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Prediction of the Minimum Required Pressure of Soundless Chemical Demolition Agents for Plain Concrete Demolition

무근콘크리트 해체시 무소음화학팽창제의 최소요구팽창압 예측

  • Kim, Kyeongjin (Department of Civil and Environmental Engineering, Korea Maritime and Ocean University) ;
  • Cho, Hwangki (Department of Mechanical Engineering, Korea Maritime and Ocean University) ;
  • Sohn, Dongwoo (Department of Mechanical Engineering, Korea Maritime and Ocean University) ;
  • Koo, Jaehyun (Hanyang EMC) ;
  • Lee, Jaeha (Department of Civil Engineering, Korea Maritime and Ocean University)
  • 김경진 (한국해양대학교 토목환경공학과) ;
  • 조황기 (한국해양대학교 기계공학과) ;
  • 손동우 (한국해양대학교 기계공학과) ;
  • 구재현 ((주)한양이엠씨) ;
  • 이재하 (한국해양대학교 건설공학과)
  • Received : 2018.06.29
  • Accepted : 2018.09.03
  • Published : 2018.10.31

Abstract

In construction site, conventional methods such as jackhammer or explosive methods(dynamite) have been often used for the demolition of structures. Use of those methods are more carefully treated in environmentally and historically sensitive area. For those reasons, use of Soundless Chemical Demolition Agent(SCDA) is getting the spotlight. The SCDA is a powder which has expansive strength when it is mixed with water. In these Characteristics, SCDA can destroy the concrete or rock as it is poured into boreholes of the concrete or rock structures. However, there is no industrial standard for the use of SCDA effectively yet. In this study, experimental study to measure the expansive pressure was conducted depending on various boundary conditions such as waterproof, length of the steel pipe, submerged of steel pipe. Furthermore, computational analysis using damage plasticity model to predict the minimum required pressure of the SCDA for the concrete demolition depending on spacing between holes(k-factor) and compressive strength of the concrete was conducted. Obtained results indicates that water heat dissipation with submerged steel pipe shows the stable pressure for measuring the SCDA and hole distance(k-factor) is the most important factor for crack initiation of concrete.

도심지나 문화재가 인접한 지역 등의 소음, 진동 등 기존 발파해체 공법이 제한적인 조건에서 사용할 수 있는 구조물 해체공법으로 무소음화학팽창제(soundless chemical demolition agent, SCDA)를 이용한 공법이 있다. 그러나 SCDA의 사용에 대한 기준이나 가이드라인에 참고될 만한 연구는 미미한 실정이다. 이 연구에서는 실내실험을 수행하여 강관의 길이, 외부수분차단, 수화열 발산 등의 다양한 조건에 따른 SCDA의 팽창압 발현 특성을 확인하였다. 또한 SCDA의 최소요구팽창압 예측을 위한 해석모델(자유단 1면, 고정단 3면의 직사각형 모델)을 개발하고 주요변수해석(홀 간 거리, 콘크리트 압축강도)을 수행하였다. 이 연구의 해석결과를 활용하여 자유단으로부터 콘크리트 구조물의 박락을 효과적으로 유도할 수 있을 것으로 판단된다.

Keywords

References

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