• Title/Summary/Keyword: buildings (codes)

Search Result 264, Processing Time 0.021 seconds

Light Pollution Survey of Outdoor Lighting in Shopping Complex (쇼핑용 복합빌딩의 옥외조명으로 인한 광공해발생 실태조사)

  • Ahn, Hyun-Tae;Kim, Jeong-Tai
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.18 no.5
    • /
    • pp.16-26
    • /
    • 2004
  • As the importance of outdoor lighting become more widely recognized, outdoor lighting has been installed in many buildings, plazas, landscape, and historical monuments in Korea, Outdoor lighting on showing complex, in particular, express its values as local landmarks. However, the excessive outdoor lighting in the large-scale shopping complex tends to cause light pollution. Many advanced countries are trying to create a comfortable lighting environment by the guidlines and regulations on outdoor lighting to prevent light pollution. For this research backgrounds, the light pollution of three showing complexes in Seoul have been investigated. For the purpose, luminance of building facade, horizontal illuminance, and vertical illuminance were measured with proper measurement instruments and compared the results with the CIE recommendations. The results of the study are as follows. As no cut-off luminaries are currently installed on pedestrian walks, some glare were occured partially. It also shows that the luminance of building facades are high to improve the degree of public awareness of buildings and advertisements. In other words, the luminance of the building facade, when compared with that of the CIE recommendations, is twice as high and the vatical illuminance of pedestrian walks is far higher than that of the CIE recommendations, which proves the existence of light pollution. As Korea has not yet provided proper regulations or guidelines for the control of light pollution, it is necessary to make appropriate codes for it.

Application of Seismic Isolation and Vibration Control in Korea (우리나라의 면진 및 진동제어)

  • Lee, Dong-Guen;Kim, Tae-Ho
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.10 no.6 s.52
    • /
    • pp.67-77
    • /
    • 2006
  • Seismic activity of Korea is not so high as that of Japan or California and most of the structures were designed without considering the influence of earthquakes until the first seismic design code was enforced in 1988. Therefore, it was very hard to find seismically isolated structures in Korea until 1980's. Korean engineers assumed that the seismic isolation or vibration control would be useful only in a high seismicity region while such technologies can be quite useful in a low seismicity region for the efficient reduction of earthquake damages. Recently, Korean engineers began to have interest in the seismic isolation or vibration control and applied it to some important structures such as LNG storage tanks, many bridges and several buildings. However, design codes are not defining such useful advanced technologies for the design of building structures and several projects employing seismic isolation or vibration control in the design of structures had difficulties in obtaining construction permit from the local government. Therefore, it is an urgent requirement to introduce these advanced technologies in the seismic design code.

Evaluation on the Maximum Yield Strength of Steel Stirrups in Reinforced Concrete Beams (철근콘크리트 보에 사용된 전단보강철근의 항복강도 제한에 대한 평가)

  • Lee, Jin-Eun;Lee, Jung-Yoon
    • Journal of the Korea Concrete Institute
    • /
    • v.24 no.6
    • /
    • pp.685-693
    • /
    • 2012
  • The yield strength of shear reinforcement is restricted in the present design codes. In this study, the possibility of the yield strength increase in shear reinforcement is evaluated according to ACI318-08, EC2-02 and CSA-04 by comparing the experimental and calculated results. Three cases were used to analyze the shear strength of the beam. One had no limitation in the yield strength of shear reinforcement, another had restriction on the yield strength of shear reinforcement, and the other had a restriction on the yield strength of shear reinforcement and the shear reinforcement ratio. The study results showed that the case with unlimited shear reinforcement yield strength predicted the test result better than other two cases. Even though the rebar yield strength higher than the strength required in present code was applied to existing shear design equation, the result was reasonable. Therefore, the design equation seemed to be appropriate even if the high-strength shear reinforcement is used in practice based on the existing shear design method.

Smoke Control Performance of a Serial Structure Using "CONTAM" (CONTAM을 이용한 직렬형태 구조의 제연성능 구현에 관한 연구)

  • Kim, Mi-Seon;Seo, Dong-Gil;Gu, Seon-Hwan;Yoo, Young-Min;Song, Young-Joo
    • Fire Science and Engineering
    • /
    • v.33 no.6
    • /
    • pp.53-62
    • /
    • 2019
  • A recent trend shows that more buildings are being constructed as mixed-use (residential and commercial) properties for efficient land use. This has led to an increased frequency in the occurrence of fires and the associated potential risks. In particular, in case of high-rise apartments, at least one of the elevators in each building is installed for evacuation purposes separately from the emergency elevator; therefore, for a combined ancillary room and emergency elevator platform situation, the structure is inevitably in series with the evacuation elevator platform. Thus, a proposal for a new type of ventilation zone based on existing national fire safety codes is required to achieve smoke control performance. To this end, the air egress velocity and differential pressure of each ventilation zone are checked using the "CONTAM" software; further, an alternative is proposed to secure smoke control performance for series structures.

Some Critical Problems in Seismic Design of High-Rise RC Building frame Systems (고층 RC 건물골조시스템의 내진설계상 몇 가지 주요 문제점)

  • Lee Han-Seon;Jeong Seong-Wook;Ko Dong-Woo
    • Journal of the Korea Concrete Institute
    • /
    • v.17 no.5 s.89
    • /
    • pp.727-734
    • /
    • 2005
  • High-rise residential buildings these days tend to adopt a building frame system as primary earthquake resisting structural system for some architectural reasons. But there exist several ambiguities in designing such building frame systems according to current codes with regards to : the effective stiffness property of RC cracked section in static and dynamic analyses, analytical model to evaluate story drift ratio, and deformation compatibility requirements of frames. The comparative study for these issues by appling KBC 2005 to a typical building frame system shows that demands of member strength and story drift ratio can be different significantly depending on engineer's Interpretation and application of code requirements. And a building frame system can be noneconomical, compared with the dual system, because of higher demands on strength or ductility in both frames and shear walls.

Modelling beam-to-column joints in seismic analysis of RC frames

  • Lima, Carmine;Martinelli, Enzo;Macorini, Lorenzo;Izzuddin, Bassam A.
    • Earthquakes and Structures
    • /
    • v.12 no.1
    • /
    • pp.119-133
    • /
    • 2017
  • Several theoretical and analytical formulations for the prediction of shear strength in reinforced concrete (RC) beam-to-column joints have been recently developed. Some of these predictive models are included in the most recent seismic codes and currently used in practical design. On the other hand, the influence of the stiffness and strength degradations in RC joints on the seismic performance of RC framed buildings has been only marginally studied, and it is generally neglected in practice-oriented seismic analysis. To investigate such influence, this paper proposes a numerical description for representing the cyclic response of RC exterior joints. This is then used in nonlinear numerical simulations of RC frames subjected to earthquake loading. According to the proposed strategy, RC joints are modelled using nonlinear rotational spring elements with strength and stiffness degradations and limited ductility under cyclic loading. The proposed joint model has been firstly calibrated against the results from experimental tests on 12 RC exterior joints. Subsequently, nonlinear static and dynamic analyses have been carried out on two-, three- and four-storey RC frames, which represent realistic existing structures designed according to old standards. The numerical results confirm that the global seismic response of the analysed RC frames is strongly affected by the hysteretic damage in the beam-to-column joints, which determines the failure mode of the frames. This highlights that neglecting the effects of joints damage may potentially lead to non-conservative seismic assessment of existing RC framed structures.

A Study on the Application of Fire Protection Facilities in Large Enclosure Gymnasium (대규모 실내경기장의 소방방재설비 적용현황 분석)

  • Choi, Dong-Ho;Kim, Choon-Dong;Yang, Jeong-Hoon;Cho, Young-Hum
    • Journal of Korean Association for Spatial Structures
    • /
    • v.10 no.2
    • /
    • pp.135-145
    • /
    • 2010
  • The objective of this study is to draw basic data for the application of the fire protection planning for the future plan large enclosure buildings in Korea through an analysis of its characteristics by case studies of the domestic and foreign large scale gymnasiums. In this study, domestic building codes for the fire protection are investigated and fire detection systems, fire extinguishing systems, smoke control systems and evacuation systems of three large scale gymnasiums located at Korea and eight foreign countries are compared and analyzed. The results of this study show that infrared light fire detection system and flame detector for spacial characteristics are potentially used in fire protection systems of large scale gymnasiums: dry type sprinkler and sprinkler water gun are adopted in fire detection system; and smoke accumulation system is widely utilized in smoke control system.

  • PDF

Seismic performance of lateral load resisting systems

  • Subramanian, K.;Velayutham, M.
    • Structural Engineering and Mechanics
    • /
    • v.51 no.3
    • /
    • pp.487-502
    • /
    • 2014
  • In buildings structures, the flexural stiffness reduction of beams and columns due to concrete cracking plays an important role in the nonlinear load-deformation response of reinforced concrete structures under service loads. Most Seismic Design Codes do not precise effective stiffness to be used in seismic analysis for structures of reinforced concrete elements, therefore uncracked section properties are usually considered in computing structural stiffness. But, uncracked stiffness will never be fully recovered during or after seismic response. In the present study, the effect of concrete cracking on the lateral response of structure has been taken into account. Totally 120 cases of 3 Dimensional Dynamic Analysis which considers the real and accidental torsional effects are performed using ETABS to determine the effective structural system across the height, which ensures the performance and the economic dimensions that achieve the saving in concrete and steel amounts thus achieve lower cost. The result findings exhibits that the dual system was the most efficient lateral load resisting system based on deflection criterion, as they yielded the least values of lateral displacements and inter-storey drifts. The shear wall system was the most economical lateral load resisting compared to moment resisting frame and dual system but they yielded the large values of lateral displacements in top storeys. Wall systems executes tremendous stiffness at the lower levels of the building, while moment frames typically restrain considerable deformations and provide significant energy dissipation under inelastic deformations at the upper levels. Cracking found to be more impact over moment resisting frames compared to the Shear wall systems. The behavior of various lateral load resisting systems with respect to time period, mode shapes, storey drift etc. are discussed in detail.

A Study on the Behavior of stress path subject to the gap size of metal touch connection (메탈터치 이음부의 틈의 크기에 따른 응력전달 거동에 대한 연구)

  • Hong, Kappyo;Kim, Seok Koo
    • Journal of Korean Society of Steel Construction
    • /
    • v.16 no.5 s.72
    • /
    • pp.599-607
    • /
    • 2004
  • As buildings become more high-rise and lightweight in recent years, steel has been utilized more frequently. Based on the American AISC standard, all axial loads could be carried through a bearing load in a column splice, but according to Korean codes, the bearing load has constrained the stress that could be carried by only 25% of all axial loads. Thus, new column splice methods that use metal touch have been examined. In this study, the stress path mechanism, as an intermediation parameter in the gap's magnitude, must be determined. Similarly, the behavioral aspect of the metal touch connection must be sought after comparing and analyzing the results of the test.

A Study on the Behavior of Metal Touch Connection subject to Connection Types (이음방식 및 틈의 위치에 따른 메탈터치 이음부의 거동에 관한 연구)

  • Hong, Kap Pyo;Kim, Seok Koo
    • Journal of Korean Society of Steel Construction
    • /
    • v.16 no.5 s.72
    • /
    • pp.661-669
    • /
    • 2004
  • In the steel structure of high-rise buildings, a connection analysisand a column design have been made after welding and bolting suitable gaps. Each country, however, has different codes, and such differences are very big. American steel has been designed according to a code that all axial loads can be carried from the upper parts to the lower parts as determined by the designer, but Korean and Japanese steel have been designed by 1/4 of the standard of all axial loads. In this paper, a metal touch experiment was done as an intermediation parameter with a connecting location and a connecting method for economic and constructive efficiency. Every specimen is tested by a low-to-high displacement control to grasp ultimate strength, displacement, the connection's lateral deflection, and stress. The results of the test were compared and analyzed.