• International Journal of High-Rise Buildings
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• v.12 no.2
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• pp.107-120
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• 2023

Tall buildings are frequently decried as unsustainable due to their excessive energy usage. Early skyscrapers used natural light and ventilation to facilitate human comfort and applied organic materials such as stone, glass, wood, concrete, and terra cotta for cladding and finishes. With the advent of fluorescent lighting, modern heating, ventilation, air-conditioning (HVAC) systems, and thermally sealed curtain walls, tall office buildings no longer had to rely on natural light and ventilation to provide comfort. Energy efficiency was not a significant factor when the operational costs of buildings were relatively inexpensive. However, today's skyscrapers must become more energy-efficient and sustainable due to energy crises and climate change. This paper highlights vital energy-efficient design principles and demonstrates with illustrative case studies how they are applied to tall buildings in various parts of the world. It shows how sustainable environmental systems do not act alone but are integrated with advanced curtain wall systems, sky gardens, and atria, among others, to regulate and sustain thermal comfort and conserve energy.

• Steel and Composite Structures
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• v.49 no.1
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• pp.47-64
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• 2023

Due to their efficient use of materials, hybrid reinforced concrete-steel (RCS) systems provide more practical and economic advantages than traditional steel and concrete moment frames. This study evaluated the seismic design factors and response modification factor 'R' of RCS composite moment frames composed of reinforced concrete (RC) columns and steel (S) beams. The current International Building Code (IBC) and ASCE/SEI 7-05 classify RCS systems as special moment frames and provide an R factor of 8 for these systems. In this study, seismic design parameters were initially quantified for this structural system using an R factor of 8 based on the global methodology provided in FEMA P695. For analyses, multi-story (3, 5, 10, and 15) and multi-span (3 and 5) archetypes were used to conduct nonlinear static pushover analysis and incremental dynamic analysis (IDA) under near-field and far-field ground motions. The analyses were performed using the OpenSees software. The procedure was reiterated with a larger R factor of 9. Results of the performance evaluation of the investigated archetypes demonstrated that an R factor of 9 achieved the safety margin against collapse outlined by FEMA P695 and can be used for the design of RCS systems.

• Advances in concrete construction
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• v.9 no.6
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• pp.589-596
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• 2020

In an effort to find alternate, environment friendly and sustainable building materials, the scope of possible utilization of iron slag (I-sand), generated as a by-product in iron and steel industries, as fine aggregates in reinforced cement concrete (RCC) made with manufactured sand (M-sand) is examined in this manuscript. Systematic investigations of the physical, mechanical, microstructural and durability properties of I-sand in comparison with RCC made with M-sand have been carried out on various mix designs prepared by the partial/full replacement of I-sand in M-sand. The experimental results clearly indicate the possibility of utilizing iron slag for preparing RCC in constructions without compromising on the property of concrete, durability and performance. This provides an alternate possibility for the effective utilization of industrial waste, which is normally disposed by delivering to landfills, in building materials which can reduce the adverse environmental effects caused by indiscriminate sand mining being carried out to meet the growing demands from construction industry and also provide an economically viable alternative by reducing the cost of concrete production.

• Journal of Construction Engineering and Project Management
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• v.2 no.4
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• pp.20-24
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• 2012

Construction while being an economic activity that provides facilities and infrastructure, it is beneficial to man in some aspects and detrimental in others. There have been environmental concerns related to construction activities globally which mainly focus on atmospheric emissions, depletion of natural resources and energy issues. This study was carried out to assess the impacts of construction activities on the environment in Iganga Municipality and to propose measures for their mitigation. The methodology included: review of relevant literature, observations of the general environmental effects of construction activities, focus groups and a survey conducted among construction industry role players to determine their perceptions and opinions regarding environmental impact of construction activities. The collected data was presented in tabular form and analysed by description of responses to questions. The study revealed that forests were the most greatly degraded due to high demand of timber for construction followed by wetlands degradation. The findings of this study will be useful to architects, designers and builders in order to carefully design buildings and other infrastructure that are environmentally friendly and sustainable. Construction materials and their mode of acquisition are harmful threats to the environment. There is need to reduce the consumption of these materials through recycling and reusing wastes to reduce on waste generation, use of virgin materials and the subsequent waste of energy used in new material production.

• Korean Journal of Agricultural Science
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• v.38 no.3
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• pp.541-547
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• 2011

Korean building industry was developed by concrete and steel construction. However, concrete and steel have some problems which low carbon storage capability and difficulty of recycling. According to many studies, timber has high carbon storage capability, high recycling capability and sustainable supporting capability. Focus on this factors of timber, make new wall structure as Green Timber Wall panels and check the shear performance to use wall system in housing construction such as light-weight timber construction and nondearing wall on other construction. In the results, B-4-B and B-4-S show similar modulus of shear stiffness on the table. GH-4-GH has slip shape failure mode between Green Timber Wall boards. GH-4-GV has most stable characteristic curve than other specimens.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.11 no.2
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• pp.7-11
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• 2015

Recently, as the demand for sustainable energy sources is increasing, ground-source heat pump (GSHP) systems are receiving growing attention. However, the initial cost of GSHP system is higher than it of the conventional systems, especially, in small-size buildings. Therefore, for the application to the small-size building, it is necessary to develop small-size ground heat exchanger with small-size buildings. In this study, analysis of unit-type heat exchanger due to grouting materials. As a result, 1492.14 W of heat exchange rate was acquired in the condition of cement-silica sand-graphite materials.

• International Journal of Concrete Structures and Materials
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• v.8 no.4
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• pp.289-299
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• 2014

Alkali-activated slag concretes are being extensively researched because of its potential sustainability-related benefits. For such concretes to be implemented in large scale concrete applications such as infrastructural and building elements, it is essential to understand its early and long-term performance characteristics vis-a'-vis conventional ordinary portland cement (OPC) based concretes. This paper presents a comprehensive study of the property and performance features including early-age isothermal calorimetric response, compressive strength development with time, microstructural features such as the pore volume and representative pore size, and accelerated chloride transport resistance of OPC and alkali-activated binder systems. Slag mixtures activated using sodium silicate solution ($SiO_2$-to-$Na_2O$ ratio or $M_s$ of 1-2) to provide a total alkalinity of 0.05 ($Na_2O$-to-binder ratio) are compared with OPC mixtures with and without partial cement replacement with Class F fly ash (20 % by mass) or silica fume (6 % by mass). Major similarities are noted between these binder systems for: (1) calorimetric response with respect to the presence of features even though the locations and peaks vary based on $M_s$, (2) compressive strength and its development, (3) total porosity and pore size, and (4) rapid chloride permeability and non-steady state migration coefficients. Moreover, electrical impedance based circuit models are used to bring out the microstructural features (resistance of the connected pores, and capacitances of the solid phase and pore-solid interface) that are similar in conventional OPC and alkali-activated slag concretes. This study thus demonstrates that performance-equivalent alkali-activated slag systems that are more sustainable from energy and environmental standpoints can be proportioned.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.922-927
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• 2009

Due to the law of use of sustainable alternative energy recently legislated, many public institutions are ordered to use renewable energy. So it gets people's eyes on Geothermal energy system among other suggested renewable energy. Since there is hardly existence of a volcanic region, Geothermal heat pump system is generally used most in Korea. However, the important technology and materials are not localized and further, with only our technical skills it is arduous to popularize and develop Geothermal energy because of lack of revitalization related to the law and the regime for locally suitable Data-base. Moreover, an access of renewable energy is too much hard because of people's low interests about Geothermal energy. But fortunately, the well-studied about Geothermal heat system started to be adopted in many other provinces. Therefore, we study this with intend to popularize and develop Geothermal energy.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.71-72
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• 2022

In the case of free-form buildings, it is difficult to reuse the form for panel production because the shape and size of the interior and exterior panels of the building are different. In general, it is a free-form concrete panel (FCP) production technology using the existing plywood formwork, and the form is produced in a different shape each time and is discarded after only one use. The production of these disposable forms requires enormous resources, including materials, labor and time. Hence, it is necessary to develop innovative forms that can be reused for sustainable FCP construction. In this study, a technology has been developed that combines 3D Plastering Technique (3DPT) to produce FCP. By applying this technology to free-form building projects, the time and cost required for FCP production can be reduced. However, specific studies on the production process for this technology have not been done yet. Therefore, the objective of this study is a basic study of free-form concrete panel production process using 3D plastering technique.

• International conference on construction engineering and project management
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• 2017.10a
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• pp.159-166
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• 2017

Recently, the wooden structure has been revived again as an eco-friendly structure technique. It is the counterattack of the wood material, which has become more recognized as a finishing material pushed by the concrete material in the rapid growth after the Industrial Revolution. However, it is difficult to conclude that this is a tendency of the construction market in the whole country. Perhaps this is a tendency to appear more strongly in Korea. It could be seen by comparing the characteristics of the overseas construction market with Korean's and the advanced constructed case of large-scale wooden structures in overseas. National wooden buildings show own characteristics such as construction methods, materials, and member dimensions of wood structures by country, which could be seen as a result of continuously developing their own technology. However, in Korea, despite its unique wooden structure and technology (Hanok; Korean traditional housing), it has not been developed continuously and treated it only as a living building exhibit. This is evidenced by the fact that only one percent of the building is constructed with traditional wooden building technology. Therefore, there are various efforts to modernize the traditional wooden structure technology, but it still does not reach the level of advanced wooden technology abroad. The characteristics of the Korean wooden building market were analyzed in order to suggest ways to develop the Korean wood structure technology. The characteristics of Hanok construction were analyzed through quantitative criteria to define the main development tasks for Hanok development to propose the long-term development path.