• Title/Summary/Keyword: pre-stressing force

Search Result 14, Processing Time 0.022 seconds

Structural behavior of the suspen-dome structures and the cable dome structures with sliding cable joints

  • Liu, Hongbo;Chen, Zhihua
    • Structural Engineering and Mechanics
    • /
    • v.43 no.1
    • /
    • pp.53-70
    • /
    • 2012
  • Sliding cable joints have been developed for the cable dome structures and the suspen-dome structures to reduce the cable pre-stressing loss and obtain a uniform inner force in each hoop cable. However, the relevant investigation is less addressed on the structural behavior of the cable dome structures and the suspen-dome structures with sliding cable joints due to the lack of analysis techniques. In this paper, a closed sliding polygonal cable element was established to analyze the structural behavior of the cable dome structures and the suspen-dome structures with sliding cable joints. The structural behaviors with sliding cable joints were obtained.

Assessment of the Internal Pressure Fragility of the PWR Containment Building Using a Nonlinear Finite Element Analysis (비선형 유한요소 해석을 이용한 PWR 격납건물의 내압 취약도 평가)

  • Hahm, Daegi;Park, Hyung-Kui;Choi, In-Kil
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.27 no.2
    • /
    • pp.103-111
    • /
    • 2014
  • In this study, the probabilistic internal pressure fragility analysis was performed by using the non-linear finite element analysis method. The target structure is one of the containment buildings of typical domestic pressurized water reactors(PWRs). The 3-dimensional finite element model of the containment building was developed with considering the large equipment hatches. To consider uncertainties in the material properties and structural capacities, we performed the sensitivity analysis of the ultimate pressure capacity with respect to the variation of four important uncertain parameters. The results of the sensitivity analysis were used to the selection of the probabilistic variables and the determination of their probabilistic parameters. To reflect the present condition of the tendon pre-stressing force, the data of the pre-stressing force acquired from the in-service inspections of tendon forces were used for the determination of the median value. Two failure modes(leak, rupture) were considered and their limit states were defined to assess the internal pressure fragility of target containment building. The internal pressure fragilities for each failure mode were evaluated in terms of median internal pressure capacity, high confidence low probability of failure(HCLPF) capacity, and fragility curves with respect to the confidence levels. The HCLPF capacity was 115.9 psig for leak failure mode, and 125.0 psig for rupture failure mode.

An Experimental Study on the Flexural Behavior of Prestressed Composite Double T-Beams (프리스트레스트 강합성 Double T-Beam의 휨거동 특성에 관한 실험적 연구)

  • Hong, Sung-Nam;Kim, Kwang-Soo;Han, Kyung-Bong;Park, Sun-Kyu;Yoo, Byoung-Eok
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.11 no.1
    • /
    • pp.49-56
    • /
    • 2007
  • The existing Double T-Beams have been positively constructed in America and Europe due to their elegant appearance and simple section shapes. However, there are some problems; thery are relatively weak in the structural resistance, and need to use somewhat limited and complicated construction methods. In this paper, new composite beams made of concrete and steel are proposed, by taking adventage of their merits in an effort to solve thess controversial problems. In addition, feasibility is presented in developing composite Double T-Beams by introducing pre-stressing forces as well to enhance structural safety.

Prestressing Loss Management for PSC Girder Tendon Based on EM Sensing (EM센서를 활용한 PSC 텐던 긴장력 손실 관리)

  • Kim, Junkyeong;Park, Jooyoung;Zhang, Aoqi;Lee, Hwanwoo;Park, Seunghee
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • v.28 no.4
    • /
    • pp.369-374
    • /
    • 2015
  • In this paper, an EM sensing based prestressing force estimation method is proposed, in which it can estimate tensile force of PS tendon for PSC girder. The PSC girder has more improved performance than the general concrete girder by introducing the prestressing to the concrete. Thus the PSC girder bridge is widely constructed due to its high performance and low cost. However, the prestressing force has not been managed nevertheless it is major factor for the maintenance of the PSC girder bridge. The prestressing force was just measured during construction using jacking device and after that, it can not be managed. For this reason, this paper proposes a tensile force estimation method of PS tendon based on EM sensor. The permeability of ferroelectric material is changed according to the induced stress to the material, in which it can be measured using EM sensor. To measure the permeability of PS tendon, the EM sensor was fabricated and verified by performing the MTS test. The test was performed using 7-wire steel tendon under the 0, 40, 80, 120, 160, 200 KN of tensile force. The permeability of PS tendon was gradually decreased according to the increasement of tensile force. The regression method was used to find the relation between permeability and stress. As a result, the permeability has linear relation with the tensile force of PS tendon and the pre-stressing force can be estimated by the derived estimation equation.