• Journal of the Korean Society of Hazard Mitigation
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• v.6 no.4 s.23
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• pp.7-14
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• 2006

The tilting-train being operated in pre-existing rail road has a different running mechanism compared to currently operated trains. Therefore, it needs to investigate the evaluation of the track performance, the stability of the tilting-train in operating condition, and the stability of the roadbed. In this study, when the tilting train is operated in the rail joint with the allowable velocity limited by the track performance and the stability of the tilting-train, the settlement of the roadbed has been evaluated by using numerical analysis. The loading on the ground surface generated by the operating tilting-train generates the settlement of the roadbed. The settlement induced by the tilting-train loading has been compared to the allowable settlement and the factor of safety defined by the ratio of the allowable settlement to the settlement generated by the applied loading is evaluated.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.1 s.24
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• pp.29-38
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• 2007

The research on the track performance and stability of the tilting-train was performed and the settlement of the roadbed was estimated as the tilting train was being operated on the rail joint under the allowable velocity subjected to the track performance and the stability of the tilting-train. Since the impact on the continuous welded rail (CWR) induced by the tilting-train loading is different from the impact on the rail joint, it needs to investigate the settlement of the roadbed beneath the CWR. In this study, when the tilting-train is being operated on the CWR under the allowable velocity subjected to the track performance and the stability of the tilting-train, the settlement and bearing capacity of the roadbed beneath the CWR have been evaluated using numerical analysis and compared with those beneath the rail joint. The numerical results show that the settlements of the roadbed beneath CWR and rail joint are amount to 71.2% and 88.8% of the allowable settlement, respectively. And the stresses are amount to 10.4% and 12.1% of the allowable bearing capacity, respectively.

• Journal of the Korean Geosynthetics Society
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• v.8 no.4
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• pp.9-17
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• 2009

This research was intended to verify the stability of landfill final cover using SRSL(Self Recovering Sustainable Liner) with regard to differential settlements due to the degradation of waste and so on in a waste landfill. Numerical analysis was performed using FLAC 2D software program with input parameters based on soil characteristic tests and reference data after the blank was designed in order to represent the decomposition condition of waste. The maximum settlement of landfill cover was calculated to investigate the structural stability of landfill cover with the different condition of settlement width, settlement depth, and number of differential settlements. The allowable maximum deformation rate of SRSL, which was calculated using field permeability tests, was 6 mm. The analysis showed that SRSL was stable in case of a differential settlement width not exceeding 24.5% of total cover width.

• International Journal of Highway Engineering
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• v.8 no.1 s.27
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• pp.77-87
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• 2006

Dynamic stability (DS) in the wheel tracking (WT) test is used as a basic index of rut-resistance for asphalt mixtures. In general, the deeper rut depth is obtained from the weaker mixture, resulting in the lower DS value. On the other hand, the shallower rut depth is obtained from the stronger mixture, resulting in the higher DS. However, it is not always the case when the DS is calculated by the existing method because the DS is simply determined based on the slope at the final stage of the rut depth-cycle curve. Specifically, in the case of the depth-cycle curve showing a steeper slope in the early part but flatter slope in last part, the DS is calculated to be higher than the curve showing a ever-increasing slope throughout the test. As long as the last part of slope is flatter, the deeper final rut depth is evaluated to show a higher DS than the little final rut depth. Therefore, a reasonable method for DS evaluation need to be established. Several new methods were suggested by considering the early, middle and final parts of rut depth to determine a reasonable DS. The results have shown that those new methods have demonstrated a significant improvement in distinguishing similarly performing mixtures. The result also showed that $DS_2$ had better correlation with SD than any other methods , representing the rutting resistance of asphalt mixture very well. The new DS calculation method is relatively simple and easy to follow. More validatin study is required for practical application.

• Journal of the Korean Geosynthetics Society
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• v.13 no.4
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• pp.87-96
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• 2014

In this paper, reliability analysis was done on the characteristics of consolidation and settlement for the inner temporary dike where a weak ground improvement construction was applied. When the consolidation analysis on the foundation ground was done, the following conclusions were obtained by conducting the stability analysis on the effect of space of drains, the effect of consolidation time, and the residual settlement and differential settlement. When construction was done with a drain space which satisfied 95% probability of reaching a target consolidation in each divided area, the occurrence of a residual settlement was within the range, which did not exceed 10cm. It was shown that there was almost no possibility of the occurrence of differential settlement, which was above the permissible differential settlement slope.

• Journal of the Korean GEO-environmental Society
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• v.7 no.6
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• pp.23-34
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• 2006

In this study, the centrifugal tests were performed to evaluate the behavior of reinforced retaining wall that allows the settlement of reinforcement strip. To analyze the stability of reinforced retaining wall, which drives the settlement of reinforcement strip, the results were compared with the conventional reinforced retaining wall. In the centrifugal tests, the aluminum plate for the face was used and the aluminum foil was used as a reinforcement. The decomposed granite soil was adopted as a backfill. As a result, the settlement free reinforced retaining wall reached to the failure at 80g-level. In contrast, the conventional reinforced retaining wall was collapsed at 69g-level. It means that the settlement free reinforced retaining wall has the stronger stability than the conventional reinforced retaining wall. Also, vertical earth pressure of the settlement free reinforced retaining wall near the base of wall was higher 16% than that of the conventional reinforced retaining wall.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2017.11a
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• pp.195-196
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• 2017

연약한 지반 위에 시공되는 보강토 옹벽이 연약지반의 침하에 대하여 안정성을 분석하고 지반의 처리를 어떻게 하는 것이 향후 재난발생을 예방할 수 있는지에 대하여 침하량을 분석하고 대처 방법에 대하여 분석하였다.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.667-667
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• 2012

호안블록을 설치하는 목적은 제방의 비탈면 및 저수로 하안을 강수나 유수에 의한 침식작용으로부터 보호하는데 있다. 근래에 들어서는 친수성, 경관, 생태계 보전 및 재생 등과 같은 기능을 가진 다양한 호안블록의 시공이 이루어지고 있는데 이러한 국내 상황은 호안블록에 관한 수리적 연구와 안정성 검토의 필요성을 증가시키고 있다. 현재 국내에서는 호안의 설계 및 시공시에는 하천공사 표준시방서 등을 이용하고 호안블록 제작에는 콘크리트 표준 시방서 등을 이용하고 있다. 그리고 이런 시방서의 내용들은 호안블록 설치 후 호안의 안정성을 보장하는 듯 하다. 하지만 이는 모두 호안블록의 재료 및 설치 기준에 관한 지침서일 뿐이며, 어느것도 호안블록 설치 이후에 호안의 안정성을 보장하지는 않는다. 따라서 현재 국내 상황을 고려한 호안블록 주변의 수리특성에 관한 연구와 안정성 평가 기법의 개발은 매우 시급한 과제이다. 본 연구에서는 한국건설기술연구원 안동 하천실험센터 실규모 수로에 최근 미국과 일본에서 적용하고 있는 호안블록의 안정성 평가 지침을 참고하여 호안블록 시험구간을 설치한 뒤, 서로 다른 형태의 호안블록 두 종류에 대하여 실험을 수행하였다. 실험에 사용된 호안블록은 실재 현장에서 사용되는 블록과 동일한 제품을 사용하였다. 실험 결과 두 종류의 호안블록에서 모두 기반 토층의 침하 현상이 발견되었으며, 그 중에서 블록 중앙에 구멍이 있는 형태의 호안블록의 경우에는 구멍 내부에서 발생한 강한 세굴 현상이 침하로 이어져 결국에는 호안블록이 설치된 구간 전체가 파손되는 양상을 보였다. 또한 유속이 빠른 구간에서 블록의 파손이 더 심화되는 양상도 확인하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.317-324
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• 2020

In this study, a simplified equation for settlement evaluation suitable for the special conditions of a counter facility is suggested. Recently, counter facilities, especially breakwaters, are constructed on soft ground in distant seas as new-port development projects. A counter facility that resists the external forces by self-weight settles easily when constructed on soft ground. Settlement in a counter facility and breakwater is not an important factor for maintenance than a land facility. On the other hand, the current settlement evaluation criteria are excessive for conducting a safety inspection. A settlement evaluation from a safety inspection followed by "Detailed Guidelines for a safety inspection on a counter facility" is used. A simplified equation was proposed to calculate the maximum settlement by applying the allowable residual settlement or settlement stability evaluation results. The suitability of the simplified equation was assessed compared to the assessed rating from the settlement survey results. The proposed simplified equation showed that the settlement evaluation rating had been upgraded. The proposed simplified equation is expected to be used to evaluate the practical structural stability and functional performance.

• The Journal of Engineering Geology
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• v.15 no.4 s.42
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• pp.423-433
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• 2005

For the design of spread foundation and the stability evaluation, we compared and analyzed it for theoretical, empirical bearing capacity formulas, and various settlement computation formulas, by conducting the plate bearing test at the site of A and B, which consisted of gneiss weathered soil. In addition, we considered the effective method of stability evaluation by carrying out the plate bearing test carried out on the ground consisted of weathering soil of gneiss. Consequently, it was found out that the allowablebearing capacity by the theoretical formula of Terzaghi was too excessive in comparison with the result of the plate bearing test and the Terzaghi-Peck method, which was used widely domestically in designing the spread foundation. It was more effective for a stable design. As a result of the plate bearing test carried out, on the ground consisted of weathering soil. It was found that reviewing the stability by the bearing capacity calculated with load-settlement curve. It is evaluated in a safer side than the point of view of the settlement.