• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.4
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• pp.420-427
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• 2022

The present study evaluated the physical, mechanical and thermal properties of the foam glass aggregate and insulation foundation with this, in order to promote the use of insulated foundations using domestically produced foamed glass aggregates. As a result of the evaluation, the compacted foam glass aggregate showed at the same level as overseas products in terms of unit volume mass, particle size and other characteristics, and a compressive strength of 40.6 N/cm², which was superior to the existing organic insulation materials such as XPS. And the thermal conductivity of the foam glass aggregate was 0.84 W/mK, and the thermal transmittance of the specimen simulating the insulation foundation was 0.37 W/mK, so the thermal conductivity of the foam glass aggregate was estimated to be 0.80 W/mK. With these results, it was found that it is possible to use the insulation foundation with re-producted foam glass aggregate by crushing the waste from the process of producing foam glass products.

• Interaction and multiscale mechanics
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• v.5 no.1
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• pp.13-26
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• 2012

In this paper, the wave propagation in a generalized thermo elastic plate embedded in an elastic medium (Winkler model) is studied based on the Lord-Schulman (LS) and Green-Lindsay (GL) generalized two dimensional theory of thermo elasticity. Two displacement potential functions are introduced to uncouple the equations of motion. The frequency equations that include the interaction between the plate and foundation are obtained by the traction free boundary conditions using the Bessel function solutions. The numerical calculations are carried out for the material Zinc and the computed non-dimensional frequency and attenuation coefficient are plotted as the dispersion curves for the plate with thermally insulated and isothermal boundaries. The wave characteristics are found to be more stable and realistic in the presence of thermal relaxation times and the foundation parameter. A comparison of the results for the case with no thermal effects shows well agreement with those by the membrane theory.

• Earthquakes and Structures
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• v.10 no.4
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• pp.939-963
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• 2016

According to the new directives about the rational and efficient use of energy, thermal bridges in buildings have to be avoided, and the thermal insulation (TI) layer should run without interruptions all around the building - even under its foundations. The paper deals with the seismic response of multi-storeyed reinforced concrete (RC) frame building structures founded on an extruded polystyrene (XPS) layer placed beneath the foundation slab. The purpose of the paper is to elucidate the problem of buildings founded on a TI layer from the seismic resistance point of view, to assess the seismic behaviour of such buildings, and to search for the critical parameters which can affect the structural and XPS layer response. Nonlinear dynamic and static analyses were performed, and the seismic response of fixed-base (FB) and thermally insulated (TI) variants of nonlinear RC building models were compared. Soil-structure interaction was also taken into account for different types of soil. The results showed that the use of a TI layer beneath the foundation slab of a superstructure generally induces a higher peak response compared to that of a corresponding system without TI beneath the foundation slab. In the case of stiff structures located on firm soil, amplification of the response might be substantial and could result in exceedance of the superstructure's moment-rotation plastic hinge capacities or allowable lateral roof and interstorey drift displacements. In the case of heavier, slenderer, and higher buildings subjected to stronger seismic excitations, the overall response is governed by the rocking mode of oscillation, and as a consequence the compressive strength of the XPS could be insufficient. On the other hand, in the case of low-rise and light-weight buildings, the friction capacity between the layers of the applied TI foundation set might be exceeded so that sliding could occur.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.107-108
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• 2007

Overhead transmission lines are completely exposed to the environment. This causes faults in transmission lines due to natural environmental conditions. In some cases, transmission towers are damaged by typhoons and snow, as well as sleet on the transmission lines. It takes a lot of time to repair the damaged towers. For emergency restoration purposes, steel poles are installed to temporarily supply power. Before 2003, emergency restoration steel poles were made of angled steel, which required a large number of beams, bolts, etc. In addition, the foundation of the steel pole and ground wire was constructed using excavation and burial methods, therefore it required a lot of manpower and time to construct temporary transmission lines. In September 2003, typhoon Maemi, whose maximum wind speed was 60m/s, hit Korea. 'Maemi' destroyed transmission lines in the Busan and Geojea area, causing long blackouts. To reduce the recovery time to the damaged transmission lines, self-build based emergency towers were developed. self-build based emergency towers reduced recovery time from 24 hours to 4 hours or less. However, the self-build based emergency tower had no arms, so the temporary transmission lines could only be constructed without curves in line routes. In this paper, solving these self-build based emergency tower limitations, using insulated arms(designed for use with the self-build based emergency tower), shall be explained.

• Journal of the Korea Concrete Institute
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• v.26 no.3
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• pp.287-297
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• 2014

Heat of hydration of mass concrete is one of the most important factors that significantly affect structural quality and construction period. Therefore, appropriate methods to control heat of hydration are essential technologies for mass concrete construction. In this study, probability of thermal cracking was checked by thermal analysis prior to the construction of a turbine foundation in a domestic power plant. Subsequently, changes of concrete mix proportion and an effective curing method were proposed to control heat of hydration of mass concrete structures. Concrete manufactured by slag cement was proposed instead of concrete produced by ordinary Portland cement, and an automated curing method was proposed to improve the curing method using typical moist curing with blanket. The automated curing method maintains the temperature difference between center and surface of concrete below a setting value by temperature monitoring. Concrete with slag cement was used for actual construction. One of two identical turbine foundations was cured by an insulated curing method, and the other was cured by the automated curing method to compare the curing methods. And then, the effects of control of heat of hydration were evaluated based on temperature/strain monitoring and crack investigations.

• Journal of the Economic Geographical Society of Korea
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• v.11 no.1
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• pp.24-44
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• 2008

Regulation theories has paid little attention to spatial regulation processes, while it has focused on economic and social regulation processes. More specifically, there have been little researches on regulationist approach to the transformation of the post-socialist system in the context of the space economy. Therefore, the article has attempted to conceptualize the transformation of space economy under the post-socialist system in the light of regulation theories. The space economy could be regarded as the foundation of the reproduction of social relations. Thus, the transformation of post-socialist system has led to the fundamental changes in enterprise and industrial networks as well as social relations in spatial contexts. In this perspective, the research has attempted to identify 'the mode of enterprise regulation' regarded as a codified firm networks by investigating intra-, inter- and extra-firm relations associated with the transformation of post-socialist system. Also, it has intended to suggest three types of the space economy - (1) disembedded economies based on the isolated networks and dissolution of pre-existing networks, (2) embedded economies based on the interaction of institutions and restructuring of networks, and (3) over-embedded economies based on the insulated institutions and endurance of pre-existing networks-in accordance with the governance, institution and networks in the post-socialist system.