• Title/Summary/Keyword: 제트 그라우팅 공법

Search Result 4, Processing Time 0.016 seconds

A Field Study on the Constructability and Performance Evaluation of Waveform Micropile (현장시험을 통한 파형 마이크로파일의 시공성 및 거동 평가)

  • Jang, Young-Eun;Han, Jin-Tae
    • Journal of the Korean Geotechnical Society
    • /
    • v.32 no.10
    • /
    • pp.67-79
    • /
    • 2016
  • Waveform micropile is an advanced construction method that combined the concept of conventional micropile with jet grouting method. This new form of micropile was developed to improve frictional resistance, which consequently leads to achieving higher bearing capacity and cost efficiency. Two field tests were conducted to examine the field applicability as well as to verify the effects of bearing capacity enhancement. In particular, waveform micropile construction using jet grouting method was performed to evaluate the viability of waveform micropile installation. After testing, the surrounding ground was excavated to check the accomplishment on the shape of waveform micropile. The result showed that waveform micropile can be installed by adjusting the grouting time and pressure. In the loading tests, waveform micropile's bearing capacity increased by 1.4 to 2.3 times depending on their shapes when compared with conventional micropile. Overall results clearly demonstrated that waveform micropile is an enhanced construction method that can improve bearing capacity.

Performance Evaluation of Waveform Micropile with Different Shapes by Centrifuge Test (원심모형실험을 이용한 파형 마이크로파일 형상에 따른 성능평가)

  • Jang, Young-Eun;Han, Jin-Tae
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.36 no.6
    • /
    • pp.1049-1057
    • /
    • 2016
  • The waveform micropile is a type of foundation that has a single or multiple shear keys on the pile shaft, and it is constructed through a jet grouting method as a way to increase the shaft resistance of the bonded area between the pile and the soil. In this paper, a geotechnical centrifuge test was performed to study the axial performance of the waveform micropile from other models. The six test models consisted of three waveform micropiles with a single shear key at three different depths, a waveform micropile with multiple shear keys, a conventional micropile, and a jet grouting micropile. Based on the test results, it was clearly shown that the waveform micropile increased in its bearing capacity compared to the other models without the shear key. Additionally, it was observed that the confining pressure for the location of a shear key is directly related to the increase of the bearing capacity.

DSM Application for Deep Excavation in Singapore (싱가포르 지역 깊은 굴착을 위한 지반개량공법 DSM의 적용 사례)

  • Chun, Youn-Chul
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.12 no.5
    • /
    • pp.2425-2433
    • /
    • 2011
  • DSM (Deep Soil Mixing) is to establish soil-cement column by injecting of cement slurry and blending it in soft ground and have been introduced to Singapore in 1980s and now a days quite popular and considered as alternative method to the jet grouting for temporary earth retaining works and foundations. Herein this paper, the results of lab mixing test based on comparison of characteristics between OPC (Original Portland Cement) and PBFC (Portland Blast Furnace Slag Cement), DSM field trial test and main installation results including monitoring, was presented and it would be referred to similar site later.

Square Jet Grouting to Reduce Permeability (사각(四角)제트 그라우팅 공법에 의한 지반차수 특성)

  • Gwak, Soo-Jeong;Baek, Hong-Ryul
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2005.10a
    • /
    • pp.188-197
    • /
    • 2005
  • Square patterned jet grouting technique is the soil improvement method that shakes the special end monitor left and right like as tail fin and mixing the soil and cement paste after cutting the soil in square shape by injecting the cement paste from installed two nozzles. The structure shape by jet grouting technique can be constructed in various shapes and sizes like as square, circle, and sector form designed by an engineer. Also, it can be constructed without waste material and reduced a construction time of work economically. In this study, the applicability of Square Jet Grouting to reduce permeability is estimated by FEM analysis and in-situ test in many cases which are various coefficient of permeability and breadth of grouting structure.

  • PDF