• Earthquakes and Structures
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• 제19권1호
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• pp.59-77
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• 2020

The code static eccentricity model for elastic torsional design of structures has two critical shortcomings: (1) the negation of the inertial torsional moment at the center of mass (CM), particularly for torsionally-unbalanced (TU) building structures, and (2) the confusion caused by the discrepancy in the definition of the design eccentricity in codes and the resistance eccentricity commonly used by engineers such as in FEMA454. To overcome these shortcomings, using the resistance eccentricity model that can accommodate the inertial torsional moment at the CM, interactive relations between shear and torsion are proposed as follows: (1) elastic responses of structures at instants of peak edge-frame drifts are given as functions of resistance eccentricity, and (2) elastic hysteretic relationships between shear and torsion in forces and deformations are bounded by ellipsoids constructed using two adjacent dominant modes. Comparison of demands estimated using these two interactive relations with those from shake-table tests of two TU building structures (a 1:5-scale five-story reinforced concrete (RC) building model and a 1:12-scale 17-story RC building model) under the service level earthquake (SLE) show that these relations match experimental results of models reasonably well. Concepts proposed in this study enable engineers to not only visualize the overall picture of torsional behavior including the relationship between shear and torsion with the range of forces and deformations, but also pinpoint easily the information about critical responses of structures such as the maximum edge-frame drifts and the corresponding shear force and torsion moment with the eccentricity.

• Structural Engineering and Mechanics
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• 제63권1호
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• pp.115-124
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• 2017

In this paper, a different technique to predict the effects of soil-structure interaction (SSI) on seismic response of building systems is investigated. The technique use a machine learning algorithm called Support Vector Regression (SVR) with technical and analytical results as input features. Normally, the effects of SSI on seismic response of existing building systems can be identified by different types of large data sets. Therefore, predicting and estimating the seismic response of building is a difficult task. It is possible to approximate a real valued function of the seismic response and make accurate investing choices regarding the design of building system and reduce the risk involved, by giving the right experimental and/or numerical data to a machine learning regression, such as SVR. The seismic response of both single-degree-of-freedom system and six-storey RC frame which can be represent of a broad range of existing structures, is estimated using proposed SVR model, while allowing flexibility of the soil-foundation system and SSI effects. The seismic response of both single-degree-of-freedom system and six-storey RC frame which can be represent of a broad range of existing structures, is estimated using proposed SVR model, while allowing flexibility of the soil-foundation system and SSI effects. The results show that the performance of the technique can be predicted by reducing the number of real data input features. Further, performance enhancement was achieved by optimizing the RBF kernel and SVR parameters through grid search.

• Journal of the Korean Wood Science and Technology
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• 제44권2호
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• pp.283-293
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• 2016

Owing to an increase in the air tightness of recent buildings, the natural ventilation rate was significantly lowered and the removal of accumulated moisture became difficult in these buildings. The hygrothermal performance of these buildings should be carefully considered to provide comfortable indoor environment by removing the moisture condensation risk and the mold growth potential. In this study, hygrothermal performance of two selected wall structures was investigated based on WUFI simulation program. The results displayed that the indoor temperature had impact on the moisture accumulation in the insulation layer for both modeled walls, showing that lower indoor temperature resulted in higher moisture accumulation, especially in the wood frame structure. Also, the yearly moisture accumulation profile exhibited a downward shift throughout the year by adding a vapour retarder with a lower sd-value. In addition, both of the two walls have condensation risk in winter, due to low temperature level. The wood frame structure has a bigger fluctuation and higher condensation risk than the concrete structure.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2009년도 추계 학술논문 발표대회
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• pp.157-160
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• 2009

The decision of the Form removal time which leads the early assuring strength of the concrete from Apartment construction is the fact which is important from Reducing the period of works and the economical efficiency side. Especially, with Complex building of recent times the same Tall building and Multiple Apartment Site which only follows in upgrade of interior construction of apartment site and shortening the frame construction period becomes very, importantly is the actual condition where the effort which is various for this is attempted. But is caused by with limit and economical efficiency problem of case concrete early strength revelation of most and is not put to practical use is the actual condition. Develops concrete mixture which is a utility from the research which sees hereupon and the effect which is economic leads construction duration shortening under maximizing boil.

• 국제초고층학회논문집
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• 제1권4호
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• pp.271-281
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• 2012

Tianjin Goldin Finance 117 tower has an architectural height of 597 m, total of 117 stories, and the coronation of having the highest structural roof of all the buildings under construction in China. Structural height-width ratio is approximately 9.5, exceeding the existing regulation code significantly. In order to satisfy earthquake and wind-resisting requirements, a structure consisting of a perimeter frame composed of mega composite columns, mega braces and transfer trusses and reinforced concrete core containing composite steel plate wall is adopted. Complemented by some of the new requirements from the latest Chinese building seismic design codes, design of the super high-rise building in high-intensity seismic area exhibits a number of new features and solutions to professional requirements in response spectrum selection, overall stiffness control, material and component type selection, seismic performance based design, mega-column design, anti-collapse and stability analysis as well as elastic-plastic time-history analysis. Furthermore, under the prerequisite of economic viability and a series of technical requirements prescribed by the expert review panel for high-rise buildings exceeding code limits, the design manages to overcome various structural challenges and realizes the intentions of the architect and the client.

• 한국지진공학회논문집
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• 제27권6호
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• pp.293-301
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• 2023

Existing reinforced concrete buildings with seismically deficient details have premature failure under earthquake loads. The fiber-reinforced polymer column jacket enhances the lateral resisting capacities with additional confining pressures. This paper aims to quantify the retrofit effect varying the confinement and stiffness-related parameters under three earthquake scenarios and establish the retrofit strategy. The retrofit effects were estimated by comparing energy demands between non-retrofitted and retrofitted conditions. The retrofit design parameters are determined considering seismic hazard levels to maximize the retrofit effects. The critical parameters of the retrofit system were determined by the confinement-related parameters at moderate and high seismic levels and the stiffness-related parameters at low seismic levels.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.513-518
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• 1999

The objective of this experiment is to observe the elastic and inelastic behaviors of high-rise reinforced concrete frame with infilled masonry. To do this a building frame designed according to Korean seismic code and detailed in the Korean conventional manner was selected. An 1:12 scale plane masonry-infilled frame model was manufactured according to similitude law. Push-over test were performed under the roof displacement control. To simulate the earthquake effect, the lateral force distribution was maintained to be an inversed triangular by using whiffle tree. From the tests, story displacements, lateral story forces, local plastic rotations and the relations between inter-story drift versus story shear are obtained. Based on the test results, conclusions on the characteristics of the elastic and inelastic behaviors of a high-rise reinforced concrete frame with infilled masonry are drawn.

• 산업기술연구
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• 제29권A호
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• pp.19-25
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• 2009

The proper orthogonal decomposition (POD) analysis of vibration of a steel frame structure is performed to extract modal parameters. The theoretical background of the POD method is introduced briefly, and this technique is further applied to free vibration displacements of one bay-two story steel frame structure to extract the modal parameters. From the POD analysis of the steel frame structure, it is found that important modal parameters such as true mode shapes, modal kinematic energy, natural frequencies, and damping ratios can be obtained for the building efficiently and in detail. Therefore, it is concluded that the POD method could be one of the useful techniques in analysis of vibration of structures.

• 국제초고층학회논문집
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• 제8권3호
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• pp.177-183
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• 2019

This paper describes the structural design of a 212 m tall building currently under construction in the Tokiwabashi District Redevelopment Project facing Tokyo Station. In this project there was a requirement to rationally solve many issues arising from the conditions of the redevelopment project. In particular, the following two points were considered to be important from the point of view of structural design. 1) To provide an overhang frame with the perimeter columns on the lower stories inclined, in order to enable a typical floor area that greatly exceeded the limitations of the underground structure shape. 2) To provide high grade seismic performance for the office buildings to be constructed on prime city center land. LSCVCS (Lower Stories Concentrated Vibration Control System) was proposed as the method of rationally designing the overhang frame, which is an extremely disadvantageous element in the structural scheme of the tall building with a large slenderness ratio. LSCVCS is a system to provide effective damping by arranging vibration control devices in a concentrated manner in a lower story with large story height, that produces large deformation in an earthquake. Also, the vibration control devices arranged in the lower story are limited to viscous devices, to take into consideration the residual deformation of the overhang frame after an earthquake. The results of investigations into the specific effects of the system for the seismic design are reported, including Performance-based seismic design.

• Steel and Composite Structures
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• 제41권6호
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• pp.861-871
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• 2021

This study aims at investigating the hysteretic performance of a novel composite wall panel fabricated by infilling aerated concrete blocks into a novel light-steel frame used for low-rise residential buildings. The novel light-steel frame is consisted of two thin-wall rectangular hollow section columns and a truss-beam assembled using patented U-shape connectors. Two bare light-steel frames and two composite wall panels have been tested to failure under horizontal cyclic loading. Hysteretic curves, lateral resistance and stiffness of four specimens have been investigated and analyzed. Based on the testing results, it is found that the masonry infill can significantly increase the lateral resistance and stiffness of the novel light-steel frame, about 2.3~3 and 21.2~31.5 times, respectively. Failure mode of the light-steel frame is local yielding of the column. For the composite wall panel, firstly, masonry infill is crushed, subsequently, local yielding may occur at the column if loading continues. Hysteretic curve of the composite wall panel obtained is not plump, implying a poor energy dissipation capacity. However, the light-steel frame of the composite wall panel can dissipate more energy after the masonry infill is crushed. Therefore, the composite wall panel has a much higher energy dissipation capacity compared to the bare light-steel frame.