• Proceedings of the Korean Geotechical Society Conference
• /
• 1999.10a
• /
• pp.481-488
• /
• 1999

Recently a removable soil nail is demanded due to problems beyond of economical and engineering purpose. In this study controlled displacement and controlled force field pull-out tests are carried out 7 times in order to evaluate short-term and long-term pull-out characteristics of the removable soil nail. For evaluating application of removable soil nailing system, bending tests of removable soil nails and tensile tests of fixed sockets are carried out. In the removable soil nailing system, the predicted horizontal displacements from FLAC-2D are also compared with the field measurements occurred in stepwise excavation. And approach for the stability analysis of removable soil nailing system after removed is proposed.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2010.03a
• /
• pp.240-247
• /
• 2010

The soil nailing system is becoming common as reinforcement method of slope face in soil. It has application to obtain slope stability method and scaffolding system. It has some troubles when the soil nailing system is applied to the downtown because it could be invaded someone's private area. Thus, in this paper, wedge type removable soil nailing system which can easily remove deformed bar in final excavation step is developed. Field pull-out test is performed to evaluate deformed bars removal and pullout resistance characteristics. According to this result, application of Wedge Type Removable Soil Nailing System is performed.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2009.09a
• /
• pp.1360-1364
• /
• 2009

Necessity of removable soil nailing has been arisen in the soil nailing system because of problem such as civil petition for geotechnical environment and invasion of the ground boundary line and payments for use besides geotechnical engineering. Removable soil nailing system is improved soil nailing system that fixed socket arranged in boring hole for increasement of skin friction. In this study, field pull-out tests are carried out more 4 times considering installed distance of fixed socket and analyze skin friction behavior characteristics in fixed socket through analysis of measurements of strain gauge attached to fixed socket. Also, to evaluate application for wedge type removable soil nailing system analyzing displacement aspects through field pull-out tests by trial construction.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2010.09a
• /
• pp.1081-1086
• /
• 2010

The general soil nailing support system may result in excessive deformations particularly in an excavation zone of the existing weak subsoils. Pretensioning the soil nails then, could play important roles to reduce deformations mainly in part of the nailed-soil excavation system as well as to improve local stability. Morever, soil nails are installed underneath roads, underground structures, and subway structures, thereby resulting in difficulties in nail remval after completion of temporary soil nailed walls. Hence, to date, in order to solve the technical difficulties and avoid legal issues related to the construction of soil nails underneath the surrounding areas and structures, the removable soil nailing system has been developed and used. But, Therefore, a new soil nailing technique called Removable Post-tensioned Soil Nailing(RPTN) system has been developed in the current study. In this study, an investigation of the RPTN system has been conducted by carrying out field measurement. Hence, the RPTN system can reduce ground displacement and enhance stability of the soil nailed walls.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2006.03a
• /
• pp.1014-1023
• /
• 2006

Soil nailing is a reinforcement method used for stabilizing excavated wall or slope. Due to its many advantages such as ease of construction and economical efficiency, use of soil nailing is increased. However, the soil nail can't trespass on the neighbor private land, which pays rent for use. For this reason, removable soil nailing system was developed. However, the removal rate of this system is just about $50\sim70%$. To solve this, the Fiber Reinforced Polymer (FRP) soil nailing system, which does not need to be removed and allows for the trespass on the private land, is developed. In this paper, through theoretical and experimental studies in laboratory and field, we evaluate the stability and behavior characteristics of the FRP nail system. Besides, numerical analyses using FLAC2D were performed for various soil conditions, where the simulations for pullout tests were carried out. As a result, compared with the conventional removable soil nailing system, the FRP soil nailing systems show similar behavior characteristics.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2009.09a
• /
• pp.1330-1333
• /
• 2009

The soil nailing method had used in variable construction field because of construction convenience and reinforcement effect. Especially, the removal soil nailing method is useful support system in vertical excavation. In this study, to develop the wedge type removable soil nailing method for improvement of the removal soil nailing method. Because of the reinforcement materials is most important in soil nailing method, to evaluate the mechanical characteristics during laboratory strength test in this study. To conduct bond strength test of deformed bar combined with a wedged screw inside plastic fixed socket for evaluate the strength characteristics of wedge type removable soil nailing method and evaluate the strength characteristics of fixed socket based on laboratory tests.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.26 no.6C
• /
• pp.385-393
• /
• 2006

Soil nailing is a reinforcement method used for stabilizing excavated walls or slopes. Due to its much advantages such as ease of construction and economical efficiency, use of soil nailing is increased. However, the soil nail has much disadvantages for use in urban area. The soil nail needs to be installed inevitably beyond private land boundary, which causes rent for use. For this reason, removable soil nailing system was developed. However, the removal rate of this system is just about 50￠¦70%. To resolve this problem, the Fiber Reinforced Plastic (FRP) soil nailing system which does not need to be removed and allows for the installation beyond private land, is developed. In this paper, through theoretical and experimental studies in laboratory and field such as prototype tests, pullout tests, we evaluate the stability and behavior characteristics of the FRP soil nailing system. And, numerical analyses using FLAC2D were performed with respect to various soil conditions, where prototype test for excavation wall and pullout tests were carried out. As a result of this study, the FRP soil nailing systems show similar behavior characteristics with those of removable soil nailing system. Finally, considering the serviceability and mechanical stability of FRP soil nailing systems, it is enough to be used as a good alternative of general soil nailing system.

• Journal of the Korean GEO-environmental Society
• /
• v.10 no.7
• /
• pp.151-158
• /
• 2009

In the early 1990s, soil nailing was first introduced as method of reinforcement for the slope stability and ground excavation, and as its application was increased the improved soil nailing was also developed. Most recently used for grout soil nailing greatly improve the methods and techniques for self-improvement techniques are classified as soil nailing. As the representative for the grout pressure method to improve the join method pressure grouting and improved method for the self-drilled soil nailing, removable soil nailing, upward soil nailing combined with horizontal drainage system. This paper is to compare upward soil nailing combined with horizontal drainage system with downward direction of the soil nailing. In order to study the limit equilibrium slope stability analysis and comparison with factor of safage, excavation for the vertical displacement for comparison with continuous analysis. According to this study, safage factor is decreased considerably using limit equilibrium analysis and makes no odds for the horizontal displacement when soil nail was installed upward.

• Journal of the Korean Geotechnical Society
• /
• v.16 no.3
• /
• pp.107-117
• /
• 2000

쏘일네일 벽체는 국낸에서 과거 10년간 가시설 및 영구구조물에 상당수 시공되어 왔다. 그러나 쏘일네일링 공법은 많은 장점이 있음에도 불구하고 인접한 건물의 하부에 쏘일네일이 삽입되는 것을 허용하지 않아 제한적으로 사용되고 있는 실정이다. 따라서 본 논문에서는 쏘일네일이 인접한 건물의 하부에 삽입되는 문제를 해결하고 철근을 재활용할 수 있는 방안으로 제거식 쏘일네일링 공법을 소개하였다. 제서식 쏘일네일링 공법은 연직굴착시 가시설 흙막이벽체로 주로 사용할 수 있다. 제거식 쏘일네일의 인발특성을 규명하기 위해 총 23회의 현장인발실험을 실시하였으며, 이를 통해 고정자 소켓의 설치간격과 시멘트 그라우트의 W/C 비가 중요한 설계인자라는 것을 알 수 있었다. 또한 본 논문에서는 국내에서 처음으로 시공되는 제거식 쏘일네일 벽체의 설계 및 시공과 시공상태 등을 소개하였으며, 제거식 쏘일네일의 철근을 제거하기 전과 후에 벽체의 변형을 계측자료로부터 분석하였다.