한국지반신소재학회논문집 (Journal of the Korean Geosynthetics Society)

  • 제22권1호
  • /
  • Pages.87-96
  • /
  • 2023
  • /
  • 2508-2876(pISSN)
  • /
  • 2287-9528(eISSN)
한국지반신소재학회 (Korean Geosynthetics Society)
권호 표지
DOI QR코드

DOI QR Code

대심도 준설 매립지반에서의 층별침하 계측관리에 관한 사례 연구

Instrumentation Management of Differential Settlement of the Deep Soft Ground with Dredged Clay Reclaimed in the Upper

  • 투고 : 2023.01.31
  • 심사 : 2023.03.24
  • 발행 : 2023.03.30
PDF 다운로드
⟨ 이전 논문 다음 논문 ⟩

초록

상부에 준설매립점토층이 존재하고 점토층이 두껍게 분포되어 있는 부산항 신항만에서 측정된 지표침하 값과 층별침하 값은 많은 차이가 있다. 이런 결과의 원인과 해결방안을 찾기 위하여 연약지반 개량에 사용된 층별침하계의 실태, 층별침하계 형식별 특성, 설치방법, 계측 빈도, 계측데이터 관리방안, 결과의 정리 및 분석 등에 대해 고찰해 보았다. 대변형이 발생하는 대심도 연약지반 개량공사에서 스크류타입의 층별침하계의 경우 휨 변형이 다른 형식의 계측기에 비해 적어 망실의 우려도 적고 각 지층별로 천공하여 계측기를 설치하므로 데이터의 신뢰도도 상대적으로 높다. 정도 높은 침하계측 자료의 양이 많을수록 침하분석 정밀도는 높아지므로 표준시방서에서 제시한 계측빈도보다 기준을 강화하여 관리가 필요하다. 층별침하계 계측데이터의 관리는 측점별 지표침하량, 층별침하량, 간극수압계 침하량과 같이 해당 구간의 침하량과 성토고의 경시 그래프 작성하여 관리하는 것이 바람직하다. 침하분석은 압축특성이 다른 다층지반일 경우 층별침하 데이터를 이용하여 각 지층별 압밀특성을 각각 산정하여 침하분석이 이루어지는 게 더 타당하다.

There are a lot of difference between the surface settlement and the differential settlement measured at the Busan New Port, where the dredged and reclaimed clay layer exists and below the clay is originally thickly distributed. To find the cause and solution of this, the actual conditions of each differential settlement used for the soft ground improvement, characteristics, installation method, measurement frequency, measurement data management, and data analysis of each type were considered. In the deep soft ground improvement work where large deformation occurs, the bending deformation of the screw-type differential settlement gauge is less than that of other types of measuring instruments, so there is less risk of loss, and the reliability of data is relatively high as the instruments are installed by drilling for each stratum. Since the greater the amount of high-precision settlement measurement data, the higher the settlement analysis precision. It is necessary to manage with higher criteria than the measurement frequency suggested in the standard specification. For the data management of the differential settlement gauge, it is desirable to create graphs of the settlement and embankment height of the relevant section over time, such as surface, differential, and settlement of pore water pressure gauge for each point. In the case of multi-layered ground with different compression characteristics, it is more appropriate to perform settlement analysis by calculating the consolidation characteristics of each stratum using a differential settlement data.

키워드

과제정보

This study is the result of the support from the Busan Port Construction Office of the Busan Regional Office of Oceans and Fisheries of Ministry of Oceans and Fisheries, "Research Service for Ground Performance Improvement in Busan Port and Jinhae New Port". (Project Number: 202204047CD-00)

참고문헌

  1. Bjerrum, L. (1967), "Engineering geology of norwegian normally-consolidated marine clays as related to settlement of buildings", Geotechnique, pp.17-83.
  2. Busan Port Authority (2021), Design and construction of soft ground improvement work and maintenance manual.
  3. Jang, J. G. (2020), A study on the application of settlement prediction method according to field Conditions at the field of soft ground, Ph.D. Thesis, Pusan Nation University.
  4. Kang, S. C. (2021), "A study on the evaluation method of undrained shear strength using settlement measurement data, Ph.D. thesis, Dong Eui University.
  5. Kim, J. H., Kang, S. H. and Kim, T. H. (2015), "Settlement prediction for staged filling construction on the PVD-improved soft ground using SPSFC method", Procedia Earth and Planetary Science, Vol.15, pp.146-151. https://doi.org/10.1016/j.proeps.2015.08.036
  6. Kim, J. M. (2019), A case study on the prediction of final consolidation settlement analysis considering the results of soft ground instrumentation in Busan, Master thesis, Pukyong National University
  7. Korean Society of Civil Engineers (2019), Research service on the cause of settlement and long-term settlement prediction at the Ung-dong hinterland of Busan New Port.
  8. Lee, S. W., Jee S. H., Yoo, S. J. and Lee, Y. N. (2000), "Sedimentation and consolidation behavior of dredged clay fill", Journal of Korean Geotechnical Society, Vol.16, No.4, pp.149-156.
  9. Ministry of Land, Infrastructure and Transport (2018a), Korean Design Standard : Ground measurement, KDS 11 1015, MOLIT.
  10. Ministry of Land, Infrastructure and Transport (2018b), Korean Construction Specification : Ground measurement during construction, KDS 11 10 15, MOLIT.
  11. Ministry of Oceans and Fisheries (2016), Port and fishing port design standards.
  12. Ministry of Oceans and Fisheries (2018), Port and fishing port standard specifications.
  13. Nomura, S., Ikeda, T., Katagiri, M. and Terachi, M. (2008), "Consolidation settlement prediction of reclaimed land with dredged clay case record of Kita-Kyushu airport", Journal of the Japanese Geotechnical Society, Vol.56, No.9, pp.10-13.