• Earthquakes and Structures
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• v.4 no.6
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• pp.649-670
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• 2013

It is known that a base-isolated building exhibits a large response to a long-duration, long-period wave and an inter-connected system without base-isolation shows a large response to a pulse-type wave. To compensate for each deficiency, a new hybrid passive control system is investigated in which a base-isolated building is connected to another building (free wall) with oil dampers. It is demonstrated that the present hybrid passive control system is effective both for pulse-type ground motions and long-duration and long-period ground motions and has high redundancy and robustness for a broad range of disturbances.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.6
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• pp.3-14
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• 2018

The aim of this study is to propose a method for calculating the weight of walking energy in ERAM model by calculating it for the analysis of vertical and horizontal spaces in a building. Conventional theories on the space analysis in the field of architectural planning predict the pedestrian volume of network spaces in urban street or in two-dimensional plane within a building, however, for vertical and horizontal spaces in a building, estimates of the pedestrian volume by those theories are limited. Because in the spatial syntax and ERAM model have been applied weights such as the spatial depth, adjacent angles, and physical distances available only to the two-dimensional same layer or plane. Therefore, the following basic assumptions and analysis conditions in this study were established for deriving a predictor of pedestrian volume in vertical and horizontal spaces of a building. The basic premise of space analysis is not to address the relationship between the pedestrian volume and the spatial structure itself but to the properties of spatial structure connection that human beings experience. The analysis conditions in three-dimensional spaces are as follows : 1) Measurement units should be standardized on the same scale, and 2) The connection characteristics between spaces should influence the accessibility of human beings. In this regard, a factor of walking energy has the attributes to analyze the connection of vertical and horizontal spaces and satisfies the analysis conditions presented in this study. This study has two implications. First, this study has shown how to quantitatively calculate the walking energy after a factor of walking energy was derived to predict the pedestrian volume in vertical and horizontal spaces. Second, the method of calculating the walking energy can be applied to the weights of the ERAM model, which provided the theoretical basis for future studies to predict the pedestrian volume of vertical and horizontal spaces in a building.

• Steel and Composite Structures
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• v.25 no.5
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• pp.535-544
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• 2017

Box sections are symmetrical sections and they have high moment of inertia in both directions, therefore they are good members in tall building structures. For the rigid connection in structures with box column continuity plates are used on level of beam flanges in column. Assembly of the continuity plates is a difficult and unreliable work due to lack of weld or high welding and cutting in the fourth side of column in panel zone, so the use of experimental stiffeners have been considered by researchers. This paper presented an experimental investigation on connection in box columns. The proposed connection has been investigated in four cases which contain connection without internal and external stiffeners(C-0-00), connection with continuity plates(C-I-CP), connection with external vase shape stiffener (C-E-VP) and connection with surrounding plates(C-E-SP). The results show that the connections with vase plates and surrounding plates can respectively increase the ultimate strength of the connection up to 366% and 518% than the connection without stiffeners, in case connection with the continuity plates this parameter increases about 39%. In addition, the proposed C-E-VP and C-E-SP connection provide a rigid and safe connection to acquire rigidity of 95% and 98% respectively. But C-I-CP connection is classified as semi-rigid connections.

• Journal of the Korea Institute of Building Construction
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• v.13 no.5
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• pp.482-490
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• 2013

Although the flat plate system is an efficient structural type due to the simplicity of its construction, the low story height, and the various plan design, the slab-column connections are vulnerable to punching shear failure from gravity load and eccentric shear failure from lateral load. To prevent the structure collapse, various construction methods of slab-column connection reinforcement are developed but none of these satisfies all of structural performance, economics, and constructability. This paper presents the reinforcement of slab-column connection with lattice bars. The structural performance is confirmed with the interior slab-column connection tests subjected to cyclic loading, and the economic feasibility is demonstrated from the structural design under the same condition with lattice bars, stud rails, and stirrups.

• Journal of the Korea Institute of Building Construction
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• v.22 no.5
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• pp.451-462
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• 2022

The objective of the study is to establish a BIM modeling of precast concrete(PC) shear wall with various wall-to-base connections. The family library of PC shear wall was established in BIM program using component function in a IFC(Industry foundation classes) file format and SketchUp program. From the BIM program, the amounts of concrete, reinforcing bars and steel materials as well as the interference of arranged reinforcing bars can be accurately evaluated in the PC shear walls with spliced sleeves, bolt, or welding plate connection methods. Although the additional metallic materials such as steel plates, bolts, and nuts were used in the PC shear walls with welding plate connection method, their amounts of materials, economic efficiency, and environmental impact were similar to those with spliced sleeve connection. Consequently, the bolt or welding connection is a highly applicable method as wall-to-base connection of PC shear walls, and it was a more useful method than spliced sleeve method, particularly considering the constructability.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.11-12
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• 2015

Green Frame is a Rahmen structure made of composite precast concrete members. According to the concrete design code, a lower rebar of precast concrete girder, should be extended to the inner precast concrete column. However, such extension of lower rebar may sharply reduce its constructability. To satisfy the criteria, the connection and anchorage of beam rebar should be taken into consideration, yet it is difficult to use lapping as it is not easy to ensure enough space when Green Frame method is adopted. To solve this, a new method of lower rebar connection and anchorage was developed, and this study is intended to review economic feasibility prior to applying the method developed onto sites. The study result can be used as basic data for selection of the optimal joint and anchorage method for lower rebar of the green frame construction.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.34 no.11
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• pp.23-32
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• 2018

The purpose of this study is to establish a walking energy weighted ERAM model that can predict the pedestrian volume by the connection structure of the vertical and horizontal spaces within a three-dimensional building. The process of building a walking-energy weighted ERAM model is as follows. First, the spatial graph was used to reproduce three-dimensional buildings with vertical and horizontal spatial connection structures. Second, the walking energy was measured on the spatial graph. Third, ERAM model was used to apply weights with spatial connection properties in random walking environment, and the walking energy weights were applied to the ERAM model to calculate the walk energy weighted ERAM values and visualize the distribution of pedestrian flow. To verify the validation of the established model, existing and proposed spatial analysis models were compared to real space. The results of this study are as follows : The model proposed in this study showed as much elaborated estimation of pedestrian traffic flow in real space as in traditional spatial analysis models, and also it showed much higher level of forecasting pedestrian traffic flow in real space than existing models.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.12
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• pp.11-20
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• 2018

The purpose of this study is to investigate the seismic performance of exposed column-base plate strong-axis connections for small-sized steel buildings. Even though the seismic design for small-sized buildings became mandatory since Dec.2017, the arbitrary connection details in steel structure have been applied at the construction site, which is considered to be very insufficient to secure structural safety and stability considering the increased seismic risk. Therefore, a series of experimental test programs had been carried out to develop enhanced connection details in order to ensue the adequate seismic safety of small buildings. The hysteretic behavior of the exposed column-base plate connections commonly used in Korea seem to be very pure poor due to the "Rocking" phenomena between anchor plate and concrete by the residual plastic deformation of anchor bolts. A series of hysteretic tests were conducted to find the solution to overcome the "Rocking" phenomena of the exposed column-base plate connections, finally the stable seismic behavior was obtained by uisng at least 8 anchor bolts with good bonding strength to the protptype specimen.

• Journal of Korean Society of Steel Construction
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• v.24 no.1
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• pp.109-117
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• 2012

This study seeks to devise a design application for a beam structure with partially restrained composite connection to a CFT column. A cost-efficient and stable component is applied by adjusting the stiffness ratio of the column connection through partially restrained composite connection. Based on a review of the structure's stability, it was confirmed that in the case of a low-rise building as a moment frame, resistance without bracing is feasible because stiffness increased by virtue of the partial restrained composite connection by composite action. In the case of a high-rise building, lateral resistance load of moment frame was approximately 10% when proper partial restrained rate was at around 60%. With considerations related to economic efficiency, the partial restriction effect of the beam component was significantly activated by the uniform load, but that of the beam activated by concentrated load was not significantly indicative. The analysis indicated that 60% partial restrained girder at the connection was the most economical in the case of uniform load. It also showed that end moments can be reduced by approximately 25%.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.11a
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• pp.37-41
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• 2002

Lap splice is used in building construction up to recently. As buildings become higher and larger, the use of high tensile bar is increasing due to increasing in the use of high compression concrete. However the using of high tensile bar in lap splice causes eccentricity and difficulty in placing of concrete inside the form, therefore not allowing enough intervening material. Various mechanical connection are being developed but the coupler of today needs either a secondary intervening material or secondary processing that consumes much time. Therefore a coupler, needing neither a secondary intervening material nor secondary processing, was made in this study which lead to following results. (1) Breaking occurred in all experimented rebar. (2) Acquirement of tension exceeding the standard requirement. (3) Acquirement of elongation percentage within the standard requirement.