• Title/Summary/Keyword: construction loads

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Dynamic Analysis of Concrete Rigid Barriers by Computer Simulation (컴퓨터 시뮬레이션에 의한 콘크리트 교량난간의 동적거동 분석)

  • 김재일;안재석;박진환;우광성
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2004.04a
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    • pp.217-224
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    • 2004
  • This paper proposed a new impact equation by analyzing the form of the proposal section 1 and section 2 proposed by Korea Highway Corporation, F-type, NJ-type and SS-type with HVOSM program Because the impact equation proposed by Ministry Construction & Transportation(1992) considered an only impact velocity, the values of impact loads calculated by HVOSM program are 21.5∼44 times as large as those using equation of MCT. The values of HVOSM program are 1.4 times as large as those of Olson's model because Olson's equation consider impact vehicle, impact velocity and impact angle. But, it does not consider geometric characters, while HVOSM program considers characters. Considering the shapes of sections and the conditions of colliding, HVOSM program can calculate imuact load. As Multiple Regression Analysis is conducted with the calculated values, the R² values of the proposed equations are 0.984 in SB1∼SB3 and 0.958 in SB4∼SB6. After all, the equation proposed in this study have better results than Olson's equation.

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Optimal Displacement Control of Shear Wall Structure using Sensitivity Analysis Technique (감도해석기법을 이용한 전단벽 구조물의 최적변위제어)

  • Lee Han-Joo;Jung Sung-Jin;Kim Ho-Soo
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2005.04a
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    • pp.121-128
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    • 2005
  • This study presents an effective stiffness-based optimal technique to control quantitatively lateral drift for shear wall structures subject to lateral loads. To this end the displacement sensitivity depending on behavior characteristics of shear wall structures is established. Also, the approximation concept that can preserve the generality of the mathematical programming and can efficiently solve large scale problems is introduced. Resizing sections in the stiffness-based optimal design are assumed to be uniformly varying in size and the technique of member grouping is considered for the improvement of construction efficiency Two types of 11-story shear wall structures are presented to illustrate the features of the quantitative lateral drift control technique proposed in this study.

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Analytical study for effects of shoring stiffness and slab cracking on construction loads of flat plates (플랫 플레이트 시공하중에 대한 동바리 강성 및 슬래브 균열 효과 분석)

  • Kim, Jae-Yo;Hwang, Hyeon-Jong;Park, Hong-Gun;Hong, Geon-Ho;Lim, Joo-Hyuk;Kim, Yong-Nam
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2009.04a
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    • pp.438-441
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    • 2009
  • 휨강성이 작은 바닥시스템인 플랫 플레이트 구조는 응력조건 뿐만 아니라 사용성조건에 의하여 구조적 성능이 결정될 수 있으며, 특히 과도한 시공 하중의 작용은 시공 중 안전성에 대한 단기적인 손상 뿐만 아니라 사용성에 관련된 장기적인 손상을 발생시킬 수 있다. 이러한 플랫 플레이트의 시공하중은 동바리지지 층 수, 시공주기, 슬래브 콘크리트의 재료적인 강성 뿐만 아니라, 동바리의 강성과 슬래브에 발생하는 균열에 의한 영향에 의하여 결정된다. 본 논문에서는 다양한 설계조건에 대한 해석연구를 통하여, 동바리-슬래브의 강성비 변화 및 콘크리트 균열에 의한 단면강성저하가 슬래브들 간의 하중 분포에 미치는 영향을 분석하고, 이러한 동바리 강성 및 슬래브 균열의 영향을 고려한 시공하중 산정법을 제안한다.

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Curtain Wall Façades on the New Generation of Supertall Buildings Present and Future Directions

  • Oh, Sae Hwang
    • International Journal of High-Rise Buildings
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    • v.9 no.2
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    • pp.113-125
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    • 2020
  • Beginning in the late 19th century, construction of skyscrapers spread throughout Chicago, New York City, and then the world as demand of space in buildings and increase of cost of land. With this change curtain wall systems have evolved to be more visually complex; these unique profiles of the skyscraper became powerful images and symbols of our cities. A curtain wall is defined as usually aluminum-framed wall containing in-fills of glass and metal panels. The framing is attached to the building structure and does not carry the floor or roof loads of the building.

Numerical investigation on scale-dependent vibrations of porous foam plates under dynamic loads

  • Fenjan, Raad M.;Ahmed, Ridha A.;Faleh, Nadhim M.;Fatima, Fatima Masood
    • Structural Monitoring and Maintenance
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    • v.7 no.2
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    • pp.85-107
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    • 2020
  • Dynamic responses of porous piezoelectric and metal foam nano-size plates have been examined via a four variables plate formulation. Diverse pore dispersions named uniform, symmetric and asymmetric have been selected. The piezoelectric nano-size plate is subjected to an external electrical voltage. Nonlocal strain gradient theory (NSGT) which includes two scale factors has been utilized to provide size-dependent model of foam nanoplate. The presented plate formulation verifies the shear deformations impacts and it gives fewer number of field components compared to first-order plate model. Hamilton's principle has been utilized for deriving the governing equations. Achieved results by differential quadrature (DQ) method have been verified with those reported in previous studies. The influences of nonlocal factor, strain gradients, electrical voltage, dynamical load frequency and pore type on forced responses of metal and piezoelectric foam nano-size plates have been researched.

A study for the structural design of floating airports on sea (부유식 해상공항의 구조설계에 관한 연구)

  • Seong-Whan Park;Tae-Young Chung
    • Journal of the Society of Naval Architects of Korea
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    • v.38 no.2
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    • pp.19-25
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    • 2001
  • Structural design requirements for very large floating structures(VLFS) are different corresponding to this purpose and structural type. In this study, the structural design procedure of VLFS is described, composing of the following processes : construction of design conditions. choice of structural types and main materials, estimation of structural design loads, determination of structural arrangements, and scantling of structural members. As an example of practical application, the initial structural design of floating airport and container terminal for Pusan is demonstrated.

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A Case Study on the Reinforcement Method of Subway Tunnel (도심지 지하철 터널의 지반보강공법 시공사례 연구)

  • 천병식;여유현;최현석
    • Proceedings of the Korean Geotechical Society Conference
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    • 1999.10a
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    • pp.201-208
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    • 1999
  • The NATM(New Austrian Tunnelling Method) has been used for tunnelling since 1980's. But Collapses of tunnel under construction take place frequently, especially at urban areas because of adjacent buildings, underground conduits and traffic loads. This paper is a case study on the reinforcement method of subway tunnel at urban areas. In this study, ground inspection, geological investigation, laboratory test and numerical analysis by means of FDM program were carried out. The tunnel excavation was stopped because of over excessive brake of tunnel crown and shotcrete was installed to prevent deformation of adjacent ground as the temporary method. From the result of field survey and geological investigation, it is found that the soft weathered soil was distributed to the ground of tunnel invert unlike original investigation. The results of the analysis and the study show that the SGR(Space Grouting Rocket) method and Umbrella method can be applied for the stability of tunnel excavation and in addition the reinforcement of concrete lining is required for long-term stability of tunnel.

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Shear Load Transfer Characteristics of Drilled Shafts in Weathered Rocks (풍화암에 근입된 현장타설 말뚝의 하중 전이 특성)

  • Jeong, Sang-Seom;Cho, Sung-Han;Kim, Soo-Il
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.03a
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    • pp.85-106
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    • 2000
  • The load distribution and deformation of drilled shafts subjected to axial loads were evaluated by a load transfer approach. The emphasis was on quantifying the load transfer mechanism at the interface between the shafts and surrounding highly weathered rocks based on a numerical analysis and small-scale tension load tests performed on nine instrumented piles. An analytical method that takes into account the soil coupling effect was developed using a modified Mindlin's point load solution. Based on the analysis, a single-modified hyperbolic model is proposed for the shear transfer function of drilled shafts in highly weathered rocks. Through comparisons with field case studies, it is found that the prediction by the present approach is in good agreement with the general trend observed by in-situ measurements.

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Study on the determination of optimum size of storage tank and intercepting capacity for CSOs reduction in urban area (도시지역 CSOs 저감을 위한 저류조 및 이송관로의 최적 용량결정에 관한 연구)

  • Lee, Kwan Yong;Choi, Won Suk;Lee, Yong Jae;Koo, Won Suk;Song, Chang Soo
    • Journal of Korean Society of Water and Wastewater
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    • v.26 no.6
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    • pp.735-745
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    • 2012
  • Storage method is one of major measures for reduction of CSOs pollutant loads and several projects have been done nationwide. But systematic analysis of intercepting capacity has not been studied to determine optimum size of storage facility. In this research, not only storage volume but also intercepting capacity which means flow capacity from intercepting facility to CSOs storage facility was studied and optimum sizing method for storage facility was proposed. The result shows that pollutants reduction efficiency can be increased significantly by increasing intercepting capacity and it might reduce storage volume and total construction costs. Intercepting capacity for the study area was evaluated and it was shown as equivalent to 83 % probability rainfall intensity.

The Analysis of Inground LNG Storage Tank Compression Ring Behavior during Concrete Pouring (콘크리트 타설에 따른 지하식 LNG 저장탱크 컴프레션 링 거동 분석)

  • Kim Y.K.;Kim J.H.;Yoon I.S.;Oh B.T.;Yang Y.M.
    • 한국가스학회:학술대회논문집
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    • 2004.11a
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    • pp.82-87
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    • 2004
  • Compression ring is a part of LNG storage tank. The main function of the compression ring is connected the roof plate with concrete side wall. End of its one side is embedded in the side concrete wall and the other's connected with the roof plate by welding. It is designed to support stably for all the loads such as self weight of steel roof, inner pressure and concrete weight. We fulfill the FEM analysis to analysis the compression ring behavior during construction. Also we studied the effect of the change of design variables. On the basis of the results, we could introduce a more reasonable design method for compression ring.

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