Behavior of Polypropylene Filled Cold Formed Steel Profiles – Part B: Torsion

Torsional behaviors of col- formed steel beams are investigated for the webs which are filled by polypropylene. Four I and U profile beams filled with polypropylene were manufactured and tested. In the study, two specimens U100 and two specimens I100 profiles with 1.5 m length and 1.20 mm thickness and thin-walled cold-formed steel profiles were used. The aim of this study is to investigate the torsional behavior of the composite material formed by pouring the polymer material into the U and I profile molds after homogenous pulping. A total of two groups of samples will be obtained: empty cold-formed steel profiles and waste polymer. In this study, finely ground waste and/or raw PP (polypropylene) was used as filling material. The polypropylene is not only improved the torsional behavior strikingly; but also give a way on environmental profit for waste recycling.

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

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1146.142 ◽

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.

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Lateral Flexural-Torsion Buckling of Thin-Walled Cold-Formed Steel Beams with Holes - Design Resistance Evaluation Based on Test Results

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.368-370.1683 ◽

2013 ◽

Vol 368-370 ◽

pp. 1683-1687 ◽

Cited By ~ 1

Author(s):

Marcela Karmazínová

Keyword(s):

Steel Beams ◽

Mathematical Function ◽

Test Results ◽

Resistance Evaluation ◽

Normative Documents ◽

Cold Formed Steel ◽

Design Resistance ◽

Thin Walled ◽

Input Variables ◽

European Standards

The paper is focused on problems of the design resistance of thin-walled cold-formed steel beams with holes, respecting the lateral flexural-torsion buckling effects. The attention is mainly paid to the design resistance determination using the results of experimental verification of the objective resistance and their statistic elaboration and probabilistic evaluation. The lateral buckling of thin-walled beams with holes is a specific problem, because of the holes influence on the torsion stiffness, and usual calculating procedures according to the rules given by the European Standards are not always generally usable. The methods based on the approaches of the design assisted by testing are used for the design resistance evaluation, here. The determination of the design resistance using test results respects the statistic characteristics and probabilistic distribution of all input variables, on which the resistance is depended. This method also takes into account the form of the probabilistic model of the resistance, from the viewpoint of the form of mathematical function and its influence on the resistance variability. The design resistance derivation applying the design assisted by testing can be used as an alternative procedure instead of the design resistance determination according to the normative documents, especially in the cases, when the usual procedures are not sufficiently usable.

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Thin-Walled Cold-Formed Steel Beams with Holes in Lateral Flexural-Torsional Buckling

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.743.170 ◽

2013 ◽

Vol 743 ◽

pp. 170-175 ◽

Cited By ~ 7

Author(s):

Marcela Karmazínová ◽

Jindrich Melcher ◽

Martin Horáček

Keyword(s):

Cross Section ◽

Stability Problem ◽

Design Procedure ◽

Steel Structures ◽

Torsional Stiffness ◽

Steel Beams ◽

Torsional Buckling ◽

Cold Formed Steel ◽

Thin Walled ◽

Flexural Torsional Buckling

In this paper the study on lateral flexural-torsional buckling of steel sigma-cross-section beams with web holes will be presented. The analysis of corresponding stability problem is based on general approach derived for a group of beams including at least mono-symmetric sections loaded transversally to their plane of symmetry. The effective flexural and torsional stiffness of steel beams with holes has been verified by tests. The results of theoretical analysis were compared with specification design procedure and also with actual behaviour of set of beams investigated by experiments. The study conclusions aim to become the background of the supplements to specified provisions for the design of steel structures.

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Torsion in thin-walled cold-formed steel beams

Thin-Walled Structures ◽

10.1016/s0263-8231(00)00011-2 ◽

2000 ◽

Vol 37 (2) ◽

pp. 127-145 ◽

Cited By ~ 25

Author(s):

B.P Gotluru ◽

B.W Schafer ◽

T Peköz

Keyword(s):

Steel Beams ◽

Cold Formed Steel ◽

Thin Walled

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A method for determining the natural moisture content of dentin in a clinical setting

Medical alphabet ◽

10.33667/2078-5631-2020-12-36-39 ◽

2020 ◽

Vol 1 (12) ◽

pp. 36-39

Author(s):

L. V. Iyashvili ◽

Yu. A. Vinnichenko ◽

A. V. Vinnichenko

Keyword(s):

Composite Material ◽

Moisture Content ◽

Computer Program ◽

Clinical Setting ◽

Quantitative Assessment ◽

Critical Mass ◽

Filling Material ◽

Adhesive Interaction ◽

Natural Moisture Content ◽

Hard Tissues

The purpose of the study is a quantitative assessment of the yield of dentinal fluid on the surface of the treated dentin of the tooth when restoring its structure with a composite filling material. To achieve this goal, digital images of the coronal parts of the teeth having formed carious cavities were used; virtual models of hard tissues of teeth recreated using specialized computer programs; A computer program that provides the ability to accurately determine the area of the treated dentin tooth. The results made it possible to draw the following conclusions: with an increase in the depth of the carious cavity, the amount of dentin fluid that can stand out on its surface (1–2 mm from the tooth cavity) sharply increases; with an increase in the area of the formed carious cavity (more than 30 mm2), the risk of release of a critical mass of dentinal fluid (more than 0.4 mg), which can adversely affect the strength of the adhesive interaction between the composite material and the hard tissues of the tooth, increases significantly; the same dynamics is observed with increasing time, at which there is the possibility of free exit of dentinal fluid to the surface of the cavity prepared for filling (more than 45 seconds).

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