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현장 계측을 통한 블록형 보강토옹벽 곡선부 보강 영역의 거동 특성 연구

A Study on Behavior Characteristics of Reinforcement Zone of Block Type Mechanically Stabilized E arth Wall by Field Measurement in Curved Section

  • Lee, So-Yeon (Department of Railroad Construction and Safety Engineering, Dongyang Univ.) ;
  • Kim, Young-Je (Department of Railroad Construction and Safety Engineering, Dongyang Univ.) ;
  • Oh, Dong-Wook (Department of Civil Engineering, Seoul National Univ. of Science and Technology) ;
  • Lee, Yong-Joo (Department of Railroad Construction and Safety Engineering, Dongyang Univ.) ;
  • Jung, Hyuk-Sang (Department of Railroad Construction and Safety Engineering, Dongyang Univ.)
  • 투고 : 2018.11.20
  • 심사 : 2019.06.17
  • 발행 : 2019.06.30

초록

본 논문에서는 블록식 보강토옹벽의 현장계측을 통해 곡선부 보강영역의 변형특성을 분석하였다. 보강토공법은 설계 및 시공이 증가하여 실생활에서 쉽게 접할 수 있게 되었으나, 곡선부의 균열 및 붕괴사례가 빈번히 발생하여 안전에 대한 중요성이 대두되고 있다. 이러한 붕괴원인은 곡선부에 대한 연구 부족과 설계기준의 미흡, 경제성과 공기단축에 의한 시공성 결여, 충분하지 못한 다짐 공간 등에 있다고 할 수 있다. 이에 본 연구에서는 기존 설계 및 시공 기준을 검토하고 블록형 보강토옹벽 곡선부 사고사례를 통해 원인을 분석하였으며, 실제 시공된 블록형 보강토옹벽의 현장계측을 통해 직선부와 곡선부의 거동을 비교 분석하고 곡선부 보강영역의 변형특성을 확인하였다. 그 결과, 먼저 곡선부의 수평변위가 직선부와 비교하여 볼록형에서 최대 90%, 오목형에서 최대 60% 높게 나타났으며, 다음으로 곡선부 보강영역에서 볼록형의 경우 보강토옹벽 중심에서 수평방향으로 H/2구간에서 최대변위를 보이며 H까지의 영향범위를 나타내었으며, 오목형의 경우 중심에서 최대변위를 보이며 수평방향으로 H/4구간에서 최소변위를 확인하였다. 이러한 결과로 형태에 따른 곡선부의 영향범위와 현장적용을 위한 보강영역의 재정립이 필요하다고 판단되며, 본 연구결과가 이를 위한 기초 자료로서 활용 가능할 것으로 판단된다.

In this paper, field measurement of the Block Type Mechanically Stabilized Earth (MSE) wall curved section was performed, and the reinforced area of the curved part is studied through the result. MSE method has been applied to various fields because of easy construction and excellent economic efficiency, so that it can be easily access in our life. However due to lack of compaction and stress concentration phenomenon, cracks and collapse occur in the curve of MSE wall, which is important for safety. The cause of collapse is lack of research on curved section, lack of design criteria, lack of construction due to economical efficiency and shortening of construction period, insufficient compaction space. In this study, therefore, it was examined the existing design and construction standards, analyzed the cause through accident examples of the curved section of the Block Type MSE wall. As a result, the horizontal displacement of the curved section was 90% higher than that of the straight section and 60% higher than that of the concave section. In the case of the convex section in the curved section reinforcement region, the maximum displacement is shown in the H/2 section in the horizontal direction from the center of the MSE wall, and the range of influence from H is shown. In the case of the concave section, the maximum displacement is shown in the center, The minimum displacement was confirmed in H/4 section in the horizontal direction from the center of the MSE wall. As a basic study on the reinforcement area rehabilitation through the actual construction of block type MSE wall, the behaviors of the straight part and the curved part were compared and analyzed. And analyzed the reinforced area in order to reduce the damage of the stress concentration phenomenon and secure the safety.

키워드

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Fig. 1. Installed stiffener at curve section of mechanically stabilized earth wall in domestic (Ministry of Land, 2016)

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Fig. 2. Installed stiffener at curve section of mechanically stabilized earth wall in foreign country (NCMA, 2016)

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Fig. 3. Collapse case at curve section of Block type mechanically stabilized earth wall

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Fig. 4. Scene of Block type mechanically stabilized earth wall

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Fig. 5. Field measurement

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Fig. 6. Kriging of Block type mechanically stabilized earth wall

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Fig. 7. Displacement according to Plane Reinforcement area

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Fig. 8. Re-installation of reinforced earth walls reinforcement area

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Fig. 9. Horizontal Displacement

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Fig. 10. Bulging according to shape

Table 1. Displacement of convex section

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Table 2. Displacement of concave section

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