• 제목/요약/키워드: pseudostatic test

검색결과 4건 처리시간 0.018초

사면의 안전율과 임계변위에 의한 지진 재해 위험지도의 비교 (Seismic Landslide Hazard Maps Based on Factor of Safety and Critical Displacements of Slope)

  • 정의송;조성원;김명모
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2001년도 봄 학술발표회 논문집
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    • pp.509-516
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    • 2001
  • As the first step for the application of seismic landslide hazard maps to domestic cases, two types of hazard maps on Ul-joo from pseudostatic analysis and Newmark sliding block analysis are constructed and comllared. Arcview, the GIS program and the 1:5,000 digital maps of the test-site are used for the construction of hazard maps and tile parameters for the analyses are determined by seismic survey and laboratory tests. The results from the pseudostatic analysis have more conservative values of lower critical slope angles, although the results from the two different analyses have similar tendencies. In detail, with increasing the peak ground acceleration, the difference between the two analyses in the critical slope angle increases, while the difference decreases with increasing the maximum soil depth.

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Hybrid simulation tests of high-strength steel composite K-eccentrically braced frames with spatial substructure

  • Li, Tengfei;Su, Mingzhou;Guo, Jiangran
    • Steel and Composite Structures
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    • 제38권4호
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    • pp.381-397
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    • 2021
  • Based on the spatial substructure hybrid simulation test (SHST) method, the seismic performance of a high-strength steel composite K-eccentrically braced frame (K-HSS-EBF) structure system is studied. First, on the basis of the existing pseudostatic experiments, a numerical model corresponding to the experimental model was established using OpenSees, which mainly simulated the shear effect of the shear links. A three-story and five-span spatial K-HSS-EBF was taken as the prototype, and SHST was performed with a half-scale SHST model. According to the test results, the validity of the SHST model was verified, and the main seismic performance indexes of the experimental substructure under different seismic waves were studied. The results show that the hybrid simulation results are basically consistent with the numerical simulation results of the global structure. The deformation of each story is mainly concentrated in the web of the shear link owing to shear deformation. The maximum interstory drifts of the model structure during Strength Level Earthquake (SLE) and Maximum Considered Earthquake (MCE) meet the demands of interstory limitations in the Chinese seismic design code of buildings. In conclusion, the seismic response characteristics of the K-HSS-EBFs are successfully simulated using the spatial SHST, which shows that the K-HSS-EBFs have good seismic performance.

Cyclic tests on RC joints retrofitted with pre-stressed steel strips and bonded steel plates

  • Yu, Yunlong;Yang, Yong;Xue, Yicong;Wang, Niannian;Liu, Yaping
    • Structural Engineering and Mechanics
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    • 제75권6호
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    • pp.675-684
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    • 2020
  • An innovative retrofit method using pre-stressed steel strips and externally-bonded steel plates was presented in this paper. With the aim of exploring the seismic performance of the retrofitted RC interior joints, four 1/2-scale retrofitted joint specimens together with one control specimen were designed and subjected to constant axial compression and cyclic loading, with the main test parameters being the volume of steel strips and the existence of externally-bonded steel plates. The damage mechanism, force-displacement hysteretic response, force-displacement envelop curve, energy dissipation and displacement ductility ratio were analyzed to investigate the cyclic behavior of the retrofitted joints. The test results indicated that all the test specimens suffered a typical shear failure at the joint core, and the application of externally-bonded steel plates and that of pre-stressed steel strips could effectively increase the lateral capacity and deformability of the deficient RC interior joints, respectively. The best cyclic behavior could be found in the deficient RC interior joint retrofitted using both externally-bonded steel plates and pre-stressed steel strips due to the increased lateral capacity, displacement ductility and energy dissipation. Finally, based on the test results and the softened strut and tie model, a theoretical model for determining the shear capacity of the retrofitted specimens was proposed and validated.

공진주/비틂 전단(RC/TS)시험기를 이용한 건조 사질토의 변형특성 (Deformational Characteristics of Dry Sand Using Resonant Column / Torsional Shear Testing Equipment)

  • 김동수
    • 한국지반공학회지:지반
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    • 제11권1호
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    • pp.101-112
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    • 1995
  • 동적하중을 받는 지반-구조물 시스템의 설계를 위해 전단탄성계수와 감쇠비로 표현되는 지반의 변형특성의 결정은 매우 중요하다. 본 논문에서는 공진주/비틂전단시험기를 이용하여 저변형률 및 중간 변형률하에서 건조사질토의 변형특성을 연구하였다. 동적시험인 공진주시험과 반복시험인 비틀전단시험을 동일한 공시 체를 이용하여 실시하였다. 진동측정시스템을 개량하여 응력 -변형관계가 하중반복회수와 전단변형률의 크기에 영향을 받지않는 선형영역을 찾았으며 이 영역에서 이력감쇠가 존재함을 나타내었다. 반복한계변형률 이상에서는 하중반복회수에 따라 전단탄성계수는 증가하고 감쇠비는 감소하였다. 사질토의 전단탄성계수와 감쇠비는 진동주파수에 영향을 받지 않으며 의사정적시험인 비틈전단시험에서 변형특성과 동적시험인 공진주 시험에서 얻은 값은 비교시 하중반복회수의 영향을 고려하면 동일하다. 그러므로 공진주l비틀전단시 험을 통해 얻은 변형특성은 지반-구조물시스템의 동적해석은 물론 정적해석에서도 적용할 수 있다.

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