• Journal of the Korea Construction Safety Engineering Association
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• s.41
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• pp.88-101
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• 2007

Recently, the condensation of walls often occurring in domestic high-rise apartment buildings is an important problem. The main purpose of this study is to develop the prediction method for the surface condensation on curtain wall in high-rise apartment buildings. Therefore, in this study, we first analyzed exterior climate factors through the analysis of the Seoul climate data and predicted the change of indoor temperature by using Apache program to find the cause of the condensation state and to prevent condensation. Also, according to this result, exterior climate factors and interior factors, which caused the condensation, was examined. The thermal performance of the curtain wall and the range of potential condensation were analyzed to focus on high-rise apartment buildings through computer simulation programs. The results are as $follows;^1$) The frame edge of curtain wall has a higher U-value than in the center by $30%^2$) Because of stack effect, the rooms on the higher floor have a lower external ventilation rate resulting to a higher relative humidity3) Installing a ventilation system($20m^3$/h. person) makes it possible to have a higher external ventilation rate, resulting to a lower relative humidity.

• Structural Engineering and Mechanics
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• v.57 no.4
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• pp.641-656
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• 2016

Reinforced concrete frame buildings with masonry infill walls are one of the most popular structural systems in the world. In most cases, the effects of masonry infill walls are not considered in structural models. The results of earthquakes show that infill walls have a significant effect on the seismic response of buildings. In some cases, the buildings collapsed as a result of the formation of a soft story. This study developed a simple method, called corner opening, by replacing the corner of infill walls with a very flexible material to enhance the structural behavior of walls. To evaluate the proposed method a series of experiments were conducted on masonry infill wall and reinforced concrete frames with and without corner openings. Two 1:4 scale masonry infill walls with and without corner openings were tested under diagonal tension or shear strength and two RC frames with full infill walls and with corner opening infill walls were tested under monotonic horizontal loading up to a drift level of 2.5%. The experimental results revealed that the proposed method reduced the strength of infill wall specimens but considerably enhanced the ductility of infill wall specimens in the diagonal tension test. Moreover, the corner opening in infill walls prevented the slid shear failure of the infill wall in RC frames with infill walls.

• Earthquakes and Structures
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• v.13 no.3
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• pp.289-297
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• 2017

This paper presents seismic performance and reliability evaluation on steel-timber hybrid shear wall systems composed of steel moment resisting frames and infill light frame wood shear walls. Based on experimental observations, damage assessment was conducted to determine the appropriate damage-related performance objectives for the hybrid shear wall systems. Incremental time-history dynamic analyses were conducted to establish a database of seismic responses for the hybrid systems with various structural configurations. The associated reliability indices and failure probabilities were calculated by two reliability methods (i.e., fragility analysis and response surface method). Both methods yielded similar estimations of failure probabilities. This study indicated the greatly improved seismic performance of the steel-timber hybrid shear wall systems with stronger infill wood shear walls. From a probabilistic perspective, the presented results give some insights on quantifying the seismic performance of the hybrid system under different seismic hazard levels. The reliability-based approaches also serve as efficient tools to assess the performance-based seismic design methodology and calibration of relative code provisions for the proposed steel-timber hybrid shear wall systems.

• Structural Engineering and Mechanics
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• v.27 no.2
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• pp.135-148
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• 2007

A new finite shear wall element model and a method for calculation of 3D multi-storied only shear walled or shear walled - framed structures using finite shear wall elements assumed ideal elasto - plastic material are developed. The collapse load of the system subjected to factored constant gravity loads and proportionally increasing lateral loads is calculated with a method of load increments. The shape functions over the element are determined as a cubic variation along the story height and a linear variation in horizontal direction because of the rigid behavior of the floor slab. In case shear walls are chosen as only one element in every floor, correct solutions are obtained by using this developed element. Because of the rigid behavior of the floor slabs, the number of unknowns are reduced substantially. While in framed structures, classical plastic hinge hypothesis is used, in nodes of shear wall elements when vertical deformation parameter is exceeded ${\varepsilon}_e$, this node is accepted as a plastic node. While the system is calculated with matrix displacement method, for determination of collapse safety, plastic displacements and plastic deformations are taken as additional unknowns. Rows and columns are added to the system stiffness matrix for additional unknowns.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.553-557
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• 2013

Roof and exterior wall are designed and constructed in a manner that prevents the accumulation of water within the wall and roof assembly in the formal building. However, in a freeform building there is no clear distinction between exterior wall and roof. In other words, the exterior walls and roof systems of the freeform building are integrated as a surface, unlike the formal building envelope. Therefore, freeform architecture needs a systemized envelope design method to perform functions of exterior wall and roof. However, in many cases, construction methods for roof and exterior wall are applied to freeform buildings without necessary alterations, which lead to incomplete design, leakage, cracks and other problems. Freeform architecture is thus designed and constructed differently from formal buildings. In order to more easily and inexpensively actualize freeform architecture, Building Information Modeling (hereinafter referred to as BIM) has recently been applied in the construction industry. The studies and case analysis are not sufficient to identify the implications and contributions of freeform buildings in future similar projects. Therefore, this research will study design and construction methods for freeform surfaces. This study attempts to analyze the pros and cons of each method for the concrete surface frame, and then presents the panel options for envelope system of the freeform architecture.

• Korean Journal of Construction Engineering and Management
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• v.13 no.3
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• pp.34-42
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• 2012

Green frame technology intended to facilitate the remodeling of apartment housing complexes in Korea and extend their service life has been developed. Green frame design is a Rahmen structure using composite precast concrete members and, unlike a bearing-wall structure, lifting and installing structural members accounts for major steps of structural construction. Therefore, if green frame structure construction is to be scheduled appropriately, systematic lifting plan needs to be developed in advance. Development of lifting plan also requires unit lifting process of composite PC members (columns and beams) that consist of green frame to be analyzed first. Therefore, this study attempts to analyze the lifting process of composite PC members used in green frame structure. To that end, lifting procedure and time of composite PC column and beam are estimated and applied to a project case to analyze the lifting cycle of reference floor. Outcomes produced herein will be used as key data for development of lifting plan in subsequent green frame structure construction.

• Structural Engineering and Mechanics
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• v.11 no.6
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• pp.605-616
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• 2001

The purpose of this study is to investigate the effect of the shear wall location in rigid frames on the dynamic behavior of a roof structure due to vertical and horizontal earthquake motions. The study deals with a gabled long span beam supported by two story rigid frames with shear walls. The earthquake response analysis is carried out to study the responses of the roof: vibration mode, natural period, bending moment and horizontal shear force of the bearings. The study results in the following conclusions: First, a large horizontal stiffness difference between the side frames is caused by the shear wall location, which results in a large vertical vibration of the roof and a large shear force at the side bearings. Second, in this case, the seismic design method for ordinary buildings is not useful in determining the distribution of the static equivalent loads for the seismic design of this kind of long span structures.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1994.10a
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• pp.113-120
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• 1994

Large Concrete Panel Structures behave quite differently from frame or monolithic shear wall structures because of the weakness of Joint in stiffness and strength. The joint experiences large deformation such as shear-slip in vertical and horizontal joint and rocking and crushing in horizontal joint because of localized stress concentration, but the wall panels behave elastically under cyclic loads. In order to describe the nonlinear behavior of the joint in the analysis of PC structures, different analysis technique from that of RC structures is needed. In this paper, for analysis of large concrete panel subassemblage subjected to cyclic loads, the wall panels are idealized by elastic finite elements, and the joints by nonlinear spring elements with various load-deflection relationship. The analytical results are compared with the experimental results on the strength, stiffness, energy dissipation and lateral drift, and the effectiveness of this computer analysis modelling technique is checked.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.228-229
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• 2014

Recently, to ensure the high openness and prospect right of the building, curtain wall system is mainly applied to the high-rise buildings at domestic and overseas. As a result, the use of Structural Sealant is increasing. Structural Glazing Sealant is applied with the glass and AL-FRAME (Mullion) that the strong structural strength is required to hold. However, the structural sealant at the construction site in a variety of external influences, such as wind load, thermal load, uv, chemical pollutants etc, in case of storing condition, if structural sealant stored in high temperature for a long period time, it will not perform well compared with initial performance. In this study, the influence of the performance of one-component structural sealant evaluated for proper storage conditions at the construction site and how to use the non-intended.

• Textile Coloration and Finishing
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• v.20 no.4
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• pp.31-42
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• 2008

Tricrecyl phosphate(TCP)-containing polyurea microcapsules were prepared by interfacial polymerization using aromatic 2,4-toluene diisocyanate(TDI) and ethylenediamine(EDA) as wall forming materials. The effects of the protective colloids of polyvinylalcohol(PVA) and gelatin were investigated through experimentation. The mean size of prepared polyurea microcapsules was smaller and the surface morphology of the microcapsule prepared by the PVA as protective colloid was much smoother than the gelatin. As the concentration of protective colloid increased, the wall membrane of the polyurea microcapsules became more stable, the thermal stability of the wall membrane increased, the mean particle size became smaller, and the particle distribution was more uniform. PET containg microTCPs have a higher activation energy of decomposition, higher char content and lower heat of combustion.