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Article
Publication date: 1 September 2015

Meltem Zehra Nevzat and Cemil Atakara

From the 19th century onwards, glass has been used intensively in buildings. During the design process, the importance of aesthetics is very common for architects in general. The…

Abstract

From the 19th century onwards, glass has been used intensively in buildings. During the design process, the importance of aesthetics is very common for architects in general. The application of glass walls as part of the building’s structure has given flexibility in design together with transparency as well as aesthetics.

Structural glass systems have been used in different building types for example office, residential, educational, commercial, transportation, cultural … Beyond the high - rise and high - tech buildings, structural glass systems have been applied also to historic buildings during their conservation process. The adaption of the structural glass system and the opportunity to reuse the existing building are other important aspects to be discussed.

In this article, the literature review will be formed with a brief explanation of transparency in contemporary architecture, structural glass systems focusing on ‘suspended glass systems with pre-stressed cable trusses’ (SGSPCT) which has three application methods; 1) between floor systems 2) independent body systems 3) distance bridging systems and the reusability of existing buildings. The ‘between floor system’ which is commonly used as a contemporary solution technique for historic buildings together with its effects, will also be analysed with the help of a case study, Esma Sultan Mansion. This historic building’s present glass structure will be studied to create an alternative proposal less dependent to the existing building. Another case study will be the Ballapais Abbey. Part of this gothic building (the common room) that has collapsed in the past will be analysed. An independent glass structured annex designed with SGSPCT will be proposed giving joint details of the adaptation to the existing building. This case of study is a literature analysis based on books, internet resources, articles and architectural drawings, like plans, sections and details related to the buildings. Both case studies will be proposing an alternative glass structured annex that is focusing on gained transparency and reusability in respect to the existing historic building.

Details

Open House International, vol. 40 no. 3
Type: Research Article
ISSN: 0168-2601

Keywords

Article
Publication date: 28 May 2020

András Jakab, Viktor Hlavicka, Ágoston Restás and Eva Lubloy

During the building designing, it is very important to deal with the fire resistance of the structures. The designed materials for escape routes should be selected to ensure the…

Abstract

Purpose

During the building designing, it is very important to deal with the fire resistance of the structures. The designed materials for escape routes should be selected to ensure the usability of the structures until the time of escape. Planning affects the glass structures similarly, so these can also be partition walls and load bearing structures, although the latter is less applied on escape routes. The heat protection of the glasses can be improved with heat-protective foils, while fire protection is provided by gel intumescent material.

Design/methodology/approach

To research the topic of fire resistance, laboratory experiments were carried out on small-scaled glass elements with thermal protection foil at Budapest University of Technology and Economics at the Department of Construction Materials and Technologies.

Findings

Fire protection of small model specimens was tested with blowtorch fire and furnace heat load. During the experiments, six foils were tested. Single pane glass, double layered and triple glazed specimens were tested with blowtorch fire.

Originality/value

Fire protection of small model specimens was tested with blowtorch fire and furnace heat load. During the experiments, six foils were tested. Single pane glass, double layered and triple glazed specimens were tested with blowtorch fire. In case of heat-protected glazing, the foils on the “protected” side of the single pane glass do not have a fire protection effect based on blowtorch fire test. For double glassed specimens, the P35 foil has a perceptible effect, even for the requirements of the flame breakthrough (E, integrity), when the foil is placed on the inner side (position 3) of the second glass layer. The stratification of each triple glazed specimens was effective against blowtorch fire load (3 M, S4&P35), so (EI, integrity and isolation) it can meet the requirements of flame breakthrough and thermal insulation.

Details

Journal of Structural Fire Engineering, vol. 11 no. 3
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 4 November 2014

Mica Grujicic, Ramin Yavari, Jennifer Snipes, S. Ramaswami and Roshdy Barsoum

The purpose of this paper is to study the mechanical response of polyurea, soda-lime glass (glass, for short), polyurea/glass/polyurea and glass/polyurea/glass sandwich structures

Abstract

Purpose

The purpose of this paper is to study the mechanical response of polyurea, soda-lime glass (glass, for short), polyurea/glass/polyurea and glass/polyurea/glass sandwich structures under dynamic-loading conditions involving propagation of planar longitudinal shockwaves.

Design/methodology/approach

The problem of shockwave generation, propagation and interaction with material boundaries is investigated using non-equilibrium molecular dynamics. The results obtained are used to construct basic shock Hugoniot relationships associated with the propagation of shockwaves through a homogeneous material (polyurea or glass, in the present case). The fidelity of these relations is established by comparing them with their experimental counterparts, and the observed differences are rationalized in terms of the microstructural changes experienced by the shockwave-swept material. The relationships are subsequently used to predict the outcome of the interactions of shockwaves with polyurea/glass or glass/polyurea material boundaries. Molecular-level simulations are next used to directly analyze the same shockwave/material-boundary interactions.

Findings

The molecular-level simulations suggested, and the subsequent detailed microstructural analyses confirmed, the formation of topologically altered interfacial regions, i.e. polyurea/glass and glass/polyurea interphases.

Originality/value

To the authors’ knowledge, the present work is a first attempt to analyze, using molecular-level simulation methods, the interaction of shockwaves with material boundaries.

Details

Multidiscipline Modeling in Materials and Structures, vol. 10 no. 4
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 3 May 2016

Sangbeom Cho, Venky Sundaram, Rao Tummala and Yogendra Joshi

The functionality of personal mobile electronics continues to increase, in turn driving the demand for higher logic-to-memory bandwidth. However, the number of inputs/outputs…

265

Abstract

Purpose

The functionality of personal mobile electronics continues to increase, in turn driving the demand for higher logic-to-memory bandwidth. However, the number of inputs/outputs supported by the current packaging technology is limited by the smallest achievable electrical line spacing, and the associated noise performance. Also, a growing trend in mobile systems is for the memory chips to be stacked to address the growing demand for memory bandwidth, which in turn gives rise to heat removal challenges. The glass interposer substrate is a promising packaging technology to address these emerging demands, because of its many advantages over the traditional organic substrate technology. However, glass has a fundamental limitation, namely low thermal conductivity (∼1 W/m K). The purpose of this paper is to quantify the thermal performance of glass interposer-based electronic packages by solving a multi-scale heat transfer problem for an interposer structure. Also, this paper studies the possible improvement in thermal performance by integrating a fluidic heat spreader or vapor chamber within the interposer.

Design/methodology/approach

This paper illustrates the multi-scale modeling approach applied for different components of the interposer, including Through Package Vias (TPVs) and copper traces. For geometrically intricate and repeating structures, such as interconnects and TPVs, the unit cell effective thermal conductivity approach was used. For non-repeating patterns, such as copper traces in redistribution layer, CAD drawing-based thermal resistance network analysis was used. At the end, the thermal performance of vapor chamber integrated within a glass interposer was estimated by using an enhanced effective thermal conductivity, calculated from the published thermal resistance data, in conjunction with the analytical expression for thermal resistance for a given geometry of the vapor chamber.

Findings

The limitations arising from the low thermal conductivity of glass can be addressed by using copper structures and vapor chamber technology.

Originality/value

A few reports can be found on thermal performance of glass interposers. However thermal characteristics of glass interposer with advanced cooling technology have not been reported.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 26 no. 3/4
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 August 2016

Beata Synkiewicz

This paper aims to present a method for the reduction of dielectric constant of low-temperature co-fired ceramics (LTCC) substrates with the use of controlled internal porosity.

Abstract

Purpose

This paper aims to present a method for the reduction of dielectric constant of low-temperature co-fired ceramics (LTCC) substrates with the use of controlled internal porosity.

Design/methodology/approach

A glass-ceramic green tape with addition of graphite as a pore former was developed. The green tapes were laminated and then sintered into multilayer structures with porous interior and thin external dense layers. Microstructure of green and fired structures was studied using optical and scanning microscopy. The behavior of the samples during heating was examined in a heating microscope. Impedance spectroscopy was applied for investigation of dielectric properties of the fabricated substrates.

Findings

Microstructure and dielectric properties of the fabricated LTCC structures were compared with the characteristics for non-porous samples with the similar composition. Introduction of 50 Wt.% admixture of graphite in the internal layers of the LTCC substrate was found to result in decrease in dielectric constant value down to about 3. Application of non-porous outer layers improved mechanical strength of the structure and smoothness of its surface, allowing screen printing of conductive pastes on both sides of the substrate.

Practical implications

The rapid growth of the wireless communication industry has created a great demand for the development of new and improved materials and devices operating properly at high frequencies. The fabricated materials can be useful for substrates of microwave devices.

Originality/value

The paper presents an innovative method of dielectric constant decrease of substrate materials. Getting insight into the phenomena responsible for formation of pores is crucial for designing materials for microwave electronics.

Details

Microelectronics International, vol. 33 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 7 August 2017

Beata Synkiewicz, Dorota Szwagierczak and Jan Kulawik

The paper aims to report on fabrication procedure and present microstructure and dielectric behavior of multilayer porous low-temperature cofired ceramic (LTCC) structures based…

164

Abstract

Purpose

The paper aims to report on fabrication procedure and present microstructure and dielectric behavior of multilayer porous low-temperature cofired ceramic (LTCC) structures based on glass-cordierite and glass-alumina.

Design/methodology/approach

The LTCC structures were created as multi-layered composites with dense external layers and inner layers with intentionally introduced porosity. Two preparation methods were applied – subsequent casting of both kinds of slurries and conventional isostatic lamination of dried green tapes arranged in the designed order. Optical microscope observations were carried out to analyze the microstructure of green and fired multilayer structures and pore concentration. To evaluate the adhesion strength of the composite layers, pull test was performed. Dielectric behavior of the composites was studied in the frequency range 50 kHz-2 MHz.

Findings

The fabricated porous LTCC structures showed dielectric constant of 3-5.6. The lowest dielectric constant was attained for glass-cordierite composite made by the conventional tape casting/lamination/firing method from slurry with 50 per cent graphite content. The samples prepared using multiple casting were of worse quality than those fabricated in conventional process, contained irregular porosity, showed tendency for deformation and delamination and exhibited a higher dielectric constant.

Originality/value

Search for new low dielectric constant materials applicable in LTCC technology and new methods of their fabrication is an important task for development of modern microwave circuits.

Details

Microelectronics International, vol. 34 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 1 April 2005

Jaroslav Mackerle

Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming processes or…

5128

Abstract

Purpose

Ceramic materials and glasses have become important in modern industry as well as in the consumer environment. Heat resistant ceramics are used in the metal forming processes or as welding and brazing fixtures, etc. Ceramic materials are frequently used in industries where a wear and chemical resistance are required criteria (seals, liners, grinding wheels, machining tools, etc.). Electrical, magnetic and optical properties of ceramic materials are important in electrical and electronic industries where these materials are used as sensors and actuators, integrated circuits, piezoelectric transducers, ultrasonic devices, microwave devices, magnetic tapes, and in other applications. A significant amount of literature is available on the finite element modelling (FEM) of ceramics and glass. This paper gives a listing of these published papers and is a continuation of the author's bibliography entitled “Finite element modelling of ceramics and glass” and published in Engineering Computations, Vol. 16, 1999, pp. 510‐71 for the period 1977‐1998.

Design/methodology/approach

The form of the paper is a bibliography. Listed references have been retrieved from the author's database, MAKEBASE. Also Compendex has been checked. The period is 1998‐2004.

Findings

Provides a listing of 1,432 references. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Originality/value

This paper makes it easy for professionals working with the numerical methods with applications to ceramics and glasses to be up‐to‐date in an effective way.

Details

Engineering Computations, vol. 22 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 6 August 2018

Kindness A.M. Uyanga, Modestus Okechukwu Okwu, A.O. Adeoye and S.E. Ogbeide

The study aims to carry out the production of a bulk heterojunction organic solar cell in a laboratory scale using a blend of poly (3-hexylthiopene) (P3HT) and [6, 6]-phenyl (C61…

Abstract

Purpose

The study aims to carry out the production of a bulk heterojunction organic solar cell in a laboratory scale using a blend of poly (3-hexylthiopene) (P3HT) and [6, 6]-phenyl (C61) butyric acid methyl ether (PCBM).

Design/methodology/approach

Four inverted geometry organic solar cells were prepared based on 1:1 ratio of P3HT to PCBM and subjected to post annealing at different temperatures of 32, 120, 130 and 140°C. Solar cells were fabricated with structure glass/ITO/P3HT:PCBM/PEDOT:PSS/Au and characterized using Keithley 2400 series sourcemeter and a multimeter interfaced to a computer system with a LabVIEW software, which showed both dark and illumination current–voltage characteristic curves. Four reference cells were also fabricated with structure soda lime glass/P3HT:PCBM and annealed at different temperatures of 32, 120, 130 and 140°C.

Findings

The third organic solar cell prepared, Sample CITO, had the best performance with power conversion efficiency (PCE) of 2.0281 per cent, fill factor (FF) of 0.392, short circuit current of −0.0133 A and open circuit voltage of 0.389 V. Annealing of active layer was found to improve cell morphology, FF and PCE. Annealing of the active layer at 140°C resulted in a decrease of the PCE to 2.01 per cent.

Research limitations/implications

These findings are in good agreement with previous investigation in literature which reported that best annealing temperature for a 1:1 ratio blend of active material is 130°C. Ultraviolet–visible spectra on reference cells showed that sample CITO had wider absorption spectra with peak absorbance at a wavelength of 508 nm.

Originality/value

This research is purely original.

Details

World Journal of Engineering, vol. 15 no. 4
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 1 April 1959

CURIOUSLY little is known about the structure of glass, and many of the properties which can be obtained by heat treatment have been developed on an empirical basis. To study…

Abstract

CURIOUSLY little is known about the structure of glass, and many of the properties which can be obtained by heat treatment have been developed on an empirical basis. To study these problems more thoroughly, particularly with a view to the development of better transparencies for vehicles and aircraft, the Triplex group of companies set up rather more than a year ago their Fundamental Research Laboratories at Balsall Common, near Coventry. Here a total staff of fifteen are provided, in the pleasant surroundings of a house formerly belonging to a country doctor, with facilities for fundamental research on glass structure and properties.

Details

Aircraft Engineering and Aerospace Technology, vol. 31 no. 4
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 11 November 2014

M. Grujicic, R. Yavari, J.S. Snipes, S. Ramaswami and R.S. Barsoum

The purpose of this paper is to address the problems of interaction of tensile stress-waves with polyurea/fused-silica and fused-silica/polyurea interfaces, and the potential for…

Abstract

Purpose

The purpose of this paper is to address the problems of interaction of tensile stress-waves with polyurea/fused-silica and fused-silica/polyurea interfaces, and the potential for the accompanying interfacial decohesion.

Design/methodology/approach

The problems are investigated using all-atom non-equilibrium molecular-dynamics methods and tools. Before these methods/tools are employed, previously determined material constitutive relations for polyurea and fused-silica are used, within an acoustic-impedance-matching procedure, to predict the outcome of the interactions of stress-waves with the material-interfaces in question. These predictions pertain solely to the stress-wave/interface interaction aspects resulting in the formation of transmitted and reflected stress- or release-waves, but do not contain any information regarding potential interfacial decohesion. Direct molecular-level simulations confirmed some of these predictions, but also provided direct evidence of the nature and the extent of interfacial decohesion. To properly model the initial state of interfacial cohesion and its degradation during stress-wave-loading, reactive forcefield potentials are utilized.

Findings

Direct molecular-level simulations of the polyurea/fused-silica interfacial regions prior to loading revealed local changes in the bonding structure, suggesting the formation of an interphase. This interphase was subsequently found to greatly affect the polyurea/fused-silica decohesion strength.

Originality/value

To the authors’ knowledge, the present work is the first public-domain report of the use of the non-equilibrium molecular dynamics and reactive force-field potentials to study the problem of interfacial decohesion caused by the interaction of tensile waves with material interfaces.

Details

International Journal of Structural Integrity, vol. 5 no. 4
Type: Research Article
ISSN: 1757-9864

Keywords

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