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

• Journal of the Korean GEO-environmental Society
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• v.14 no.3
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• pp.19-27
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• 2013

Recently, the natural and man-made slope collapses occur frequently because of sudden heavy rains. So, a variety of slope reinforcement methods have been developed and applied to failure slopes. Soil nailing method usage has been increased because of its workability and economic aspects. This method has been applied in combination with other slope stability methods. Soil nailing method is a kind of combinational structure of steel bar and cement grouting. This method uses skin friction between adjacent ground and cement grouting to stabilize the slope. In this study, End-expanded soil nailing method was developed. This method consists of steel bar and anchor body attached at the tip of the nail. During construction, the anchor body at steel bar tip is settled to the ground through the expanding action. In this study, field pull-out tests were performed for un-grouting soil nailing and grouting soil nailing. From the test results, a wedge force of End-expanded soil nailing method was analyzed. And the behavior characteristics of End-expanded soil nailing were studied.

• Journal of the Korea Construction Safety Engineering Association
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• s.47
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• pp.56-62
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• 2008

In order to apply the Limit Equilibrium Method generally used for the slope stability analysis to the vertical excavation walls reinforced by soil-nailing, in this study, the Limit Equilibrium Method for the temporary shoring facilities reinforced by soil-nailing was proposed, which is based on the stability for the horizontal displacement. In this study, the relation of the internal friction angles of the ground and the vertical excavation depths was arranged, which is satisfying the stability on the horizontal displacement by using the verification of the Limit Equilibrium Method. And then, the rational reinforcing length of soil-nailing was proposed for the critical areas. In addition, the modified safety ratio satisfying the stability on the horizontal displacement was proposed, when the Limit Equilibrium Method was applied to the vertical excavation walls reinforced by soil-nailing.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.113-120
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• 2005

Soil nailing system can be mentioned to a method of supporting as the shear strength of in-situ soils is increased by passive inclusions. In the general soil nailing system, facing walls are used in two kind of a lattice concrete block or a cast in placed concrete wall. A case of lattice concrete blocks is used in slow slopes greater than 1:0.7. Also, a case of a cast in placed concrete wall is used in steep slopes less than 1:0.5. The cast in placed concrete walls are constructed to 30cm thick together with a shotcrete facing. In this study, the assembling soil nailing method as a new soil nailing system is proposed. This method is constructed assembly using precast concrete panels. Therefore ability of the construction and quality of the facings can be modified than a usual soil nailing system. Also, this method can be obtained the effects that a global slope stability increase, as precast concrete panels is put on cutting face after excavating a slope.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.1086-1091
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• 2009

The purpose of this study is to provide the technical information of the stability change and behaviour characteristics in case upward direction of soil nailing is installed. Generally, the soil nailing which installed in case of vertical excavation or for the purpose of the slope stability is installed between 5 to 15 degree of downward direction. The downward direction of the soil nailing method has lots of advantages such as the increase of the stability, the convenience of the grout compared to upward direction of soil nailing. Even though the upward direction of the soil nailing has the disadvantages in terms of the stability and the grout construction, horizontal displacement tends to be decreased.

• Journal of the Korean GEO-environmental Society
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• v.11 no.3
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• pp.53-62
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• 2010

In the early 1990s, it was first introduced the soil nailing method for the slope stability and ground excavation and widely used as method of reinforcement. Also the application of soil nailing has been improved and 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, extension grout method. Three dimensional finite difference analysis was used to evaluate characteristics of pull-out behavior of extension grout method. In this paper, it was described a characteristics of pull-out behavior of soil nailing with extension grout method through the result of numerical method.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.10
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• pp.2794-2802
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• 2009

Soil nailing method is widely used in reinforcing slopes and excavating earth. The analysis of nail-reinforced slopes, generally require complicated computer programs. The purpose of this paper is suggest, Soil stability Chart for nailed slopes which are very useful for pre-design, rapidly design, and final check. Three slope types, three nail lengths and three nail angles are selected for the stability analysis by using limit equilibrium method form Bishop and French. From the above results, this study propose the reinforced design charts for examine the necessity of reinforcement can be examined. The suggested stability chart and Taylor's Slope Stability Chart, showed similar safety factors. This Soil Nailing design charts can provide the solutions for necessity of reinforcement, economical of nail's length ratio and installation angle as well.

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

• Journal of the Korean Geotechnical Society
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• v.29 no.8
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• pp.27-36
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• 2013

LEM (Limit Equilibrium Method) based programs are commonly used for the designs of soil nailing as a slope reinforcement. However, there is a drawback that the interaction between ground and soil nailing is not properly reflected in those programs, which needs to be solved. For economical constructions and designs, research is also required on the support pattern of soil nailing. In this study, therefore, reinforcement effects of soil nailing were compared and analyzed by performing finite difference analyses which could properly consider the interaction between ground and soil nailing. As a result, when the angle from slope to nail is $90^{\circ}$, failure slip surface becomes the largest and thus the factor of safety becomes maximum.

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