Push-out test on the one end welded corrugated-strip connectors in steel-concrete-steel sandwich structure

2017 ◽  
Vol 24 (1) ◽  
pp. 23-35 ◽  
Author(s):  
Mehdi Yousefi ◽  
Mansour Ghalehnovi
Keyword(s):  
Sandwich Structure ◽  
The One ◽  
Push Out

The Fatigue Performance of High Performance Concrete Composite Girder

2019 ◽  
Author(s):  
C. Xu ◽  
B. Y. Zhang ◽  
Z. H. Hou
Keyword(s):  
High Performance ◽  
High Performance Concrete ◽  
Test Results ◽  
Normal Concrete ◽  
Bending Tests ◽  
Composite Girder ◽  
Tensile Performance ◽  
Negative Bending ◽  
The One ◽  
Push Out

<p>The application of high performance concrete has been increasingly concerned in the negative flexural region of steel‐concrete continuous composite girder because of its favorable tensile performance. However, the unclear cyclic and ultimate performance of a high performance concrete composite girder results to the problems which hinder the further application. In this case, a series of fatigue negative bending tests on HPC composite girders and fatigue push‐out tests on stud connectors in HPC were executed. The test results showed that the fatigue slip in the HPC composite girder was smaller than the normal concrete composite girder, and the fatigue life of stud in HPC was longer than the one in normal concrete. Meanwhile, according to the comparison between the stud fatigue live evaluations and test results, the AASHTO‐based evaluations were comparatively with larger safety redundancy, and JSCE was close to the test results but had smaller safety redundancy.</p>

scholarly journals Horizontal push out tests on a steel-yielding demountable shear connector

2018 ◽  
Author(s):  
George Vasdravellis ◽  
Eliza Feidaki
Keyword(s):  
Concrete Slab ◽  
Shear Connector ◽  
Load Curve ◽  
Sustainable Solutions ◽  
Hollow Core Slab ◽  
Unique Shape ◽  
The One ◽  
Increased Strength ◽  
Push Out

The most common type of a steel concrete composite beam is the one using conventional welded headed studs to connect the top flange of a steel beam to the concrete slab. However, the monolithic structure between the headed studs and the concrete slab prevents the deconstruction of the beam. More sustainable solutions in construction can be achieved by developing demountable connections which allow for fully deconstruction and reuse of all structural systems. This paper presents a novel demountable shear connector for use in steel concrete composite beams in conjunction with precast hollow core slab units. The demountable connection proposed has the advantages of minimal use of in situ concrete required only in specific regions, increased ductility due to the unique shape of the shear connector and since it is not embedded in in situ concrete, it facilitates the deconstruction procedure. Ten horizontal push out tests aiming at investigating the structural performance of the demountable shear connector were carried out. The strength of the connection is predicted  using simple mechanics based on plastic beam analysis. The experimental results showed that the proposed demountable shear connector can achieve increased strength depending on the geometric characteristics of the connector, a ductile slip-load curve and a very high slip capacity. 

scholarly journals Influence of Irrigating Solutions on Push-Out Bond Strenght of Intraradicular Posts to Dentine

2016 ◽  
Vol 18 (1) ◽  
pp. 73
Author(s):  
Mohammad Kaif DDS ◽  
Raj Bis DDS, MSc
Keyword(s):  
Bond Strength ◽  
Failure Mode ◽  
Endodontic Treatment ◽  
Resin Cement ◽  
Chi Square ◽  
Root Canals ◽  
Fiber Posts ◽  
Chi Square Test ◽  
The One ◽  
Push Out

The aim of this study was to evaluate the influence of irrigating solutions commonly used during endodontic treatment on the push-out bond strength of intrarradicular fiber posts to dentin. Thirty single rooted teeth were divided into 3 groups according to the solution used during instrumentation: G1, NaOCL 5.25%; G2, 2% chlorhexidine; G3, distilled water. The root canals were prepared and obturated, and the glass fiber posts were cemented with RelyX ARC®. The specimens were submitted to push-out bond test and the results were analyzed by using the One-way ANOVA. The failure mode data were analyzed using the Chi-square test (P < 0.05). There were no statistically significant differences regarding the irrigant solution factor (P > 0.50). The most predominant failure mode was between posts and resin cement. It was concluded that the different irrigant solutions commonly used in endodontic treatment did not affect the push-out bond strength of fiber posts cemented with resin cement.  

Antiferromagnetic Layer Thickness Dependence of Exchange Bias in Sputter-Deposited Co/CoO/Co Trilayer

2011 ◽  
Vol 675-677 ◽  
pp. 1263-1266
Author(s):  
Jian Wang ◽  
Shinji Muraishi ◽  
Ji Shi ◽  
Yoshio Nakamura
Keyword(s):  
Layer Thickness ◽  
Exchange Bias ◽  
Exchange Coupling ◽  
Sandwich Structure ◽  
Thickness Dependence ◽  
Structural Defects ◽  
Domain State ◽  
Antiferromagnetic Layer ◽  
Sputter Deposited ◽  
The One

We have used ferromagnet/antiferromagnet/ferromagnet sandwich structure to probe the antiferromagnetic layer thickness dependence of exchange bias in sputter-deposited Co/CoO/Co trilayer. The exchange coupling occurring at the upper ferromagnetic/antiferromagnetic interface is always found to be stronger than the one at the lower antiferromagnetic/ferromagnetic interface. The grain growth with increasing antiferromagnetic layer thickness can lead to a gradient of grain size distribution through the whole antiferromagnetic layer. Consequently, the relatively large grains at the upper interface would results in a rougher interface which we treat as structural defects and can significantly enhance exchange bias through domain state model. The slightly decrease of exchange coupling with increasing antiferromgnetic layer thickness indicates that the exchange bias is only governed by the grains that are thermally stable but whose anisotropy energy is low enough to be set.

Developing Guidelines for On-Stream Mechanical Cleaning of a Complex Pipeline Network

2012 ◽  
Author(s):  
Husain Mohammed Al-Muslim ◽  
Nader A. Al-Otaibi ◽  
Mashaan Alshammari
Keyword(s):  
Systematic Approach ◽  
Gap Analysis ◽  
Subject Matter Experts ◽  
Internal Corrosion ◽  
Pipeline Network ◽  
Product Flow ◽  
Different Types ◽  
The One ◽  
Oil Gas ◽  
Push Out

On-stream pipeline cleaning is essential to pipeline operations in terms of maintaining both pipeline efficiency, as well as integrity. Running effective brush cleaning pigs through pipelines will remove accumulated solid debris as well as smoothen the pipe wall. This will reduce pipeline pressure as well as increase product flow. A pig with sealing discs will push out accumulated condensates in gas pipelines and will prevent internal corrosion. The concept is simple, but the implementation is challenging for a complex pipeline network such as the one covered in this paper. The network consists of different types of services both upstream and downstream including oil, gas, and refined products. The pipeline sizes range from 3″ to 56″. The age of pipes vary from 50 years old to new installations and accordingly, their conditions and cleanliness vary. Although pigging is largely based on experience and it is more of an art than a defined science, the complexity of the network needed a systematic approach to develop meaningful and useful guidelines. The approach included conducting gap analysis of current pigging practices in the company, interviews with the senior Operators and subject matter experts, and reviewing the latest literature including manufacturer brochures. The developed guidelines include selection criteria, design, material, as well as measurement effectiveness. The objective of the paper is to present the approach taken to develop the guidelines, as well as to give an overview of the guidelines themselves.

Push-out tests on J-hook connectors in steel–concrete–steel sandwich structure

2013 ◽  
Vol 47 (10) ◽  
pp. 1693-1714 ◽  
Author(s):  
Jia-bao Yan ◽  
J. Y. Richard Liew ◽  
K. M. A. Sohel ◽  
M. H. Zhang
Keyword(s):  
Sandwich Structure ◽  
Push Out

Note on Selection of Coordinate Systems for Geodynamics

1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen
Keyword(s):  
Sea Level ◽  
The Other ◽  
Coordinate Systems ◽  
Mean Sea Level ◽  
The Earth ◽  
The One ◽  
Static Systems ◽  
Selection Of

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.

Nucleation of Disorder in Fe3Al Alloys

1967 ◽  
Vol 25 ◽  
pp. 312-313
Author(s):  
P. R. Swann ◽  
W. R. Duff ◽  
R. M. Fisher
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Annealing Temperature ◽  
Antiphase Domain ◽  
Effect Of Temperature ◽  
Domain Structures ◽  
Transmission Electron ◽  
Domain Boundaries ◽  
Higher Temperature ◽  
The One

Recently we have investigated the phase equilibria and antiphase domain structures of Fe-Al alloys containing from 18 to 50 at.% Al by transmission electron microscopy and Mössbauer techniques. This study has revealed that none of the published phase diagrams are correct, although the one proposed by Rimlinger agrees most closely with our results to be published separately. In this paper observations by transmission electron microscopy relating to the nucleation of disorder in Fe-24% Al will be described. Figure 1 shows the structure after heating this alloy to 776.6°C and quenching. The white areas are B2 micro-domains corresponding to regions of disorder which form at the annealing temperature and re-order during the quench. By examining specimens heated in a temperature gradient of 2°C/cm it is possible to determine the effect of temperature on the disordering reaction very precisely. It was found that disorder begins at existing antiphase domain boundaries but that at a slightly higher temperature (1°C) it also occurs by homogeneous nucleation within the domains. A small (∼ .01°C) further increase in temperature caused these micro-domains to completely fill the specimen.

Fundamental Research into Thin Films in a Developing Country

1972 ◽  
Vol 30 ◽  
pp. 500-501
Author(s):  
J.A. Eades ◽  
E. Grünbaum
Keyword(s):  
Thin Films ◽  
Growth Process ◽  
Empirical Process ◽  
Nucleation And Growth ◽  
Research Groups ◽  
Film Research ◽  
Fundamental Research ◽  
Controlled Deposition ◽  
The One ◽  
The University

In the last decade and a half, thin film research, particularly research into problems associated with epitaxy, has developed from a simple empirical process of determining the conditions for epitaxy into a complex analytical and experimental study of the nucleation and growth process on the one hand and a technology of very great importance on the other. During this period the thin films group of the University of Chile has studied the epitaxy of metals on metal and insulating substrates. The development of the group, one of the first research groups in physics to be established in the country, has parallelled the increasing complexity of the field.The elaborate techniques and equipment now needed for research into thin films may be illustrated by considering the plant and facilities of this group as characteristic of a good system for the controlled deposition and study of thin films.

STM studies of crystal growth

1991 ◽  
Vol 49 ◽  
pp. 374-375
Author(s):  
M. G. Lagally
Keyword(s):  
Crystal Growth ◽  
Molecular Beam ◽  
Chemical Vapor ◽  
Sputter Deposition ◽  
Field Of View ◽  
Scanning Tunneling ◽  
Wide Field ◽  
Tunneling Microscopy ◽  
Wide Field Of View ◽  
The One

It has been recognized since the earliest days of crystal growth that kinetic processes of all Kinds control the nature of the growth. As the technology of crystal growth has become ever more refined, with the advent of such atomistic processes as molecular beam epitaxy, chemical vapor deposition, sputter deposition, and plasma enhanced techniques for the creation of “crystals” as little as one or a few atomic layers thick, multilayer structures, and novel materials combinations, the need to understand the mechanisms controlling the growth process is becoming more critical. Unfortunately, available techniques have not lent themselves well to obtaining a truly microscopic picture of such processes. Because of its atomic resolution on the one hand, and the achievable wide field of view on the other (of the order of micrometers) scanning tunneling microscopy (STM) gives us this opportunity. In this talk, we briefly review the types of growth kinetics measurements that can be made using STM. The use of STM for studies of kinetics is one of the more recent applications of what is itself still a very young field.

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