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Behavior of Model Pile Embedded in Expansive Soil with Magnesia Oxide-Based Refractories

MgO계 내화물이 함유된 팽창성 지반에서의 모형말뚝 거동 분석

  • Yoon, Boyoung (Sch. of Civil, Environmental and Architectural Engrg., Korea Univ.) ;
  • Kim, Mintae (Sch. of Civil, Environmental and Architectural Engrg., Korea Univ.)
  • 윤보영 (고려대학교 건축사회환경공학부) ;
  • 김민태 (고려대학교 건축사회환경공학부)
  • Received : 2023.10.04
  • Accepted : 2023.10.18
  • Published : 2023.11.30

Abstract

This study explores the performance of pile foundations in highly expansive soil, incorporating magnesium oxide-based refractory materials. A controlled model chamber, housing a fixed pile, was utilized to induce ground expansion through fused magnesia (FM). The investigation focused on measuring the vertical displacement of FM-sand mixtures and the axial load on the pile in relation to depth and time. The study varied the amount of FM content (FMc) at 30%, 50%, and 70%. The upward movement exhibited an augmentation with increasing FMc, tapering off with depth as accumulation progressed toward the mixture surface. Compression and tensile forces were both evident along the pile for FMc at 30% and 50%, while only a tensile force was observed at an FMc of 70%. These results offer valuable insights for the analysis of pile behavior within FM-sand mixtures.

본 연구에서는 산화마그네슘계 내화물(Magnesium oxide-based refractory)을 함유한 팽창성 지반에서의 말뚝기초 거동을 분석하였다. 고정단 말뚝이 설치된 모형토조에 용융마그네시아(Fused magnesia, FM)를 활용하여 지반의 융기를 유도하였으며, FM함유량(FMc = 30%, 50%, 70%)을 변화하여 시간에 따른 깊이별 융기량과 말뚝의 축력을 분석하였다. FMc가 증가할수록 더 큰 융기량이 측정되었으며, 시료의 표면으로 갈수록 융기량이 누적되어 깊이에 따라 융기량이 감소하였다. 그러나 깊이별 융기율의 차이와 그에 따른 팽창압의 차이로 인하여 FMc = 30%와 50%일때 말뚝에 뚜렷한 압축력과 인장력이 발현되었으며, FMc = 70%일 때에는 말뚝 전체에 인장력만이 발현되었다. 이런한 결과는 산화마그네슘계 내화물이 포함된 혼합토 내의 말뚝거동을 분석하는데 중요한 자료로 활용할 수 있을 것으로 판단된다.

Keywords

Acknowledgement

본 연구는 과학기술정보통신부의 재원으로 한국연구재단의 지원을 받아 수행된 연구입니다(No2021R1A2C1010281).

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