• 제목/요약/키워드: Concrete ground

검색결과 1,323건 처리시간 0.031초

Collapse fragility analysis of the soil nail walls with shotcrete concrete layers

  • Bayat, Mahmoud;Emadi, Amin;Kosariyeh, Amir Homayoun;Kia, Mehdi;Bayat, Mahdi
    • Computers and Concrete
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    • 제29권 5호
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    • pp.279-283
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    • 2022
  • The seismic analytic collapse fragility of soil nail wall structures with a shotcrete concrete covering is investigated in this paper. The finite element modeling process has been well described. The fragility function evaluates the link between ground motion intensities and the likelihood of reaching a specific level of damage. The soil nail wall has been subjected to incremental dynamic analysis (IDA) from medium to strong ground vibrations. The nonlinear dynamic analysis of the soil nail wall uses a set of 20 earthquake ground motions with varying PGAs. PGD is utilized as an intensity measure, the numerical findings demonstrate that the soil nailing wall reaction is particularly sensitive to earthquake intensity measure (IM).

PHC 파일 기초를 이용한 지중 열교환기 개발 및 성능 평가 (Development & Performance Evaluation of Ground Heat Exchanger Utilizing PHC Pile Foundation of Building)

  • 유형규
    • 한국태양에너지학회 논문집
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    • 제28권5호
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    • pp.56-64
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    • 2008
  • The objective of this study is to develope ground heat exchanger using PHC file used to building foundation, and it's element technology. So we construct PHC ground heat exchanger in the apartment house's PHC foundation and evaluate it's performance. First, we study PHC file type, heat exchanger pipe, grouting materials, and present apartment house's foundation condition for PHC ground heat exchanger and design it's proto type. Second according to grouting materials, we estimate construction convenience, and it's performance. Construction convenience side, PB 22 A pipe and sand grouting with moisture was good for PHC ground heat exchanger elements. Experiment result is very superior. Thermal conductivity B, C type(sand, gravel) was respectively 32.4 W/m$^{\circ}C$, 36.5 W/m$^{\circ}C$, D(concrete) Type 27.8 W/m$^{\circ}C$, E(bentonite) Type 19.6 W/m$^{\circ}C$. Thermal interference for 4 day experiment period in 3.8 m was very small. So PHC file is good for using ground heat exchanger.

Seismic characteristics of a Π-shaped 4-story RC structure with open ground floor

  • Karabini, Martha A.;Karabinis, Athanasios J.;Karayannis, Chris G.
    • Earthquakes and Structures
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    • 제22권4호
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    • pp.345-353
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    • 2022
  • The configuration of an open ground floor (pilotis) is a common and very critical irregularity observed in multistory reinforced concrete frame structures. The characteristics and the geometrical formation of the beams of the first story proved to be a critical parameter for the overall seismic behavior of this type of Reinforced Concrete (RC) structures. In this work the combination of open ground floor (pilotis) morphology with very strong perimetrical beams at the level of the first story is studied. The observation of the seismic damages and the in situ measurements of the fundamental period of four buildings with this morphology and Π-shaped plan view are presented herein. Further analytical results of a pilotis type Π-shaped RC structure are also included in the study. From the measurements and the analytical results yield that the open ground floor configuration greatly influences the fundamental period whereas this morphology in combination with strong beams can lead to severe local shear damages in the columns of the ground floor. The structural damage was limited in the columns of the ground floor and yet based on the changes of the in situ measured fundamental period the damaged level is assessed as DI=88%. Furthermore, due to the Π-shape of the plan view the tendency of the parts of the building to move independently strongly influences the distribution of the damages over the ground floor vertical elements.