• 한국지반환경공학회 논문집
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• 제24권4호
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• pp.13-22
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• 2023

본 논문에서는 시험적 연구를 통해 록볼트가 지보효과를 발휘하는 시기를 그라우트 강도로 제시하고, 수치해석적 연구를 통해 지반조건과 경계면 강도감소계수에 따른 록볼트 인발 거동을 분석한 연구를 다루었다. 그 결과 록볼트는 그라우트 강도 5 MPa(재령 18시간)에서 지보효과를 발휘하였으며, 경계면 강도감소계수의 영향은 록볼트 변위의 경우 연약한 지반일수록, 그라우트- 지반의 전단응력의 경우 지반의 탄성계수가 높을수록, 그라우트 응력의 경우 모든 지반조건에서 영향이 큰 것으로 분석되었다. 이러한 연구결과는 록볼트 인발시험의 구체적인 기준 재정립과 록볼트 수치해석에 도움이 될 것으로 판단된다.

• 한국구조물진단유지관리공학회 논문집
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• 제27권3호
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• pp.47-57
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• 2023

본 연구에서는 스터럽 간격, 철근 직경 및 부식률이 이형철근의 부착강도에 미치는 영향을 파악하고자 인발실험이 수행되었다. 스터럽 간격, 철근 직경 및 부식률이 상이한 12개의 인발 실험체를 RILEM RC 6 기준에 따라 제작하였다. 스터럽이 보강된 실험체에 대하여, 부식률이 3% 미만인 경우에는 부착강도가 증가하였으나, 부식률이 3%를 초과한 경우에는 부착강도가 감소하였다. 반면, 스터럽이 보강되지 않은 실험체에 대해서는, 부식률이 증가함에 따라 부착강도가 감소하였다. 스터럽 간격 및 부식률 대비, 철근 직경이 부착강도에 미치는 영향은 적은 것으로 나타났다. 이에 따라 스터럽 비율 및 부식률을 변수로 사용하는 인발실험체의 부착강도 회귀모형이 제시되었으며, 제안모델은 선행 모델들에 비해 낮은 오차를 나타내었다.

• 한국농공학회논문집
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• 제63권3호
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• pp.27-33
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• 2021

Reclaimed land was mainly used as agricultural land for rice production. As a higher value-added business in the agriculture has recently been activated, green houses are being constructed. In case of green house construction on the reclaimed land, it is generally soft ground with high soil water content, so it is important to design the foundation for greenhouse construction. The object of this study, a pull-out test was conducted to derive the base line data of the wooden pile foundation when constructing a green house. To reproduce the actual site, 30% of soil saturation and 70% of soil saturation were created in the soil box. Groove number and depth were set as design factors of the wooden pile, and a pull-out test was conducted. As a result of the test, pull resistance increased as the number of grooves increased, pull-out resistance according to groove depth was different according to soil saturation. Also, after the experiment, we want to compare the set-up effects over time.

• 한국안전학회지
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• 제17권2호
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• pp.85-91
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• 2002

A research on the performance of retrofit anchors was conducted using adhesives for rehabilitation. From the pull-out tests of the chemical anchors, the effect of the hole diameter, spacer, temperature, moisture, embedment depth, and aging time were investigated. The spacer did not directly increased the pull-out load hilt increased post-yielding resistance therefore the ductility of the retrofit anchors. When the hole was cleaned and dried after the immersion, the pull-out load was greatly increased compared to the wet hole. A design equation was unposed depending on the embedment depth of the anchor bolt.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.405-411
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• 2008

The pressurized grouting soil nailing method using rubber membrane packer system was developed for recycling materials to minimize environmental pollution and reducing construction costs. For this purpose, field pull-out tests were performed to evaluate the characteristics of soil nailing by measuring tensile stresses and axial displacements.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.127-134
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• 2000

Soil nailing is in-situ ground improvement technique of reinforcing soils using passive inclusions for the purpose of slope stability. Also soil nailing, in general, was used and studied as a reinforcement technique at cut slope, but this paper presents the results of study for soil nailing application as a reinforcement technique at the banking over slided slope. In-situ pull-out tests of nails, instrumented with strain gauges, were performed to investigate the maximum pull-out load and to calculate the unit side resistance in each different layer. And the apparent average unit side resistance of this study was compared with that of other sites installed at cut slope.

• 한국기계가공학회지
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• 제16권1호
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• pp.102-111
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• 2017

An automobile ball joint is the element for connecting the control arm and the knuckle arm, allowing rotational motion. The ball joint consists of the stud, plug, socket, and seat. These components are assembled through the caulking process that consists of plugging and spinning. In the existing research, the pull-out strength and gap stiffness were calculated, but we did not consider the uncertainties due to the numerical analysis and production. In this study, the uncertainties of material property and tolerance are considered to predict the distributions of pull-out strength and gap stiffness. Also, pull-out strength and gap stiffness are predicted as the a distribution rather than one deterministic value. Furthermore, a robust design applying the Taguchi method is suggested.

• 한국공간구조학회논문집
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• 제15권4호
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• pp.65-72
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• 2015

To overcome the weakness of spread foundation in large space structure, the research of precast pile for replace spread foundation have been conducted. The new type of joint between PHC pile and steel column is named HAT Joint(Hollow hAlf-sphere cast-sTeel Joint). It connected PHC Pile by bolt that verification of bolt connection should be accomplished. In this paper, pull-out test and flexural performance for HAT Joint to verifying the bolt connection is explained. As a result, the pull-out and flexural capacities of bolt were checked to use in real structure. Furthermore, the equation of pull-out strength was proposed.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회 2차
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• pp.88-95
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• 2010

Screw piles(Helical piles and anchors) are increasingly used to support and rehabilitate reinforced structures subjected to both tensile and compressive axial loads. This study presents a variety of detailed investigation on especially pull-out characteristics of screw piles performed to both reduced scale and numerical analysis to identify fundamental failure mechanisms and empirical optimized geometry of screw piles. It was found that the pull-out characteristics of screw piles are influenced with mainly different frequencies of compaction around soil and screw pile's pitch and followings are practical data based on empirical analysis.

• 한국구조물진단유지관리공학회 논문집
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• 제2권3호
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• pp.188-193
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• 1998

An experimental study was performed on the pull-out behavior of 90-deg standard hooks from exterior beam-column connections. The effects of lateral confinement and fiber reinforcement of joint area were investigated. It was concluded ; (1) Substitution of the transverse column (confining) reinforcement with steel fibers at the joint region effectively reduces the extent of cracking in exterior joints caused by pull-out of hooked bars; and (2) The strength and ductility of hooked bars under pull-out forces are positively influenced by substituting the conventional confining reinforcement of exterior joints with steel fibers. Application of steel fibers to exterior joints seems to be an effective technique for improving the anchorage conditions of hooked bars, and also for reducing the congestion of reinforcement in exterior beam-column connections.