• Journal of Korean Society of Steel Construction
• /
• v.29 no.6
• /
• pp.435-442
• /
• 2017

A lateral load resisting system is a necessary structural element for the mid- to high-rise modular buildings and concrete cores are known as the most typical lateral load resisting systems in 10- to 20-story modular buildings. It is difficult to construct a concrete core simultaneously with the installation and finishing work of modular units because concrete placed using wet methods might contaminate or destroy the modular unit. Therefore, we have developed a hybrid PC (precast concrete) panel construction method that can construct a concrete core together with the installation of modular units. The hybrid PC panel is a load-bearing element in which a pair of C-shaped beams are combined at the top and bottom of a concrete wall. Concrete cores can be constructed by dry method to connect the hybrid PC panels with bolts. In this study, the details and connection of hybrid PC panels are improved to have the lateral performance comparable to reinforced concrete structural walls and are verified through FE analysis.

• Journal of Korean Association for Spatial Structures
• /
• v.5 no.2 s.16
• /
• pp.7-15
• /
• 2005

Currently, the structural material, namely glass fiber reinforced polymer (GFRP) is focused on innovative structure due to lightness, excellent workability and noncorrosive characteristics, etc. However, the lack of GFRP connection technology produces only an imitation of steel and wood structures. This uses univentive design principles as well as unsuitable material applications, causes tons of surplus of materials to be wasted, and results in uneconomical structures, because the characteristics between steel and GFRP are completely different. Thus, this research develops the new, innovative GFRP connection system with considerations of the characteristics of GFRP and adopts it to a mobile und modular membrane pavilion.

• Journal of the Korean housing association
• /
• v.18 no.4
• /
• pp.27-35
• /
• 2007

The use of light steel framing as a method of house construction has increased significantly throughout Japan, United States and Europe. Industrialized unit method are prevailing in developed countries. Unit modular house industry has supported an intensive technical development, and housing systems are now available, which are highly adaptable in form and use. Unit modular house have their own merits and demerits, but the more crucial aspect is that the constant design standard should be applied in each design procedure. It entails the necessity of industrial housing development on the open system basis. This paper describes the general forms of factory product system of unit modular housing system in Korea, United States, Japan. And this study attempts to propose the unit factory product system of which the rate of pre-fabrication is the biggest, that can cope with the demand of user on the basis of open-system.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.27 no.6
• /
• pp.663-672
• /
• 2014

Recently, modular structural systems have been applicable to building construction since they can significantly reduce building construction time. They consists of several unit modular frames of which each beam-column joint employs an access hole for connecting unit modular frames. Their structural design is usually carried out under the assumption that their load-carrying mechanism is similar to that of a traditional steel moment-resisting system. In order to obtain the validation of this assumption, the cyclic characteristics of beam-column joints in a unit modular frame should be investigate. This study carried out finite element analyses(FEM) of unit modular frames to investigate the cyclic behavior of beam-column joints with the structural influence of access holes. Analysis results show that the unit modular frames present stable cyclic response with large deformation capacities and their joints are classified into partial moment connections. Also, this study develops a simple spring model for earthquake nonlinear analyses and suggests the Ramberg-Osgood hysteretic rule to capture the cyclic response of unit modular frames.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.29 no.5
• /
• pp.269-277
• /
• 2017

This study consists of an analysis of pre-existing ceiling construction systems as well as the development of a replacement unitary, lightweight steel ceiling system and related legal standards. Based on the material conditions and progression of the study, appropriate components were chosen and details were modified by mock-up test. A final study model was evaluated for performance and adaptability based on four parameters (indoor environment, constructability, budget economy, and aesthetics) and compared to the pre-existing ceiling system. As a result of the initial study, a lightweight steel design was created consisting of a reinforced structure with modular bars and entry holes for components. This system was hung directly on the suspension structure. The new design increased lighting and acoustic performance adapted to an indoor environment. Moreover, the speed of construction was increased by approximately 30%, the cost was decreased by approximately 20%, and ceiling aesthetics were improved.

• Journal of The Korea Institute of Healthcare Architecture
• /
• v.28 no.3
• /
• pp.7-16
• /
• 2022

Purpose: This study aims to establish the basic directions of the modular airborne infection isolation(AII) ward. Considering a specific function and purposed use as a modular AII ward, it is a chance to derive an address of current modular technology by overview the limitation and improvement of the existing modular architecture. Methods: In addition to the literature analysis on the configuration system of mobile hospitals, research cases on the operational effectiveness of the domestic and foreign mobile construction systems are analyzed. Results: In order to meet the various and strict space guidelines of the AII ward and a chance to improve limitations of uniformed existing modulars, AII modular the negative pressurized care setting should be minimized a structural restriction for reflecting its system on a architectural plan. For this unique requirements, it could be possible to apply various space boxes called infill box which needs to secure a large-scale space. So, a rahmen structure system could be adaptable for this purpose. A dead space between beams of the rahmen structure is to be used for MEP installation. Partial separation, dismantling, and repair should be possible by separating the MEP and infill box from the structure. The infill box must keep 3.5m width under the current Road Traffic Act. Implications: It is necessary to utilize and develop an improved construction method that can reduce the problems of existing steel modular and PC modular.

• Journal of Korean Society of Steel Construction
• /
• v.29 no.5
• /
• pp.331-340
• /
• 2017

This study was performed in order to develop of the new modular construction system. For the modular construction method that is currently applied in the country, it is very expensive in terms of material costs and fire resistance because it uses only the steel C-type beam. In order to overcome this, and the practical application of new steel-PC hybrid module construction system. Improvement and development of the cross-section of the structural beam member in order to be carried out first. An experiment was carried out by making three specimens. Experiment result, the composite beam was dominated by the horizontal shear failure. It was evaluated through a nonlinear analysis and experimental & theoretical for the structural performance the composite beam member.

• Journal of Korean Association for Spatial Structures
• /
• v.16 no.2
• /
• pp.79-88
• /
• 2016

Modular buildings are constructed by assembling modular units which are prefabricated in a factory and delivered to the site. However, due to a problem of noise between floors, concrete slab is usually poured at the top or bottom level of a modular unit in Korea. This greatly increases the weight of buildings, but designing vertical members of modular units to resist overall gravity loads is very inefficient. In this study, considering domestic building construction practices, feasible structural systems for tall modular buildings are proposed in which separate steel frames and reinforced concrete core walls are designed to resist gravity and lateral loads. To verify performance, a three-dimensional structural analysis has been performed with two types of prototype buildings, i.e., a residential building and a hotel. From the results, wind-induced lateral displacements and seismic story drifts are examined and compared with their limit values. Between the two kinds of buildings, the efficiency of the proposed system is also evaluated through a comparison of the weight of structural components. Finally, the effect of a floor diaphragm on the overall behavior is analyzed and discussed.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.22 no.5
• /
• pp.101-109
• /
• 2018

Modular structural systems have been used increasingly for low- and mid-rise structures such as school and apartment buildings. Studies have recently been conducted on the application of the modular structural system to high-rise buildings. To provide sufficient resistances and economical construction for the high-rise modular structural system, a composite unit modular structure was proposed. In this study, the strength of the non-symmetric composite column for the proposed composite unit modular structure was investigated through a series of tests. The experimental study focused on the effect of the slenderness of the column, eccentricity, and through bars on the strength of such a column. Design equations for the non-symmetric column for a modular unit structure were also proposed. From the results, it was found that the proposed design equations provide reasonable strength prediction of the non-symmetric composite column for the modular unit structure.

• Journal of Korean Association for Spatial Structures
• /
• v.20 no.3
• /
• pp.27-34
• /
• 2020

This paper examines the seismic performance and structural design of the ceiling bracket-type modular connection. The bracket-type system reduces the cross-sectional area loss of members and combines units using fitting steel plate, and it has been developed to be fit for medium-story and higher-story buildings. In particular, this study conducted the cyclic loading test for the performance of the C-type and L-type brackets, and compared the results. The test results were also compared with the commercial FEA program. In addition, the structural design process for the bracket-type modular connection was presented. The two connections, proposed as a result of the test results, were all found to secure the seismic performance level of the special moment steel frame. In the case of initial stiffness, the L-type bracket connection was found to be great, but in the case of the maximum moment or fully plastic moment, it was different depending on the loading direction.