-Form Optimization of Thin-Walled Structure for Frequency Response Problem

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Masatoshi Shimoda ◽  
Yang Liu
Keyword(s):  
Frequency Response ◽  
Optimization Method ◽  
Free Form ◽  
Error Norm ◽  
Material Derivative ◽  
Shape Gradient ◽  
Thin Walled Structures ◽  
Target Values ◽  
Gradient Function ◽  
Thin Walled

We present a node-based free-form optimization method for designing forms of thin-walled structures in order to control vibration displacements or mode at a prescribed frequency. A squared displacement error norm is introduced at the prescribed surface as the objective functional to control the vibration displacements to target values in a frequency response problem. It is assumed that the thin-walled structure is varied in the normal direction to the surface and the thickness is constant. A nonparametric shape optimization problem is formulated, and the shape gradient function is theoretically derived using the material derivative method and the adjoint variable method. The shape gradient function obtained is applied to the surface of the thin-walled structure as a fictitious traction force to vary the form. With this free-form optimization method, an optimum thin-walled structure with a smooth free-form surface can be obtained without any shape parameterization. The calculated results show the effectiveness of the proposed method for the optimal free-form design of thin-walled structures with vibration mode control.

SHAPE TRANSFORMATION MODELS AND THEIR APPLICATIONS IN PATTERN RECOGNITION

1990 ◽  
Vol 04 (01) ◽  
pp. 65-94 ◽  
Author(s):  
Z.C. LI ◽  
Y.Y. TANG ◽  
T.D. BUI ◽  
C.Y. SUEN
Keyword(s):  
Pattern Recognition ◽  
Chinese Characters ◽  
Computer Algorithms ◽  
Transformation Models ◽  
Shape Transformation ◽  
Geometric Properties ◽  
Shape Transformations ◽  
Computer Recognition ◽  
Theoretical Analyses

This paper presents linear and bilinear shape transformations including basic transformations, analyzes their geometric properties, and provides computer algorithms. The shape transformations can be used to simplify the recognition of Roman letters, Chinese characters and other pictorial patterns by normalizing their shapes to the standard forms. Important theoretical analyses have been performed to illustrate that the linear and bilinear transformations are applicable to computer recognition of digitized patterns. A number of pictorial examples have been computed to confirm the analyses and conclusions made.

Curved mixed beam elements for the analysis of thin-walled free-form arches

1987 ◽  
Vol 57 (5) ◽  
pp. 361-367 ◽  
Author(s):  
D. Karamanlidis ◽  
R. Jasti
Keyword(s):  
Free Form ◽  
Beam Elements ◽  
Mixed Beam ◽  
Thin Walled

CLINICAL AND INSTRUMENTAL APPROACH TO ENDOTYPING AND BASIC THERAPY OF BRONCHIAL ASTHMA IN CHILDREN

2020 ◽  
pp. 143-152
Author(s):  
Mokina N.A. ◽  
Chertuchina O.B. ◽  
Vdovenko S.A. ◽  
Ponomarev V.A. ◽  
Mokin E.D. ◽  
...  
Keyword(s):  
Bronchial Asthma ◽  
Drug Effects ◽  
High Sensitivity ◽  
Free Form ◽  
Moderate Asthma ◽  
Basic Therapy ◽  
Beta Agonists ◽  
High Doses ◽  
Low Sensitivity ◽  
High Level

To study the significant characteristics of the endotypes of bronchial asthma (BA) in children, with the choice of a personalized, free or fixed form of basic therapy of inhalative corticosteroids and long-active beta agonists (ICS/LABA), 184 people were examined at the sanatorium stage. 6-12 years old, with moderate asthma. When determining the endotypes in this cohort of children with moderate asthma, the key criteria included: the level of nitric oxide in exhaled air (FeNOex), FEV1, body mass index (BMI), and the dynamics of quality of life (QOL). Features of BA endotypes included combinations of the following features: 1) Endotype 1 — low FeNoex level, low BMI, high sensitivity to ICS and LABA preparations, the need to combine the free form of ICS and LABA with non-drug effects; 2) Endotype 2 - average FeNOex level, normal or increased BMI, low sensitivity to ICS and LABA drugs, reduced effectiveness of high doses of IHC, the need to combine the free form of ICS and LABA with non-drug effects; 3) Endotype 3 - a high level of FeNOex, an increased BMI, high sensitivity to a fixed form of administration of ICS and LABA, the inappropriateness of taking ICS and LABA in a free form, reduced effectiveness of low doses of ICS, when taking basic therapy, rapid growth of QOL, against the background of the therapy.

scholarly journals Cylindrical Shells Made of Stainless Steel – Investigation of Postbuckling

2017 ◽  
Vol 25 (2) ◽  
pp. 185-197
Author(s):  
Sebastian Stehr ◽  
Natalie Stranghöner
Keyword(s):  
Stainless Steels ◽  
High Sensitivity ◽  
Economic Advantage ◽  
Wind Loading ◽  
Load Case ◽  
Lightweight Structures ◽  
Stabilization Effect ◽  
Thin Walled ◽  
The University ◽  
Very High

Abstract The relevant load case of open thin-walled shells is often wind loading during construction. Because of the missing stabilization effect of the roof they show a very high sensitivity to buckling which results into higher wall thicknesses. As part of the European RFCS research project BiogaSS the Institute for Metal and Lightweight Structures of the University of Duisburg-Essen carried out investigations on open thin-walled tanks made of austenitic and duplex stainless steels under wind load to study a possible economic advantage which might be gained from the consideration of the elastic postbuckling behaviour. This contribution presents not only experimental and numerical results but also first recommendations regarding the range of possible buckling reduction factors which might be incorporated in future revisions of EN 1993-1-6 and EN 1993-4-2.

SHAPE TRANSFORMATIONS OF VESICLES BUILT OF AMPHIPHILIC MOLECULES

2008 ◽  
Vol 03 (03) ◽  
pp. 397-420 ◽  
Author(s):  
W. T. GÓŹDŹ
Keyword(s):  
Recent Work ◽  
Colloidal Particles ◽  
Spontaneous Curvature ◽  
Shape Transformation ◽  
Rigid Object ◽  
Amphiphilic Molecules ◽  
Shape Transformations ◽  
External Stimuli

We review our recent work on the shape transformations of vesicles subject to external stimuli. Possible shape transformations resulting from the change of the spontaneous curvature, volume, or composition of the components on the surface of a vesicle are examined within the framework of the spontaneus curvature model. The influence of encapsulated or adhered rigid object such as microtubules or colloidal particles on the shape transformation is also investigated. A few cases of shape transformations encountered in experiments are described.

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