• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.6C
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• pp.295-301
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• 2009

In general the stability of soil nail-slope system, the shear resistance is neglected because the tensile resistance of nail acts mainly for slope stabilization. This is because that deformed steel is generally used for nail and it does ductile behavior. In other side when the steel pipe with high rigidity is used for nail, the shear resistance at failure surface work more than deformed steel. In order to analyze effects of shear resistance at the soil nail-slope system with high steel piped nail, a series of numerical analyses were performed. Also numerical analyses at 3 conditions - 5 nailed, 7 nailed, 9 nailed at the same slope were perfomed for investigating the trend of shear resistance effect. From these 3D numerical analyses, it was found that the maximum shear resistances at each nails were larger in case of steel piped nail and because of this, the factor of safety at the condition of the steel piped nail appears larger than that of deformed steel nail.

• Journal of the Korean Society of Safety
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• v.22 no.1 s.79
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• pp.54-60
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• 2007

This paper describes typical design and construction practice for in-situ ground reinforcement technique using improved steel pipe pressure grouting. A case history is presented to illustrate the benefit gained by application of the technique. This technique was applied to cut slopes developed in the construction of auxiliary spillway of 00 dam. Applicable conditions, method of survey, slope stability analysis and construction are given in this parer. As for the construction method, a procedure is given and the main points are the control of construction work. As a result of the pull-out test, it is shown that seel pipe nailing is particularly useful for stabilizing rock slope.

• Journal of the Korean Geosynthetics Society
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• v.8 no.4
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• pp.19-25
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• 2009

In this study, field pull-out tests were performed for steel pipe nailing installed foldable wedge and non-wedge type steel pipe nailing under the same test conditions. This is to evaluate pull-out resistance improvement effect of steel pipe nailing installed foldable wedge. Evaluating for field pull-out characteristics of steel pipe nailing installed foldable wedge was performed through analysis of ultimate pull-out resistance ($T_L$), ultimate unit skin friction ($q_s$, $u_{max}$), tensile normal stiffness ($K_{\beta}$), tension of nail. As a result, the steel pipe nailing installed foldable wedge have an effect of pull-out resistance increased about 30% in comparison with non-wedge type steel pipe nailing.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.6C
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• pp.313-319
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• 2009

In this study, field pull-out test and 3-D FEM analysis have been performed for examining and reflecting the behavior of steel pipe nailing installed foldable wedge. Field pull-out test was performed under various conditions. As a result, the steel pipe nailing installed foldable wedge has an effect of pull-out resistance increased about 30% in comparison with non-wedge type steel pipe nailing. Through back analysis in 3-D FEM for behavior of non-wedge type steel pipe nailing, friction characteristics between nail to soil was analyzed and obtained first consistent with field pull-out behavior. Then, the frictional characteristic was used for analyzing the behavior of the steel pipe nailing installed foldable wedge. The result was compared with the test results. Consequently, friction coefficient (${\mu}$) of about 1.2 between grout to soil leads to good agreement with analysis results and test results. And a limited pull-out resistance, $$T_L{\sim_=}32$$ tonf is similar to field pull-out test result which is improved about 33% in comparison with non-wedge type steel pipe nailing's $$T_L{\sim_=}24$$ tonf.

• Journal of the Korean GEO-environmental Society
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• v.22 no.2
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• pp.5-13
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• 2021

In this study, as the production of high-strength steel pipes due to the development of steel materials, the stability and applicability of the soil nailing method using high-strength steel pipes were evaluated. Rebars used as reinforcement in the soil nailing method are the same in order to determine the behavioral characteristics and the effect of increasing the reinforcement when replacing it with a high-strength steel pipe of a diameter, a field test were conducted to confirm the stability. As a result of the tensile test, the measured strain is smaller than the strain in the theoretical equation, so it can be seen that the behavior is similar to that of the soil nailing method using rebars. As a result of the displacement measurement, the displacement of the high-strength steel pipe is larger than that of the rebars is considered to be the effect of the internal grouting effect of the steel pipe and the decrease in the cross-sectional area. In the case of using high-strength steel pipes for the soil nailing method, it is judged that the field applicability is good by improving stability and workability through member performance and weight reduction.